Last Updated on December 13, 2021 by Admin 3

CISA : Certified Information Systems Auditor : Part 68

  1. Which of the following statement INCORRECTLY describes Asynchronous Transfer Mode (ATM) technique?

    • ATM uses cell switching method
    • ATM is high speed network technology used for LAN, MAN and WAN
    • ATM works at session layer of an OSI model
    • Data are segmented into fixed size cell of 53 bytes

    Explanation:

    The keyword INCORRECTLY is used within the question. You need to find out a statement which was incorrectly describe Asynchronous Transfer Mode.ATM operates at data link layer of an OSI model

    For your exam you should know below information about WAN Technologies:

    Point-to-point protocol
    PPP (Point-to-Point Protocol) is a protocol for communication between two computers using a serial interface, typically a personal computer connected by phone line to a server. For example, your Internet server provider may provide you with a PPP connection so that the provider’s server can respond to your requests, pass them on to the Internet, and forward your requested Internet responses back to you. PPP uses the Internet protocol (IP) (and is designed to handle others). It is sometimes considered a member of the TCP/IP suite of protocols. Relative to the Open Systems Interconnection (OSI) reference model, PPP provides layer 2 (data-link layer) service. Essentially, it packages your computer’s TCP/IP packets and forwards them to the server where they can actually be put on the Internet.

    PPP is a full-duplex protocol that can be used on various physical media, including twisted pair or fiber optic lines or satellite transmission. It uses a variation of High Speed Data Link Control (HDLC) for packet encapsulation.

    PPP is usually preferred over the earlier de facto standard Serial Line Internet Protocol (SLIP) because it can handle synchronous as well as asynchronous communication. PPP can share a line with other users and it has error detection that SLIP lacks. Where a choice is possible, PPP is preferred.

    Point-to-point protocol

    X.25

    X.25 is an ITU-T standard protocol suite for packet switched wide area network (WAN) communication.
    X.25 is a packet switching technology which uses carrier switch to provide connectivity for many different networks.
    Subscribers are charged based on amount of bandwidth they use. Data are divided into 128 bytes and encapsulated in High Level Data Link Control (HDLC).
    X.25 works at network and data link layer of an OSI model.

    CISA Certified Information Systems Auditor Part 68 Q01 133
    CISA Certified Information Systems Auditor Part 68 Q01 133

    X.25

    Frame Relay

    Works on a packet switching
    Operates at data link layer of an OSI model
    Companies that pay more to ensure that a higher level of bandwidth will always be available, pay a committed information rate or CIR

    Two main types of equipment’s are used in Frame Relay
    1. Data Terminal Equipment (DTE) – Usually a customer owned device that provides a connectivity between company’s own network and the frame relay’s network.

    2. Data Circuit Terminal Equipment (DCE) – Service provider device that does the actual data transmission and switching in the frame relay cloud.

    The Frame relay cloud is the collection of DCE that provides that provides switching and data communication functionality. Frame relay is any to any service.

    CISA Certified Information Systems Auditor Part 68 Q01 134
    CISA Certified Information Systems Auditor Part 68 Q01 134

    Frame Relay

    Integrated Service Digital Network

    Enables data, voice and other types of traffic to travel over a medium in a digital manner previously used only for analog voice transmission.
    Same copper telephone wire is used.
    Provide digital point-to-point circuit switching medium.

    CISA Certified Information Systems Auditor Part 68 Q01 135
    CISA Certified Information Systems Auditor Part 68 Q01 135

    ISDN

    Asynchronous Transfer Mode (ATM)

    Uses Cell switching method
    High speed network technology used for LAN, MAN and WAN
    Like a frame relay it is connection oriented technology which creates and uses fixed channel
    Data are segmented into fixed size cell of 53 bytes
    Some companies have replaces FDDI back-end with ATM

    CISA Certified Information Systems Auditor Part 68 Q01 136
    CISA Certified Information Systems Auditor Part 68 Q01 136

    Asynchronous Transfer Mode

    Multiprotocol Label Switching (MPLS)
    Multiprotocol Label Switching (MPLS) is a standards-approved technology for speeding up network traffic flow and making it easier to manage. MPLS involves setting up a specific path for a given sequence of packets, identified by a label put in each packet, thus saving the time needed for a router to look up the address to the next node to forward the packet to. MPLS is called multiprotocol because it works with the Internet Protocol (IP), Asynchronous Transport Mode (ATM), and frame relay network protocols. With reference to the standard model for a network (the Open Systems Interconnection, or OSI model), MPLS allows most packets to be forwarded at the Layer 2 (switching) level rather than at the Layer 3 (routing) level. In addition to moving traffic faster overall, MPLS makes it easy to manage a network for quality of service (QoS). For these reasons, the technique is expected to be readily adopted as networks begin to carry more and different mixtures of traffic.

    MPLS

    CISA Certified Information Systems Auditor Part 68 Q01 137
    CISA Certified Information Systems Auditor Part 68 Q01 137

    The following answers are incorrect:
    The other options presented correctly describes Asynchronous Transfer Mode.

    Reference:
    CISA review manual 2014 page number 266

  2. Which of the following technique is used for speeding up network traffic flow and making it easier to manage?

    • Point-to-point protocol
    • X.25
    • MPLS
    • ISDN
    Explanation:

    Multiprotocol Label Switching (MPLS) is a standards-approved technology for speeding up network traffic flow and making it easier to manage. MPLS involves setting up a specific path for a given sequence of packets, identified by a label put in each packet, thus saving the time needed for a router to look up the address to the next node to forward the packet to. MPLS is called multiprotocol because it works with the Internet Protocol (IP), Asynchronous Transport Mode (ATM), and frame relay network protocols. With reference to the standard model for a network (the Open Systems Interconnection, or OSI model), MPLS allows most packets to be forwarded at the Layer 2 (switching) level rather than at the Layer 3 (routing) level. In addition to moving traffic faster overall, MPLS makes it easy to manage a network for quality of service (QoS). For these reasons, the technique is expected to be readily adopted as networks begin to carry more and different mixtures of traffic.

    For your exam you should know below information about WAN Technologies:

    Point-to-point protocol
    PPP (Point-to-Point Protocol) is a protocol for communication between two computers using a serial interface, typically a personal computer connected by phone line to a server. For example, your Internet server provider may provide you with a PPP connection so that the provider’s server can respond to your requests, pass them on to the Internet, and forward your requested Internet responses back to you. PPP uses the Internet protocol (IP) (and is designed to handle others). It is sometimes considered a member of the TCP/IP suite of protocols. Relative to the Open Systems Interconnection (OSI) reference model, PPP provides layer 2 (data-link layer) service. Essentially, it packages your computer’s TCP/IP packets and forwards them to the server where they can actually be put on the Internet.

    PPP is a full-duplex protocol that can be used on various physical media, including twisted pair or fiber optic lines or satellite transmission. It uses a variation of High Speed Data Link Control (HDLC) for packet encapsulation.

    PPP is usually preferred over the earlier de facto standard Serial Line Internet Protocol (SLIP) because it can handle synchronous as well as asynchronous communication. PPP can share a line with other users and it has error detection that SLIP lacks. Where a choice is possible, PPP is preferred.

    Point-to-point protocol

    X.25

    X.25 is an ITU-T standard protocol suite for packet switched wide area network (WAN) communication.
    X.25 is a packet switching technology which uses carrier switch to provide connectivity for many different networks.
    Subscribers are charged based on amount of bandwidth they use. Data are divided into 128 bytes and encapsulated in High Level Data Link Control (HDLC).
    X.25 works at network and data link layer of an OSI model.

    CISA Certified Information Systems Auditor Part 68 Q02 138
    CISA Certified Information Systems Auditor Part 68 Q02 138

    X.25

    Frame Relay
    Works on a packet switching
    Operates at data link layer of an OSI model
    Companies that pay more to ensure that a higher level of bandwidth will always be available, pay a committed information rate or CIR

    Two main types of equipment’s are used in Frame Relay
    1. Data Terminal Equipment (DTE) – Usually a customer owned device that provides a connectivity between company’s own network and the frame relay’s network.

    2. Data Circuit Terminal Equipment (DCE) – Service provider device that does the actual data transmission and switching in the frame relay cloud.

    The Frame relay cloud is the collection of DCE that provides that provides switching and data communication functionality. Frame relay is any to any service.

    Frame Relay
    Integrated Service Digital Network

    Enables data, voice and other types of traffic to travel over a medium in a digital manner previously used only for analog voice transmission.
    Same copper telephone wire is used.
    Provide digital point-to-point circuit switching medium.

    ISDN

    Asynchronous Transfer Mode (ATM)

    Uses Cell switching method
    High speed network technology used for LAN, MAN and WAN
    Like a frame relay it is connection oriented technology which creates and uses fixed channel
    Data are segmented into fixed size cell of 53 bytes
    Some companies have replaces FDDI back-end with ATM

    Asynchronous Transfer Mode

    CISA Certified Information Systems Auditor Part 68 Q02 139
    CISA Certified Information Systems Auditor Part 68 Q02 139

    Multiprotocol Label Switching (MPLS)
    Multiprotocol Label Switching (MPLS) is a standards-approved technology for speeding up network traffic flow and making it easier to manage. MPLS involves setting up a specific path for a given sequence of packets, identified by a label put in each packet, thus saving the time needed for a router to look up the address to the next node to forward the packet to. MPLS is called multiprotocol because it works with the Internet Protocol (IP), Asynchronous Transport Mode (ATM), and frame relay network protocols. With reference to the standard model for a network (the Open Systems Interconnection, or OSI model), MPLS allows most packets to be forwarded at the Layer 2 (switching) level rather than at the Layer 3 (routing) level. In addition to moving traffic faster overall, MPLS makes it easy to manage a network for quality of service (QoS). For these reasons, the technique is expected to be readily adopted as networks begin to carry more and different mixtures of traffic.

    MPLS

    CISA Certified Information Systems Auditor Part 68 Q02 140
    CISA Certified Information Systems Auditor Part 68 Q02 140

    The following answers are incorrect:

    X.25 – X.25 is an ITU-T standard protocol suite for packet switched wide area network (WAN) communication.X.25 is a packet switching technology which uses carrier switch to provide connectivity for many different networks.

    Point-to-point protocol – PPP (Point-to-Point Protocol) is a protocol for communication between two computers using a serial interface, typically a personal computer connected by phone line to a server.

    ISDN -Enables data, voice and other types of traffic to travel over a medium in a digital manner previously used only for analog voice transmission.

    Reference:
    CISA review manual 2014 page number 266

  3. An IS auditor should know information about different network transmission media. Which of the following transmission media is used for short distance transmission?

    • Copper cable
    • Fiber Optics
    • Satellite Radio Link
    • Satellite Radio Link
    Explanation:

    Copper cable is very simple to install and easy to tap. It is used mostly for short distance and supports voice and data.

    For your exam you should know below information about transmission media:

    Copper Cable
    Copper cable is very simple to install and easy to tap. It is used mostly for short distance and supports voice and data.
    Copper has been used in electric wiring since the invention of the electromagnet and the telegraph in the 1820s.The invention of the telephone in 1876 created further demand for copper wire as an electrical conductor.
    Copper is the electrical conductor in many categories of electrical wiring. Copper wire is used in power generation, power transmission, power distribution, telecommunications, electronics circuitry, and countless types of electrical equipment. Copper and its alloys are also used to make electrical contacts. Electrical wiring in buildings is the most important market for the copper industry. Roughly half of all copper mined is used to manufacture electrical wire and cable conductors.
    Copper Cable

    CISA Certified Information Systems Auditor Part 68 Q03 141
    CISA Certified Information Systems Auditor Part 68 Q03 141

    Coaxial cable
    Coaxial cable, or coax (pronounced ‘ko.aks), is a type of cable that has an inner conductor surrounded by a tubular insulating layer, surrounded by a tubular conducting shield. Many coaxial cables also have an insulating outer sheath or jacket. The term coaxial comes from the inner conductor and the outer shield sharing a geometric axis. Coaxial cable was invented by English engineer and mathematician Oliver Heaviside, who patented the design in 1880.Coaxial cable differs from other shielded cable used for carrying lower-frequency signals, such as audio signals, in that the dimensions of the cable are controlled to give a precise, constant conductor spacing, which is needed for it to function efficiently as a radio frequency transmission line.

    Coaxial cable is expensive and does not support many LAN’s. It supports data and video.

    CISA Certified Information Systems Auditor Part 68 Q03 142
    CISA Certified Information Systems Auditor Part 68 Q03 142

    Coaxial Cable

    Fiber optics
    An optical fiber cable is a cable containing one or more optical fibers that are used to carry light. The optical fiber elements are typically individually coated with plastic layers and contained in a protective tube suitable for the environment where the cable will be deployed. Different types of cable are used for different applications, for example long distance telecommunication, or providing a high-speed data connection between different parts of a building.

    Fiber optics used for long distance, hard to splice, not vulnerable to cross talk and difficult to tap. It supports voice data, image and video.

    Fiber Optics

    CISA Certified Information Systems Auditor Part 68 Q03 143
    CISA Certified Information Systems Auditor Part 68 Q03 143

    Radio System
    Radio systems are used for short distance, cheap and easy to intercept.
    Radio is the radiation (wireless transmission) of electromagnetic signals through the atmosphere or free space.

    Information, such as sound, is carried by systematically changing (modulating) some property of the radiated waves, such as their amplitude, frequency, phase, or pulse width. When radio waves strike an electrical conductor, the oscillating fields induce an alternating current in the conductor. The information in the waves can be extracted and transformed back into its original form.

    Microwave radio system
    Microwave transmission refers to the technology of transmitting information or energy by the use of radio waves whose wavelengths are conveniently measured in small numbers of centimeter; these are called microwaves.
    Microwaves are widely used for point-to-point communications because their small wavelength allows conveniently-sized antennas to direct them in narrow beams, which can be pointed directly at the receiving antenna. This allows nearby microwave equipment to use the same frequencies without interfering with each other, as lower frequency radio waves do. Another advantage is that the high frequency of microwaves gives the microwave band a very large information-carrying capacity; the microwave band has a bandwidth 30 times that of all the rest of the radio spectrum below it. A disadvantage is that microwaves are limited to line of sight propagation; they cannot pass around hills or mountains as lower frequency radio waves can.

    Microwave radio transmission is commonly used in point-to-point communication systems on the surface of the Earth, in satellite communications, and in deep space radio communications. Other parts of the microwave radio band are used for radars, radio navigation systems, sensor systems, and radio astronomy.

    Microwave radio systems are carriers for voice data signal, cheap and easy to tap.
    Microwave Radio System

    CISA Certified Information Systems Auditor Part 68 Q03 144
    CISA Certified Information Systems Auditor Part 68 Q03 144

    Satellite Radio Link
    Satellite radio is a radio service broadcast from satellites primarily to cars, with the signal broadcast nationwide, across a much wider geographical area than terrestrial radio stations. It is available by subscription, mostly commercial free, and offers subscribers more stations and a wider variety of programming options than terrestrial radio.

    Satellite radio link uses transponder to send information and easy to intercept.

    The following answers are incorrect:

    Fiber optics – Fiber optics cables are used for long distance, hard to splice, not vulnerable to cross talk and difficult to tap. It supports voice data, image and video.

    Radio System – Radio systems are used for short distance, cheap and easy to tap.

    Satellite Radio Link – Satellite radio link uses transponder to send information and easy to tap.

    Reference:
    CISA review manual 2014 page number 265

  4. Which of the following transmission media is MOST difficult to tap?

    • Copper cable
    • Fiber Optics
    • Satellite Radio Link
    • Radio System
    Explanation:

    Fiber optics cables are used for long distance, hard to splice, not vulnerable to cross talk and difficult to tap. It supports voice data, image and video.

    For your exam you should know below information about transmission media:

    Copper Cable
    Copper cable is very simple to install and easy to tap. It is used mostly for short distance and supports voice and data.
    Copper has been used in electric wiring since the invention of the electromagnet and the telegraph in the 1820s.The invention of the telephone in 1876 created further demand for copper wire as an electrical conductor.
    Copper is the electrical conductor in many categories of electrical wiring. Copper wire is used in power generation, power transmission, power distribution, telecommunications, electronics circuitry, and countless types of electrical equipment. Copper and its alloys are also used to make electrical contacts. Electrical wiring in buildings is the most important market for the copper industry. Roughly half of all copper mined is used to manufacture electrical wire and cable conductors.
    Copper Cable

    CISA Certified Information Systems Auditor Part 68 Q04 145
    CISA Certified Information Systems Auditor Part 68 Q04 145

    Coaxial cable
    Coaxial cable, or coax (pronounced ‘ko.aks), is a type of cable that has an inner conductor surrounded by a tubular insulating layer, surrounded by a tubular conducting shield. Many coaxial cables also have an insulating outer sheath or jacket. The term coaxial comes from the inner conductor and the outer shield sharing a geometric axis. Coaxial cable was invented by English engineer and mathematician Oliver Heaviside, who patented the design in 1880.Coaxial cable differs from other shielded cable used for carrying lower-frequency signals, such as audio signals, in that the dimensions of the cable are controlled to give a precise, constant conductor spacing, which is needed for it to function efficiently as a radio frequency transmission line.

    Coaxial cable is expensive and does not support many LAN’s. It supports data and video.

    CISA Certified Information Systems Auditor Part 68 Q04 146
    CISA Certified Information Systems Auditor Part 68 Q04 146

    Coaxial Cable

    Fiber optics
    An optical fiber cable is a cable containing one or more optical fibers that are used to carry light. The optical fiber elements are typically individually coated with plastic layers and contained in a protective tube suitable for the environment where the cable will be deployed. Different types of cable are used for different applications, for example long distance telecommunication, or providing a high-speed data connection between different parts of a building.

    Fiber optics used for long distance, hard to splice, not vulnerable to cross talk and difficult to tap. It supports voice data, image and video.

    Fiber Optics

    CISA Certified Information Systems Auditor Part 68 Q04 147
    CISA Certified Information Systems Auditor Part 68 Q04 147

    Microwave radio system
    Microwave transmission refers to the technology of transmitting information or energy by the use of radio waves whose wavelengths are conveniently measured in small numbers of centimeter; these are called microwaves.
    Microwaves are widely used for point-to-point communications because their small wavelength allows conveniently-sized antennas to direct them in narrow beams, which can be pointed directly at the receiving antenna. This allows nearby microwave equipment to use the same frequencies without interfering with each other, as lower frequency radio waves do. Another advantage is that the high frequency of microwaves gives the microwave band a very large information-carrying capacity; the microwave band has a bandwidth 30 times that of all the rest of the radio spectrum below it. A disadvantage is that microwaves are limited to line of sight propagation; they cannot pass around hills or mountains as lower frequency radio waves can.

    Microwave radio transmission is commonly used in point-to-point communication systems on the surface of the Earth, in satellite communications, and in deep space radio communications. Other parts of the microwave radio band are used for radars, radio navigation systems, sensor systems, and radio astronomy.

    Microwave radio systems are carriers for voice data signal, cheap and easy to intercept.

    Microwave Radio System

    CISA Certified Information Systems Auditor Part 68 Q04 148
    CISA Certified Information Systems Auditor Part 68 Q04 148

    Satellite Radio Link
    Satellite radio is a radio service broadcast from satellites primarily to cars, with the signal broadcast nationwide, across a much wider geographical area than terrestrial radio stations. It is available by subscription, mostly commercial free, and offers subscribers more stations and a wider variety of programming options than terrestrial radio.

    Satellite radio link uses transponder to send information and easy to intercept.

    Radio System
    Radio systems are used for short distance, cheap and easy to intercept.
    Radio is the radiation (wireless transmission) of electromagnetic signals through the atmosphere or free space.

    Information, such as sound, is carried by systematically changing (modulating) some property of the radiated waves, such as their amplitude, frequency, phase, or pulse width. When radio waves strike an electrical conductor, the oscillating fields induce an alternating current in the conductor. The information in the waves can be extracted and transformed back into its original form.

    The following answers are incorrect:

    Copper Cable- Copper cable is very simple to install and easy to tap. It is used mostly for short distance and supports voice and data.

    Radio System – Radio systems are used for short distance, cheap and easy to tap.

    Satellite Radio Link – Satellite radio link uses transponder to send information and easy to tap.

    Reference:
    CISA review manual 2014 page number 265

  5. Which of the following transmission media uses a transponder to send information?

    • Copper cable
    • Fiber Optics
    • Satellite Radio Link
    • Coaxial cable
    Explanation:

    Satellite radio link uses transponder to send information and are easy to intercept.

    For your exam you should know below information about transmission media:

    Copper Cable
    Copper cable is very simple to install and easy to tap. It is used mostly for short distance and supports voice and data.
    Copper has been used in electric wiring since the invention of the electromagnet and the telegraph in the 1820s.The invention of the telephone in 1876 created further demand for copper wire as an electrical conductor.
    Copper is the electrical conductor in many categories of electrical wiring. Copper wire is used in power generation, power transmission, power distribution, telecommunications, electronics circuitry, and countless types of electrical equipment. Copper and its alloys are also used to make electrical contacts. Electrical wiring in buildings is the most important market for the copper industry. Roughly half of all copper mined is used to manufacture electrical wire and cable conductors.
    Copper Cable

    CISA Certified Information Systems Auditor Part 68 Q05 149
    CISA Certified Information Systems Auditor Part 68 Q05 149

    Coaxial cable
    Coaxial cable, or coax (pronounced ‘ko.aks), is a type of cable that has an inner conductor surrounded by a tubular insulating layer, surrounded by a tubular conducting shield. Many coaxial cables also have an insulating outer sheath or jacket. The term coaxial comes from the inner conductor and the outer shield sharing a geometric axis. Coaxial cable was invented by English engineer and mathematician Oliver Heaviside, who patented the design in 1880.Coaxial cable differs from other shielded cable used for carrying lower-frequency signals, such as audio signals, in that the dimensions of the cable are controlled to give a precise, constant conductor spacing, which is needed for it to function efficiently as a radio frequency transmission line.

    Coaxial cable is expensive and does not support many LAN’s. It supports data and video.

    CISA Certified Information Systems Auditor Part 68 Q05 150
    CISA Certified Information Systems Auditor Part 68 Q05 150

    Coaxial Cable

    Fiber optics
    An optical fiber cable is a cable containing one or more optical fibers that are used to carry light. The optical fiber elements are typically individually coated with plastic layers and contained in a protective tube suitable for the environment where the cable will be deployed. Different types of cable are used for different applications, for example long distance telecommunication, or providing a high-speed data connection between different parts of a building.

    Fiber optics used for long distance, hard to splice, not vulnerable to cross talk and difficult to tap. It supports voice data, image and video.

    Fiber Optics

    CISA Certified Information Systems Auditor Part 68 Q05 151
    CISA Certified Information Systems Auditor Part 68 Q05 151

    Microwave radio system
    Microwave transmission refers to the technology of transmitting information or energy by the use of radio waves whose wavelengths are conveniently measured in small numbers of centimeter; these are called microwaves.
    Microwaves are widely used for point-to-point communications because their small wavelength allows conveniently-sized antennas to direct them in narrow beams, which can be pointed directly at the receiving antenna. This allows nearby microwave equipment to use the same frequencies without interfering with each other, as lower frequency radio waves do. Another advantage is that the high frequency of microwaves gives the microwave band a very large information-carrying capacity; the microwave band has a bandwidth 30 times that of all the rest of the radio spectrum below it. A disadvantage is that microwaves are limited to line of sight propagation; they cannot pass around hills or mountains as lower frequency radio waves can.

    Microwave radio transmission is commonly used in point-to-point communication systems on the surface of the Earth, in satellite communications, and in deep space radio communications. Other parts of the microwave radio band are used for radars, radio navigation systems, sensor systems, and radio astronomy.

    Microwave radio systems are carriers for voice data signal, cheap and easy to intercept.

    Microwave Radio System

    CISA Certified Information Systems Auditor Part 68 Q05 152
    CISA Certified Information Systems Auditor Part 68 Q05 152

    Satellite Radio Link
    Satellite radio is a radio service broadcast from satellites primarily to cars, with the signal broadcast nationwide, across a much wider geographical area than terrestrial radio stations. It is available by subscription, mostly commercial free, and offers subscribers more stations and a wider variety of programming options than terrestrial radio.

    Satellite radio link uses transponder to send information and easy to intercept.

    Radio System
    Radio systems are used for short distance, cheap and easy to intercept.
    Radio is the radiation (wireless transmission) of electromagnetic signals through the atmosphere or free space.

    Information, such as sound, is carried by systematically changing (modulating) some property of the radiated waves, such as their amplitude, frequency, phase, or pulse width. When radio waves strike an electrical conductor, the oscillating fields induce an alternating current in the conductor. The information in the waves can be extracted and transformed back into its original form.

    The following answers are incorrect:

    Copper Cable- Copper cable is very simple to install and easy to tap. It is used mostly for short distance and supports voice and data.

    Radio System – Radio systems are used for short distance, cheap and easy to tap.

    Satellite Radio Link – Satellite radio link uses transponder to send information and easy to tap.

    Reference:
    CISA review manual 2014 page number 265

  6. Which of the following transmission media is LEAST vulnerable to cross talk?

    • Copper cable
    • Fiber Optics
    • Satellite Radio Link
    • Coaxial cable
    Explanation:

    Fiber optics cables are used for long distance, hard to splice, not vulnerable to cross talk and difficult to tap. It supports voice data, image and video.

    For your exam you should know below information about transmission media:

    Copper Cable
    Copper cable is very simple to install and easy to tap. It is used mostly for short distance and supports voice and data.
    Copper has been used in electric wiring since the invention of the electromagnet and the telegraph in the 1820s.The invention of the telephone in 1876 created further demand for copper wire as an electrical conductor.
    Copper is the electrical conductor in many categories of electrical wiring. Copper wire is used in power generation, power transmission, power distribution, telecommunications, electronics circuitry, and countless types of electrical equipment. Copper and its alloys are also used to make electrical contacts. Electrical wiring in buildings is the most important market for the copper industry. Roughly half of all copper mined is used to manufacture electrical wire and cable conductors.
    Copper Cable

    CISA Certified Information Systems Auditor Part 68 Q06 153
    CISA Certified Information Systems Auditor Part 68 Q06 153

    Coaxial cable
    Coaxial cable, or coax (pronounced ‘ko.aks), is a type of cable that has an inner conductor surrounded by a tubular insulating layer, surrounded by a tubular conducting shield. Many coaxial cables also have an insulating outer sheath or jacket. The term coaxial comes from the inner conductor and the outer shield sharing a geometric axis. Coaxial cable was invented by English engineer and mathematician Oliver Heaviside, who patented the design in 1880.Coaxial cable differs from other shielded cable used for carrying lower-frequency signals, such as audio signals, in that the dimensions of the cable are controlled to give a precise, constant conductor spacing, which is needed for it to function efficiently as a radio frequency transmission line.

    Coaxial cable is expensive and does not support many LAN’s. It supports data and video.

    CISA Certified Information Systems Auditor Part 68 Q06 154
    CISA Certified Information Systems Auditor Part 68 Q06 154

    Coaxial Cable

    Fiber optics
    An optical fiber cable is a cable containing one or more optical fibers that are used to carry light. The optical fiber elements are typically individually coated with plastic layers and contained in a protective tube suitable for the environment where the cable will be deployed. Different types of cable are used for different applications, for example long distance telecommunication, or providing a high-speed data connection between different parts of a building.

    Fiber optics used for long distance, hard to splice, not vulnerable to cross talk and difficult to tap. It supports voice data, image and video.

    Fiber Optics

    CISA Certified Information Systems Auditor Part 68 Q06 155
    CISA Certified Information Systems Auditor Part 68 Q06 155

    Microwave radio system
    Microwave transmission refers to the technology of transmitting information or energy by the use of radio waves whose wavelengths are conveniently measured in small numbers of centimeter; these are called microwaves.
    Microwaves are widely used for point-to-point communications because their small wavelength allows conveniently-sized antennas to direct them in narrow beams, which can be pointed directly at the receiving antenna. This allows nearby microwave equipment to use the same frequencies without interfering with each other, as lower frequency radio waves do. Another advantage is that the high frequency of microwaves gives the microwave band a very large information-carrying capacity; the microwave band has a bandwidth 30 times that of all the rest of the radio spectrum below it. A disadvantage is that microwaves are limited to line of sight propagation; they cannot pass around hills or mountains as lower frequency radio waves can.

    Microwave radio transmission is commonly used in point-to-point communication systems on the surface of the Earth, in satellite communications, and in deep space radio communications. Other parts of the microwave radio band are used for radars, radio navigation systems, sensor systems, and radio astronomy.

    Microwave radio systems are carriers for voice data signal, cheap and easy to intercept.

    Microwave Radio System

    CISA Certified Information Systems Auditor Part 68 Q06 156
    CISA Certified Information Systems Auditor Part 68 Q06 156

    Satellite Radio Link
    Satellite radio is a radio service broadcast from satellites primarily to cars, with the signal broadcast nationwide, across a much wider geographical area than terrestrial radio stations. It is available by subscription, mostly commercial free, and offers subscribers more stations and a wider variety of programming options than terrestrial radio.

    Satellite radio link uses transponder to send information and easy to intercept.

    Radio System
    Radio systems are used for short distance, cheap and easy to tap.
    Radio is the radiation (wireless transmission) of electromagnetic signals through the atmosphere or free space.

    Information, such as sound, is carried by systematically changing (modulating) some property of the radiated waves, such as their amplitude, frequency, phase, or pulse width. When radio waves strike an electrical conductor, the oscillating fields induce an alternating current in the conductor. The information in the waves can be extracted and transformed back into its original form.

    The following answers are incorrect:

    Copper Cable- Copper cable is very simple to install and easy to tap. It is used mostly for short distance and supports voice and data.

    Satellite Radio Link – Satellite radio link uses transponder to send information and easy to tap.

    Coaxial cable – Coaxial cable are expensive and does not support many LAN’s. It supports data and video

    Reference:
    CISA review manual 2014 page number 265

  7. In which of the following transmission media it is MOST difficult to modify the information traveling across the network?

    • Copper cable
    • Fiber Optics
    • Satellite Radio Link
    • Coaxial cable
    Explanation:

    Fiber optics cables are used for long distance, hard to splice, not vulnerable to cross talk and difficult to tap. It supports voice data, image and video.

    For your exam you should know below information about transmission media:

    Copper Cable
    Copper cable is very simple to install and easy to tap. It is used mostly for short distance and supports voice and data.
    Copper has been used in electric wiring since the invention of the electromagnet and the telegraph in the 1820s.The invention of the telephone in 1876 created further demand for copper wire as an electrical conductor.
    Copper is the electrical conductor in many categories of electrical wiring. Copper wire is used in power generation, power transmission, power distribution, telecommunications, electronics circuitry, and countless types of electrical equipment. Copper and its alloys are also used to make electrical contacts. Electrical wiring in buildings is the most important market for the copper industry. Roughly half of all copper mined is used to manufacture electrical wire and cable conductors.
    Copper Cable

    CISA Certified Information Systems Auditor Part 68 Q07 157
    CISA Certified Information Systems Auditor Part 68 Q07 157

     

    Coaxial cable
    Coaxial cable, or coax (pronounced ‘ko.aks), is a type of cable that has an inner conductor surrounded by a tubular insulating layer, surrounded by a tubular conducting shield. Many coaxial cables also have an insulating outer sheath or jacket. The term coaxial comes from the inner conductor and the outer shield sharing a geometric axis. Coaxial cable was invented by English engineer and mathematician Oliver Heaviside, who patented the design in 1880.Coaxial cable differs from other shielded cable used for carrying lower-frequency signals, such as audio signals, in that the dimensions of the cable are controlled to give a precise, constant conductor spacing, which is needed for it to function efficiently as a radio frequency transmission line.
    Coaxial cable is expensive and does not support many LAN’s. It supports data and video.

    Coaxial Cable

    CISA Certified Information Systems Auditor Part 68 Q07 158
    CISA Certified Information Systems Auditor Part 68 Q07 158

    Fiber optics
    An optical fiber cable is a cable containing one or more optical fibers that are used to carry light. The optical fiber elements are typically individually coated with plastic layers and contained in a protective tube suitable for the environment where the cable will be deployed. Different types of cable are used for different applications, for example long distance telecommunication, or providing a high-speed data connection between different parts of a building.

    Fiber optics used for long distance, hard to splice, not vulnerable to cross talk and difficult to tap. It supports voice data, image and video.
    Radio System
    Radio systems are used for short distance, cheap and easy to tap.
    Radio is the radiation (wireless transmission) of electromagnetic signals through the atmosphere or free space.

    Information, such as sound, is carried by systematically changing (modulating) some property of the radiated waves, such as their amplitude, frequency, phase, or pulse width. When radio waves strike an electrical conductor, the oscillating fields induce an alternating current in the conductor. The information in the waves can be extracted and transformed back into its original form.

    Fiber Optics

    CISA Certified Information Systems Auditor Part 68 Q07 159
    CISA Certified Information Systems Auditor Part 68 Q07 159

    Microwave radio system
    Microwave transmission refers to the technology of transmitting information or energy by the use of radio waves whose wavelengths are conveniently measured in small numbers of centimeter; these are called microwaves.
    Microwaves are widely used for point-to-point communications because their small wavelength allows conveniently-sized antennas to direct them in narrow beams, which can be pointed directly at the receiving antenna. This allows nearby microwave equipment to use the same frequencies without interfering with each other, as lower frequency radio waves do. Another advantage is that the high frequency of microwaves gives the microwave band a very large information-carrying capacity; the microwave band has a bandwidth 30 times that of all the rest of the radio spectrum below it. A disadvantage is that microwaves are limited to line of sight propagation; they cannot pass around hills or mountains as lower frequency radio waves can.

    Microwave radio transmission is commonly used in point-to-point communication systems on the surface of the Earth, in satellite communications, and in deep space radio communications. Other parts of the microwave radio band are used for radars, radio navigation systems, sensor systems, and radio astronomy.

    Microwave radio systems are carriers for voice data signal, cheap and easy to tap.

    Microwave Radio System

    CISA Certified Information Systems Auditor Part 68 Q07 160
    CISA Certified Information Systems Auditor Part 68 Q07 160

    Satellite Radio Link
    Satellite radio is a radio service broadcast from satellites primarily to cars, with the signal broadcast nationwide, across a much wider geographical area than terrestrial radio stations. It is available by subscription, mostly commercial free, and offers subscribers more stations and a wider variety of programming options than terrestrial radio.

    Satellite radio link uses transponder to send information and easy to tap.

    The following answers are incorrect:

    Copper Cable- Copper cable is very simple to install and easy to tap. It is used mostly for short distance and supports voice and data.

    Satellite Radio Link – Satellite radio link uses transponder to send information and easy to tap.

    Coaxial cable – Coaxial cable are expensive and does not support many LAN’s. It supports data and video

    Reference:

    CISA review manual 2014 page number 265

  8. Which of the following is the INCORRECT Layer to Protocol mapping used in the DOD TCP/IP model?

    • Application layer – Telnet
    • Transport layer – ICMP
    • Internet layer – IP
    • Network Access layer – Ethernet
    Explanation:

    The keyword INCORRECT is used within the question. You need to find out the incorrect Layer to Protocol mapping.

    The ICMP protocol works at Internet layer of the DoD TCP/IP model, not at the Transport Layer.

    For your exam you should know below information about the TCP/IP models:
    Network Models

    CISA Certified Information Systems Auditor Part 68 Q08 161
    CISA Certified Information Systems Auditor Part 68 Q08 161

    Layer 4. Application Layer
    Application layer is the top most layer of four layer TCP/IP model. Application layer is present on the top of the Transport layer. Application layer defines TCP/IP application protocols and how host programs interface with Transport layer services to use the network.

    Application layer includes all the higher-level protocols like DNS (Domain Naming System), HTTP (Hypertext Transfer Protocol), Telnet, SSH, FTP (File Transfer Protocol), TFTP (Trivial File Transfer Protocol), SNMP (Simple Network Management Protocol), SMTP (Simple Mail Transfer Protocol) , DHCP (Dynamic Host Configuration Protocol), X Windows, RDP (Remote Desktop Protocol) etc.

    Layer 3. Transport Layer
    Transport Layer is the third layer of the four layer TCP/IP model. The position of the Transport layer is between Application layer and Internet layer. The purpose of Transport layer is to permit devices on the source and destination hosts to carry on a conversation. Transport layer defines the level of service and status of the connection used when transporting data.

    The main protocols included at Transport layer are TCP (Transmission Control Protocol) and UDP (User Datagram Protocol).

    Layer 2. Internet Layer
    Internet Layer is the second layer of the four layer TCP/IP model. The position of Internet layer is between Network Access Layer and Transport layer. Internet layer pack data into data packets known as IP datagram’s, which contain source and destination address (logical address or IP address) information that is used to forward the datagram’s between hosts and across networks. The Internet layer is also responsible for routing of IP datagram’s.

    Packet switching network depends upon a connectionless internetwork layer. This layer is known as Internet layer. Its job is to allow hosts to insert packets into any network and have them to deliver independently to the destination. At the destination side data packets may appear in a different order than they were sent. It is the job of the higher layers to rearrange them in order to deliver them to proper network applications operating at the Application layer.

    The main protocols included at Internet layer are IP (Internet Protocol), ICMP (Internet Control Message Protocol), ARP (Address Resolution Protocol), RARP (Reverse Address Resolution Protocol) and IGMP (Internet Group Management Protocol).

    Layer 1. Network Access Layer
    Network Access Layer is the first layer of the four layer TCP/IP model. Network Access Layer defines details of how data is physically sent through the network, including how bits are electrically or optically signaled by hardware devices that interface directly with a network medium, such as coaxial cable, optical fiber, or twisted pair copper wire.

    The protocols included in Network Access Layer are Ethernet, Token Ring, FDDI, X.25, Frame Relay etc.

    The most popular LAN architecture among those listed above is Ethernet. Ethernet uses an Access Method called CSMA/CD (Carrier Sense Multiple Access/Collision Detection) to access the media, when Ethernet operates in a shared media. An Access Method determines how a host will place data on the medium.

    IN CSMA/CD Access Method, every host has equal access to the medium and can place data on the wire when the wire is free from network traffic. When a host wants to place data on the wire, it will check the wire to find whether another host is already using the medium. If there is traffic already in the medium, the host will wait and if there is no traffic, it will place the data in the medium. But, if two systems place data on the medium at the same instance, they will collide with each other, destroying the data. If the data is destroyed during transmission, the data will need to be retransmitted. After collision, each host will wait for a small interval of time and again the data will be retransmitted.

    Protocol Data Unit (PDU):

    CISA Certified Information Systems Auditor Part 68 Q08 162
    CISA Certified Information Systems Auditor Part 68 Q08 162

    The following answers are incorrect:

    The other options correctly describe the Layer to Protocol mapping of the DoD TCP/IP model protocols.

    Reference:
    CISA review manual 2014 page number 272

  9. Which of the following protocol does NOT work at the Application layer of the TCP/IP Models?

    • HTTP
    • FTP
    • NTP
    • TCP
    Explanation:

    The NOT keyword is used in the question. You need to find out a protocol which does not work at application layer. TCP protocol works at transport layer of a TCP/IP models.

    For your exam you should know below information about TCP/IP model:

    Network Models

    CISA Certified Information Systems Auditor Part 68 Q09 163
    CISA Certified Information Systems Auditor Part 68 Q09 163

    Layer 4. Application Layer
    Application layer is the top most layer of four layer TCP/IP model. Application layer is present on the top of the Transport layer. Application layer defines TCP/IP application protocols and how host programs interface with Transport layer services to use the network.

    Application layer includes all the higher-level protocols like DNS (Domain Naming System), HTTP (Hypertext Transfer Protocol), Telnet, SSH, FTP (File Transfer Protocol), TFTP (Trivial File Transfer Protocol), SNMP (Simple Network Management Protocol), SMTP (Simple Mail Transfer Protocol) , DHCP (Dynamic Host Configuration Protocol), X Windows, RDP (Remote Desktop Protocol) etc.

    Layer 3. Transport Layer

    Transport Layer is the third layer of the four layer TCP/IP model. The position of the Transport layer is between Application layer and Internet layer. The purpose of Transport layer is to permit devices on the source and destination hosts to carry on a conversation. Transport layer defines the level of service and status of the connection used when transporting data.

    The main protocols included at Transport layer are TCP (Transmission Control Protocol) and UDP (User Datagram Protocol).

    Layer 2. Internet Layer
    Internet Layer is the second layer of the four layer TCP/IP model. The position of Internet layer is between Network Access Layer and Transport layer. Internet layer pack data into data packets known as IP datagram’s, which contain source and destination address (logical address or IP address) information that is used to forward the datagram’s between hosts and across networks. The Internet layer is also responsible for routing of IP datagram’s.

    Packet switching network depends upon a connectionless internetwork layer. This layer is known as Internet layer. Its job is to allow hosts to insert packets into any network and have them to deliver independently to the destination. At the destination side data packets may appear in a different order than they were sent. It is the job of the higher layers to rearrange them in order to deliver them to proper network applications operating at the Application layer.

    The main protocols included at Internet layer are IP (Internet Protocol), ICMP (Internet Control Message Protocol), ARP (Address Resolution Protocol), RARP (Reverse Address Resolution Protocol) and IGMP (Internet Group Management Protocol).

    Layer 1. Network Access Layer

    Network Access Layer is the first layer of the four layer TCP/IP model. Network Access Layer defines details of how data is physically sent through the network, including how bits are electrically or optically signaled by hardware devices that interface directly with a network medium, such as coaxial cable, optical fiber, or twisted pair copper wire.

    The protocols included in Network Access Layer are Ethernet, Token Ring, FDDI, X.25, Frame Relay etc.

    The most popular LAN architecture among those listed above is Ethernet. Ethernet uses an Access Method called CSMA/CD (Carrier Sense Multiple Access/Collision Detection) to access the media, when Ethernet operates in a shared media. An Access Method determines how a host will place data on the medium.

    IN CSMA/CD Access Method, every host has equal access to the medium and can place data on the wire when the wire is free from network traffic. When a host wants to place data on the wire, it will check the wire to find whether another host is already using the medium. If there is traffic already in the medium, the host will wait and if there is no traffic, it will place the data in the medium. But, if two systems place data on the medium at the same instance, they will collide with each other, destroying the data. If the data is destroyed during transmission, the data will need to be retransmitted. After collision, each host will wait for a small interval of time and again the data will be retransmitted.

    Protocol Data Unit (PDU):

    CISA Certified Information Systems Auditor Part 68 Q09 164
    CISA Certified Information Systems Auditor Part 68 Q09 164

    The following answers are incorrect:

    HTTP, FTP and NTP protocols works at application layer in TCP/IP model.

    Reference:

    CISA review manual 2014 page number 272

  10. Which of the following statement INCORRECTLY describes device and where they sit within the TCP/IP model?

    • Layer 4 switch work at Network interface layer in TCP/IP model
    • Router works at Network interface layer in TCP/IP model
    • Layer 3 switch work at Network interface layer in TCP/IP model
    • Hub works at LAN or WAN interface layer of a TCP/IP model
    Explanation:

    The keyword within the question is INCORRECTLY. You need to find out incorrect statement.

    For your exam you should know below information about TCP/IP model:

    Network models

    CISA Certified Information Systems Auditor Part 68 Q10 165
    CISA Certified Information Systems Auditor Part 68 Q10 165

    Layer 4. Application Layer
    Application layer is the top most layer of four layer TCP/IP model. Application layer is present on the top of the Transport layer. Application layer defines TCP/IP application protocols and how host programs interface with Transport layer services to use the network.

    Application layer includes all the higher-level protocols like DNS (Domain Naming System), HTTP (Hypertext Transfer Protocol), Telnet, SSH, FTP (File Transfer Protocol), TFTP (Trivial File Transfer Protocol), SNMP (Simple Network Management Protocol), SMTP (Simple Mail Transfer Protocol) , DHCP (Dynamic Host Configuration Protocol), X Windows, RDP (Remote Desktop Protocol) etc.

    Layer 3. Transport Layer
    Transport Layer is the third layer of the four layer TCP/IP model. The position of the Transport layer is between Application layer and Internet layer. The purpose of Transport layer is to permit devices on the source and destination hosts to carry on a conversation. Transport layer defines the level of service and status of the connection used when transporting data.

    The main protocols included at Transport layer are TCP (Transmission Control Protocol) and UDP (User Datagram Protocol).

    Layer 2. Internet Layer
    Internet Layer is the second layer of the four layer TCP/IP model. The position of Internet layer is between Network Access Layer and Transport layer. Internet layer pack data into data packets known as IP datagram’s, which contain source and destination address (logical address or IP address) information that is used to forward the datagram’s between hosts and across networks. The Internet layer is also responsible for routing of IP datagram’s.

    Packet switching network depends upon a connectionless internetwork layer. This layer is known as Internet layer. Its job is to allow hosts to insert packets into any network and have them to deliver independently to the destination. At the destination side data packets may appear in a different order than they were sent. It is the job of the higher layers to rearrange them in order to deliver them to proper network applications operating at the Application layer.

    The main protocols included at Internet layer are IP (Internet Protocol), ICMP (Internet Control Message Protocol), ARP (Address Resolution Protocol), RARP (Reverse Address Resolution Protocol) and IGMP (Internet Group Management Protocol).

    Layer 1. Network Access Layer
    Network Access Layer is the first layer of the four layer TCP/IP model. Network Access Layer defines details of how data is physically sent through the network, including how bits are electrically or optically signaled by hardware devices that interface directly with a network medium, such as coaxial cable, optical fiber, or twisted pair copper wire.

    The protocols included in Network Access Layer are Ethernet, Token Ring, FDDI, X.25, Frame Relay etc.

    The most popular LAN architecture among those listed above is Ethernet. Ethernet uses an Access Method called CSMA/CD (Carrier Sense Multiple Access/Collision Detection) to access the media, when Ethernet operates in a shared media. An Access Method determines how a host will place data on the medium.

    IN CSMA/CD Access Method, every host has equal access to the medium and can place data on the wire when the wire is free from network traffic. When a host wants to place data on the wire, it will check the wire to find whether another host is already using the medium. If there is traffic already in the medium, the host will wait and if there is no traffic, it will place the data in the medium. But, if two systems place data on the medium at the same instance, they will collide with each other, destroying the data. If the data is destroyed during transmission, the data will need to be retransmitted. After collision, each host will wait for a small interval of time and again the data will be retransmitted.

    Protocol Data Unit (PDU):

    CISA Certified Information Systems Auditor Part 68 Q10 166
    CISA Certified Information Systems Auditor Part 68 Q10 166

     

    The following answers are incorrect:

    The other options correctly describe about network device functioning based on TCP/IP model

    Reference:
    CISA review manual 2014 page number 272

  11. Which of the following protocol does NOT work at Network interface layer in TCP/IP model?

    • ICMP
    • DNS
    • ARP
    • Internet protocol
    Explanation:

    The NOT is the keyword used in the question. You need to find out a protocol which does not work at network interface layer in TCP/IP model. DNS protocol works at application layer of a TCP/IP model.

    For your exam you should know below information about TCP/IP model:

    Network models

    CISA Certified Information Systems Auditor Part 68 Q11 167
    CISA Certified Information Systems Auditor Part 68 Q11 167

    Layer 4. Application Layer
    Application layer is the top most layer of four layer TCP/IP model. Application layer is present on the top of the Transport layer. Application layer defines TCP/IP application protocols and how host programs interface with Transport layer services to use the network.

    Application layer includes all the higher-level protocols like DNS (Domain Naming System), HTTP (Hypertext Transfer Protocol), Telnet, SSH, FTP (File Transfer Protocol), TFTP (Trivial File Transfer Protocol), SNMP (Simple Network Management Protocol), SMTP (Simple Mail Transfer Protocol) , DHCP (Dynamic Host Configuration Protocol), X Windows, RDP (Remote Desktop Protocol) etc.

    Layer 3. Transport Layer
    Transport Layer is the third layer of the four layer TCP/IP model. The position of the Transport layer is between Application layer and Internet layer. The purpose of Transport layer is to permit devices on the source and destination hosts to carry on a conversation. Transport layer defines the level of service and status of the connection used when transporting data.

    The main protocols included at Transport layer are TCP (Transmission Control Protocol) and UDP (User Datagram Protocol).

    Layer 2. Internet Layer
    Internet Layer is the second layer of the four layer TCP/IP model. The position of Internet layer is between Network Access Layer and Transport layer. Internet layer pack data into data packets known as IP datagram’s, which contain source and destination address (logical address or IP address) information that is used to forward the datagram’s between hosts and across networks. The Internet layer is also responsible for routing of IP datagram’s.

    Packet switching network depends upon a connectionless internetwork layer. This layer is known as Internet layer. Its job is to allow hosts to insert packets into any network and have them to deliver independently to the destination. At the destination side data packets may appear in a different order than they were sent. It is the job of the higher layers to rearrange them in order to deliver them to proper network applications operating at the Application layer.

    The main protocols included at Internet layer are IP (Internet Protocol), ICMP (Internet Control Message Protocol), ARP (Address Resolution Protocol), RARP (Reverse Address Resolution Protocol) and IGMP (Internet Group Management Protocol).

    Layer 1. Network Access Layer
    Network Access Layer is the first layer of the four layer TCP/IP model. Network Access Layer defines details of how data is physically sent through the network, including how bits are electrically or optically signaled by hardware devices that interface directly with a network medium, such as coaxial cable, optical fiber, or twisted pair copper wire.

    The protocols included in Network Access Layer are Ethernet, Token Ring, FDDI, X.25, Frame Relay etc.

    The most popular LAN architecture among those listed above is Ethernet. Ethernet uses an Access Method called CSMA/CD (Carrier Sense Multiple Access/Collision Detection) to access the media, when Ethernet operates in a shared media. An Access Method determines how a host will place data on the medium.

    IN CSMA/CD Access Method, every host has equal access to the medium and can place data on the wire when the wire is free from network traffic. When a host wants to place data on the wire, it will check the wire to find whether another host is already using the medium. If there is traffic already in the medium, the host will wait and if there is no traffic, it will place the data in the medium. But, if two systems place data on the medium at the same instance, they will collide with each other, destroying the data. If the data is destroyed during transmission, the data will need to be retransmitted. After collision, each host will wait for a small interval of time and again the data will be retransmitted.

    Protocol Data Unit (PDU):

    CISA Certified Information Systems Auditor Part 68 Q11 168
    CISA Certified Information Systems Auditor Part 68 Q11 168

    The following answers are incorrect:

    ICMP, ARP and Internet protocol works at Network interface layer of a TCP/IP model.

    Reference:
    CISA review manual 2014 page number 272

  12. Which of the following is the protocol data unit (PDU) of application layer in TCP/IP model?

    • Data
    • Segment
    • Packet
    • Frame
    Explanation:

    Application layer’s PDU is data.

    For your exam you should know below information about TCP/IP model:
    Network models

    CISA Certified Information Systems Auditor Part 68 Q12 169
    CISA Certified Information Systems Auditor Part 68 Q12 169

    Layer 4. Application Layer
    Application layer is the top most layer of four layer TCP/IP model. Application layer is present on the top of the Transport layer. Application layer defines TCP/IP application protocols and how host programs interface with Transport layer services to use the network.

    Application layer includes all the higher-level protocols like DNS (Domain Naming System), HTTP (Hypertext Transfer Protocol), Telnet, SSH, FTP (File Transfer Protocol), TFTP (Trivial File Transfer Protocol), SNMP (Simple Network Management Protocol), SMTP (Simple Mail Transfer Protocol) , DHCP (Dynamic Host Configuration Protocol), X Windows, RDP (Remote Desktop Protocol) etc.

    Layer 3. Transport Layer
    Transport Layer is the third layer of the four layer TCP/IP model. The position of the Transport layer is between Application layer and Internet layer. The purpose of Transport layer is to permit devices on the source and destination hosts to carry on a conversation. Transport layer defines the level of service and status of the connection used when transporting data.

    The main protocols included at Transport layer are TCP (Transmission Control Protocol) and UDP (User Datagram Protocol).

    Layer 2. Internet Layer
    Internet Layer is the second layer of the four layer TCP/IP model. The position of Internet layer is between Network Access Layer and Transport layer. Internet layer pack data into data packets known as IP datagram’s, which contain source and destination address (logical address or IP address) information that is used to forward the datagram’s between hosts and across networks. The Internet layer is also responsible for routing of IP datagram’s.

    Packet switching network depends upon a connectionless internetwork layer. This layer is known as Internet layer. Its job is to allow hosts to insert packets into any network and have them to deliver independently to the destination. At the destination side data packets may appear in a different order than they were sent. It is the job of the higher layers to rearrange them in order to deliver them to proper network applications operating at the Application layer.

    The main protocols included at Internet layer are IP (Internet Protocol), ICMP (Internet Control Message Protocol), ARP (Address Resolution Protocol), RARP (Reverse Address Resolution Protocol) and IGMP (Internet Group Management Protocol).

    Layer 1. Network Access Layer
    Network Access Layer is the first layer of the four layer TCP/IP model. Network Access Layer defines details of how data is physically sent through the network, including how bits are electrically or optically signaled by hardware devices that interface directly with a network medium, such as coaxial cable, optical fiber, or twisted pair copper wire.

    The protocols included in Network Access Layer are Ethernet, Token Ring, FDDI, X.25, Frame Relay etc.

    The most popular LAN architecture among those listed above is Ethernet. Ethernet uses an Access Method called CSMA/CD (Carrier Sense Multiple Access/Collision Detection) to access the media, when Ethernet operates in a shared media. An Access Method determines how a host will place data on the medium.

    IN CSMA/CD Access Method, every host has equal access to the medium and can place data on the wire when the wire is free from network traffic. When a host wants to place data on the wire, it will check the wire to find whether another host is already using the medium. If there is traffic already in the medium, the host will wait and if there is no traffic, it will place the data in the medium. But, if two systems place data on the medium at the same instance, they will collide with each other, destroying the data. If the data is destroyed during transmission, the data will need to be retransmitted. After collision, each host will wait for a small interval of time and again the data will be retransmitted.

    Protocol Data Unit (PDU):

    CISA Certified Information Systems Auditor Part 68 Q12 170
    CISA Certified Information Systems Auditor Part 68 Q12 170

    The following answers are incorrect:

    Segment – Transport layer PDU
    Packet – Network interface layer PDU
    Frame/bit – LAN or WAN interface layer PDU

    Reference:
    CISA review manual 2014 page number 272

  13. Which of the following is protocol data unit (PDU) of transport layer in TCP/IP model?

    • Data
    • Segment
    • Packet
    • Frame
    Explanation:

    For your exam you should know below information about TCP/IP model:

    Network models

    CISA Certified Information Systems Auditor Part 68 Q13 171
    CISA Certified Information Systems Auditor Part 68 Q13 171

    Layer 4. Application Layer
    Application layer is the top most layer of four layer TCP/IP model. Application layer is present on the top of the Transport layer. Application layer defines TCP/IP application protocols and how host programs interface with Transport layer services to use the network.

    Application layer includes all the higher-level protocols like DNS (Domain Naming System), HTTP (Hypertext Transfer Protocol), Telnet, SSH, FTP (File Transfer Protocol), TFTP (Trivial File Transfer Protocol), SNMP (Simple Network Management Protocol), SMTP (Simple Mail Transfer Protocol) , DHCP (Dynamic Host Configuration Protocol), X Windows, RDP (Remote Desktop Protocol) etc.

    Layer 3. Transport Layer
    Transport Layer is the third layer of the four layer TCP/IP model. The position of the Transport layer is between Application layer and Internet layer. The purpose of Transport layer is to permit devices on the source and destination hosts to carry on a conversation. Transport layer defines the level of service and status of the connection used when transporting data.

    The main protocols included at Transport layer are TCP (Transmission Control Protocol) and UDP (User Datagram Protocol).

    Layer 2. Internet Layer
    Internet Layer is the second layer of the four layer TCP/IP model. The position of Internet layer is between Network Access Layer and Transport layer. Internet layer pack data into data packets known as IP datagram’s, which contain source and destination address (logical address or IP address) information that is used to forward the datagram’s between hosts and across networks. The Internet layer is also responsible for routing of IP datagram’s.

    Packet switching network depends upon a connectionless internetwork layer. This layer is known as Internet layer. Its job is to allow hosts to insert packets into any network and have them to deliver independently to the destination. At the destination side data packets may appear in a different order than they were sent. It is the job of the higher layers to rearrange them in order to deliver them to proper network applications operating at the Application layer.

    The main protocols included at Internet layer are IP (Internet Protocol), ICMP (Internet Control Message Protocol), ARP (Address Resolution Protocol), RARP (Reverse Address Resolution Protocol) and IGMP (Internet Group Management Protocol).

    Layer 1. Network Access Layer
    Network Access Layer is the first layer of the four layer TCP/IP model. Network Access Layer defines details of how data is physically sent through the network, including how bits are electrically or optically signaled by hardware devices that interface directly with a network medium, such as coaxial cable, optical fiber, or twisted pair copper wire.

    The protocols included in Network Access Layer are Ethernet, Token Ring, FDDI, X.25, Frame Relay etc.

    The most popular LAN architecture among those listed above is Ethernet. Ethernet uses an Access Method called CSMA/CD (Carrier Sense Multiple Access/Collision Detection) to access the media, when Ethernet operates in a shared media. An Access Method determines how a host will place data on the medium.

    IN CSMA/CD Access Method, every host has equal access to the medium and can place data on the wire when the wire is free from network traffic. When a host wants to place data on the wire, it will check the wire to find whether another host is already using the medium. If there is traffic already in the medium, the host will wait and if there is no traffic, it will place the data in the medium. But, if two systems place data on the medium at the same instance, they will collide with each other, destroying the data. If the data is destroyed during transmission, the data will need to be retransmitted. After collision, each host will wait for a small interval of time and again the data will be retransmitted.

    Protocol Data Unit (PDU):

    CISA Certified Information Systems Auditor Part 68 Q13 172
    CISA Certified Information Systems Auditor Part 68 Q13 172

    The following answers are incorrect:

    Data – Application layer PDU
    Packet – Network interface layer PDU
    Frame/bit – LAN or WAN interface layer PDU

    Reference:
    CISA review manual 2014 page number 272

  14. Which of the following is protocol data unit (PDU) of network interface layer in TCP/IP model?

    • Data
    • Segment
    • Packet
    • Frame
    Explanation:

    For your exam you should know below information about TCP/IP model:
    Network models

    CISA Certified Information Systems Auditor Part 68 Q14 173
    CISA Certified Information Systems Auditor Part 68 Q14 173

    Layer 4. Application Layer
    Application layer is the top most layer of four layer TCP/IP model. Application layer is present on the top of the Transport layer. Application layer defines TCP/IP application protocols and how host programs interface with Transport layer services to use the network.

    Application layer includes all the higher-level protocols like DNS (Domain Naming System), HTTP (Hypertext Transfer Protocol), Telnet, SSH, FTP (File Transfer Protocol), TFTP (Trivial File Transfer Protocol), SNMP (Simple Network Management Protocol), SMTP (Simple Mail Transfer Protocol) , DHCP (Dynamic Host Configuration Protocol), X Windows, RDP (Remote Desktop Protocol) etc.

    Layer 3. Transport Layer
    Transport Layer is the third layer of the four layer TCP/IP model. The position of the Transport layer is between Application layer and Internet layer. The purpose of Transport layer is to permit devices on the source and destination hosts to carry on a conversation. Transport layer defines the level of service and status of the connection used when transporting data.

    The main protocols included at Transport layer are TCP (Transmission Control Protocol) and UDP (User Datagram Protocol).

    Layer 2. Internet Layer
    Internet Layer is the second layer of the four layer TCP/IP model. The position of Internet layer is between Network Access Layer and Transport layer. Internet layer pack data into data packets known as IP datagram’s, which contain source and destination address (logical address or IP address) information that is used to forward the datagram’s between hosts and across networks. The Internet layer is also responsible for routing of IP datagram’s.

    Packet switching network depends upon a connectionless internetwork layer. This layer is known as Internet layer. Its job is to allow hosts to insert packets into any network and have them to deliver independently to the destination. At the destination side data packets may appear in a different order than they were sent. It is the job of the higher layers to rearrange them in order to deliver them to proper network applications operating at the Application layer.

    The main protocols included at Internet layer are IP (Internet Protocol), ICMP (Internet Control Message Protocol), ARP (Address Resolution Protocol), RARP (Reverse Address Resolution Protocol) and IGMP (Internet Group Management Protocol).

    Layer 1. Network Access Layer
    Network Access Layer is the first layer of the four layer TCP/IP model. Network Access Layer defines details of how data is physically sent through the network, including how bits are electrically or optically signaled by hardware devices that interface directly with a network medium, such as coaxial cable, optical fiber, or twisted pair copper wire.

    The protocols included in Network Access Layer are Ethernet, Token Ring, FDDI, X.25, Frame Relay etc.

    The most popular LAN architecture among those listed above is Ethernet. Ethernet uses an Access Method called CSMA/CD (Carrier Sense Multiple Access/Collision Detection) to access the media, when Ethernet operates in a shared media. An Access Method determines how a host will place data on the medium.

    IN CSMA/CD Access Method, every host has equal access to the medium and can place data on the wire when the wire is free from network traffic. When a host wants to place data on the wire, it will check the wire to find whether another host is already using the medium. If there is traffic already in the medium, the host will wait and if there is no traffic, it will place the data in the medium. But, if two systems place data on the medium at the same instance, they will collide with each other, destroying the data. If the data is destroyed during transmission, the data will need to be retransmitted. After collision, each host will wait for a small interval of time and again the data will be retransmitted.

    Protocol Data Unit (PDU):

    CISA Certified Information Systems Auditor Part 68 Q14 174
    CISA Certified Information Systems Auditor Part 68 Q14 174

    The following answers are incorrect:

    Data – Application layer PDU
    Segment – Transport layer PDU
    Frame/bit – LAN or WAN interface layer PDU

    Reference:
    CISA review manual 2014 page number 272

  15. Which of the following is protocol data unit (PDU) of data at LAN or WAN interface layer in TCP/IP model?

    • Data
    • Segment
    • Packet
    • Frame and bits
    Explanation:

    For your exam you should know below information about TCP/IP model:
    Network Models

    CISA Certified Information Systems Auditor Part 68 Q15 175
    CISA Certified Information Systems Auditor Part 68 Q15 175

    Layer 4. Application Layer
    Application layer is the top most layer of four layer TCP/IP model. Application layer is present on the top of the Transport layer. Application layer defines TCP/IP application protocols and how host programs interface with Transport layer services to use the network.

    Application layer includes all the higher-level protocols like DNS (Domain Naming System), HTTP (Hypertext Transfer Protocol), Telnet, SSH, FTP (File Transfer Protocol), TFTP (Trivial File Transfer Protocol), SNMP (Simple Network Management Protocol), SMTP (Simple Mail Transfer Protocol) , DHCP (Dynamic Host Configuration Protocol), X Windows, RDP (Remote Desktop Protocol) etc.

    Layer 3. Transport Layer
    Transport Layer is the third layer of the four layer TCP/IP model. The position of the Transport layer is between Application layer and Internet layer. The purpose of Transport layer is to permit devices on the source and destination hosts to carry on a conversation. Transport layer defines the level of service and status of the connection used when transporting data.

    The main protocols included at Transport layer are TCP (Transmission Control Protocol) and UDP (User Datagram Protocol).

    Layer 2. Internet Layer
    Internet Layer is the second layer of the four layer TCP/IP model. The position of Internet layer is between Network Access Layer and Transport layer. Internet layer pack data into data packets known as IP datagram’s, which contain source and destination address (logical address or IP address) information that is used to forward the datagram’s between hosts and across networks. The Internet layer is also responsible for routing of IP datagram’s.

    Packet switching network depends upon a connectionless internetwork layer. This layer is known as Internet layer. Its job is to allow hosts to insert packets into any network and have them to deliver independently to the destination. At the destination side data packets may appear in a different order than they were sent. It is the job of the higher layers to rearrange them in order to deliver them to proper network applications operating at the Application layer.

    The main protocols included at Internet layer are IP (Internet Protocol), ICMP (Internet Control Message Protocol), ARP (Address Resolution Protocol), RARP (Reverse Address Resolution Protocol) and IGMP (Internet Group Management Protocol).

    Layer 1. Network Access Layer
    Network Access Layer is the first layer of the four layer TCP/IP model. Network Access Layer defines details of how data is physically sent through the network, including how bits are electrically or optically signaled by hardware devices that interface directly with a network medium, such as coaxial cable, optical fiber, or twisted pair copper wire.

    The protocols included in Network Access Layer are Ethernet, Token Ring, FDDI, X.25, Frame Relay etc.

    The most popular LAN architecture among those listed above is Ethernet. Ethernet uses an Access Method called CSMA/CD (Carrier Sense Multiple Access/Collision Detection) to access the media, when Ethernet operates in a shared media. An Access Method determines how a host will place data on the medium.

    IN CSMA/CD Access Method, every host has equal access to the medium and can place data on the wire when the wire is free from network traffic. When a host wants to place data on the wire, it will check the wire to find whether another host is already using the medium. If there is traffic already in the medium, the host will wait and if there is no traffic, it will place the data in the medium. But, if two systems place data on the medium at the same instance, they will collide with each other, destroying the data. If the data is destroyed during transmission, the data will need to be retransmitted. After collision, each host will wait for a small interval of time and again the data will be retransmitted.

    Protocol Data Unit (PDU):

    CISA Certified Information Systems Auditor Part 68 Q15 176
    CISA Certified Information Systems Auditor Part 68 Q15 176

    The following answers are incorrect:

    Data – Application layer data PDU
    Segment – Transport layer data PDU
    Packet – Network interface layer data PDU

    Reference:
    CISA review manual 2014 page number 272

  16. Which of the following INCORRECTLY describes the layer function of the Application Layer within the TCP/IP model?

    • Provides user interface
    • Perform data processing such as encryption, encoding, etc
    • Provides reliable delivery
    • Keeps separate the data of different applications
    Explanation:

    The word INCORRECTLY keyword is used in the question.

    You need to find out the service or functionality which is not performed by application layer of a TCP/IP model.

    The reliable or unreliable delivery of a message is the functionality of transport layer of a TCP/IP model.

    For your exam you should know below information about TCP/IP model:
    Network Models

    CISA Certified Information Systems Auditor Part 68 Q16 177
    CISA Certified Information Systems Auditor Part 68 Q16 177

    Layer 4. Application Layer
    Application layer is the top most layer of four layer TCP/IP model. Application layer is present on the top of the Transport layer. Application layer defines TCP/IP application protocols and how host programs interface with Transport layer services to use the network.

    Application layer includes all the higher-level protocols like DNS (Domain Naming System), HTTP (Hypertext Transfer Protocol), Telnet, SSH, FTP (File Transfer Protocol), TFTP (Trivial File Transfer Protocol), SNMP (Simple Network Management Protocol), SMTP (Simple Mail Transfer Protocol) , DHCP (Dynamic Host Configuration Protocol), X Windows, RDP (Remote Desktop Protocol) etc.

    Layer 3. Transport Layer
    Transport Layer is the third layer of the four layer TCP/IP model. The position of the Transport layer is between Application layer and Internet layer. The purpose of Transport layer is to permit devices on the source and destination hosts to carry on a conversation. Transport layer defines the level of service and status of the connection used when transporting data.

    The main protocols included at Transport layer are TCP (Transmission Control Protocol) and UDP (User Datagram Protocol).

    Layer 2. Internet Layer
    Internet Layer is the second layer of the four layer TCP/IP model. The position of Internet layer is between Network Access Layer and Transport layer. Internet layer pack data into data packets known as IP datagram’s, which contain source and destination address (logical address or IP address) information that is used to forward the datagram’s between hosts and across networks. The Internet layer is also responsible for routing of IP datagram’s.

    Packet switching network depends upon a connectionless internetwork layer. This layer is known as Internet layer. Its job is to allow hosts to insert packets into any network and have them to deliver independently to the destination. At the destination side data packets may appear in a different order than they were sent. It is the job of the higher layers to rearrange them in order to deliver them to proper network applications operating at the Application layer.

    The main protocols included at Internet layer are IP (Internet Protocol), ICMP (Internet Control Message Protocol), ARP (Address Resolution Protocol), RARP (Reverse Address Resolution Protocol) and IGMP (Internet Group Management Protocol).

    Layer 1. Network Access Layer
    Network Access Layer is the first layer of the four layer TCP/IP model. Network Access Layer defines details of how data is physically sent through the network, including how bits are electrically or optically signaled by hardware devices that interface directly with a network medium, such as coaxial cable, optical fiber, or twisted pair copper wire.

    The protocols included in Network Access Layer are Ethernet, Token Ring, FDDI, X.25, Frame Relay etc.

    The most popular LAN architecture among those listed above is Ethernet. Ethernet uses an Access Method called CSMA/CD (Carrier Sense Multiple Access/Collision Detection) to access the media, when Ethernet operates in a shared media. An Access Method determines how a host will place data on the medium.

    IN CSMA/CD Access Method, every host has equal access to the medium and can place data on the wire when the wire is free from network traffic. When a host wants to place data on the wire, it will check the wire to find whether another host is already using the medium. If there is traffic already in the medium, the host will wait and if there is no traffic, it will place the data in the medium. But, if two systems place data on the medium at the same instance, they will collide with each other, destroying the data. If the data is destroyed during transmission, the data will need to be retransmitted. After collision, each host will wait for a small interval of time and again the data will be retransmitted.

    Protocol Data Unit (PDU):

    CISA Certified Information Systems Auditor Part 68 Q16 178
    CISA Certified Information Systems Auditor Part 68 Q16 178

    The following answers are incorrect:

    The other options correctly describe functionalities of application layer in TCP/IP model.

    Reference:
    CISA review manual 2014 page number 272

  17. Which of the following INCORRECTLY describes the layer functions of the LAN or WAN Layer of the TCP/IP model?

    • Combines packets into bytes and bytes into frame
    • Providers logical addressing which routers use for path determination
    • Provide address to media using MAC address
    • Performs only error detection
    Explanation:

    The word INCORRECTLY is the keyword used in the question. You need to find out the functionality that is not performed by LAN or WAN layer in TCP/IP model.

    The Network layer of a TCP/IP model provides logical addressing which routers use for path determination.

    For your exam you should know below information about TCP/IP model:
    Network Models

    CISA Certified Information Systems Auditor Part 68 Q17 179
    CISA Certified Information Systems Auditor Part 68 Q17 179

    Layer 4. Application Layer
    Application layer is the top most layer of four layer TCP/IP model. Application layer is present on the top of the Transport layer. Application layer defines TCP/IP application protocols and how host programs interface with Transport layer services to use the network.

    Application layer includes all the higher-level protocols like DNS (Domain Naming System), HTTP (Hypertext Transfer Protocol), Telnet, SSH, FTP (File Transfer Protocol), TFTP (Trivial File Transfer Protocol), SNMP (Simple Network Management Protocol), SMTP (Simple Mail Transfer Protocol) , DHCP (Dynamic Host Configuration Protocol), X Windows, RDP (Remote Desktop Protocol) etc.

    Layer 3. Transport Layer
    Transport Layer is the third layer of the four layer TCP/IP model. The position of the Transport layer is between Application layer and Internet layer. The purpose of Transport layer is to permit devices on the source and destination hosts to carry on a conversation. Transport layer defines the level of service and status of the connection used when transporting data.

    The main protocols included at Transport layer are TCP (Transmission Control Protocol) and UDP (User Datagram Protocol).

    Layer 2. Internet Layer
    Internet Layer is the second layer of the four layer TCP/IP model. The position of Internet layer is between Network Access Layer and Transport layer. Internet layer pack data into data packets known as IP datagram’s, which contain source and destination address (logical address or IP address) information that is used to forward the datagram’s between hosts and across networks. The Internet layer is also responsible for routing of IP datagram’s.

    Packet switching network depends upon a connectionless internetwork layer. This layer is known as Internet layer. Its job is to allow hosts to insert packets into any network and have them to deliver independently to the destination. At the destination side data packets may appear in a different order than they were sent. It is the job of the higher layers to rearrange them in order to deliver them to proper network applications operating at the Application layer.

    The main protocols included at Internet layer are IP (Internet Protocol), ICMP (Internet Control Message Protocol), ARP (Address Resolution Protocol), RARP (Reverse Address Resolution Protocol) and IGMP (Internet Group Management Protocol).

    Layer 1. Network Access Layer
    Network Access Layer is the first layer of the four layer TCP/IP model. Network Access Layer defines details of how data is physically sent through the network, including how bits are electrically or optically signaled by hardware devices that interface directly with a network medium, such as coaxial cable, optical fiber, or twisted pair copper wire.

    The protocols included in Network Access Layer are Ethernet, Token Ring, FDDI, X.25, Frame Relay etc.

    The most popular LAN architecture among those listed above is Ethernet. Ethernet uses an Access Method called CSMA/CD (Carrier Sense Multiple Access/Collision Detection) to access the media, when Ethernet operates in a shared media. An Access Method determines how a host will place data on the medium.

    IN CSMA/CD Access Method, every host has equal access to the medium and can place data on the wire when the wire is free from network traffic. When a host wants to place data on the wire, it will check the wire to find whether another host is already using the medium. If there is traffic already in the medium, the host will wait and if there is no traffic, it will place the data in the medium. But, if two systems place data on the medium at the same instance, they will collide with each other, destroying the data. If the data is destroyed during transmission, the data will need to be retransmitted. After collision, each host will wait for a small interval of time and again the data will be retransmitted.

    Protocol Data Unit (PDU):

    CISA Certified Information Systems Auditor Part 68 Q17 180
    CISA Certified Information Systems Auditor Part 68 Q17 180

    The following answers are incorrect:

    The other options correctly describe functionalities of application layer in TCP/IP model.

    Reference:
    CISA review manual 2014 page number 272

  18. Which of the following functionality is NOT performed by the application layer of a TCP/IP model?

    • Print service, application services
    • Data encryption and compression
    • Dialog management
    • End-to-end connection
    Explanation:

    The word NOT is the keyword used in the question. You need to find out a functionality which is not performed by application layer of a TCP/IP model.

    End-to-end connection is the Transport layer functionality in TCP/IP model.

    For your exam you should know below information about TCP/IP model:
    Network Models

    CISA Certified Information Systems Auditor Part 68 Q18 181
    CISA Certified Information Systems Auditor Part 68 Q18 181

    Layer 4. Application Layer
    Application layer is the top most layer of four layer TCP/IP model. Application layer is present on the top of the Transport layer. Application layer defines TCP/IP application protocols and how host programs interface with Transport layer services to use the network.

    Application layer includes all the higher-level protocols like DNS (Domain Naming System), HTTP (Hypertext Transfer Protocol), Telnet, SSH, FTP (File Transfer Protocol), TFTP (Trivial File Transfer Protocol), SNMP (Simple Network Management Protocol), SMTP (Simple Mail Transfer Protocol) , DHCP (Dynamic Host Configuration Protocol), X Windows, RDP (Remote Desktop Protocol) etc.

    Layer 3. Transport Layer
    Transport Layer is the third layer of the four layer TCP/IP model. The position of the Transport layer is between Application layer and Internet layer. The purpose of Transport layer is to permit devices on the source and destination hosts to carry on a conversation. Transport layer defines the level of service and status of the connection used when transporting data.

    The main protocols included at Transport layer are TCP (Transmission Control Protocol) and UDP (User Datagram Protocol).

    Layer 2. Internet Layer
    Internet Layer is the second layer of the four layer TCP/IP model. The position of Internet layer is between Network Access Layer and Transport layer. Internet layer pack data into data packets known as IP datagram’s, which contain source and destination address (logical address or IP address) information that is used to forward the datagram’s between hosts and across networks. The Internet layer is also responsible for routing of IP datagram’s.

    Packet switching network depends upon a connectionless internetwork layer. This layer is known as Internet layer. Its job is to allow hosts to insert packets into any network and have them to deliver independently to the destination. At the destination side data packets may appear in a different order than they were sent. It is the job of the higher layers to rearrange them in order to deliver them to proper network applications operating at the Application layer.

    The main protocols included at Internet layer are IP (Internet Protocol), ICMP (Internet Control Message Protocol), ARP (Address Resolution Protocol), RARP (Reverse Address Resolution Protocol) and IGMP (Internet Group Management Protocol).

    Layer 1. Network Access Layer
    Network Access Layer is the first layer of the four layer TCP/IP model. Network Access Layer defines details of how data is physically sent through the network, including how bits are electrically or optically signaled by hardware devices that interface directly with a network medium, such as coaxial cable, optical fiber, or twisted pair copper wire.

    The protocols included in Network Access Layer are Ethernet, Token Ring, FDDI, X.25, Frame Relay etc.

    The most popular LAN architecture among those listed above is Ethernet. Ethernet uses an Access Method called CSMA/CD (Carrier Sense Multiple Access/Collision Detection) to access the media, when Ethernet operates in a shared media. An Access Method determines how a host will place data on the medium.

    IN CSMA/CD Access Method, every host has equal access to the medium and can place data on the wire when the wire is free from network traffic. When a host wants to place data on the wire, it will check the wire to find whether another host is already using the medium. If there is traffic already in the medium, the host will wait and if there is no traffic, it will place the data in the medium. But, if two systems place data on the medium at the same instance, they will collide with each other, destroying the data. If the data is destroyed during transmission, the data will need to be retransmitted. After collision, each host will wait for a small interval of time and again the data will be retransmitted.

    Protocol Data Unit (PDU):

    CISA Certified Information Systems Auditor Part 68 Q18 182
    CISA Certified Information Systems Auditor Part 68 Q18 182

    The following answers are incorrect:

    The other functionalities described in the options are performed by application layer in TCP/IP model.

    Reference:
    CISA review manual 2014 page number 272

  19. Which of the following is the INCORRECT “layer – protocol” mapping within the TCP/IP model?

    • Application layer – NFS
    • Transport layer – TCP
    • Network layer – UDP
    • LAN or WAN interface layer – point-to-point protocol
    Explanation:

    The word INCORRECT is the keyword used in the question.

    You need to find out invalid layer-protocol mapping.

    The UDP protocol works at Transport layer of a TCP/IP model.

    For your exam you should know below information about TCP/IP model:
    Network Models

    CISA Certified Information Systems Auditor Part 68 Q19 183
    CISA Certified Information Systems Auditor Part 68 Q19 183

    Layer 4. Application Layer
    Application layer is the top most layer of four layer TCP/IP model. Application layer is present on the top of the Transport layer. Application layer defines TCP/IP application protocols and how host programs interface with Transport layer services to use the network.

    Application layer includes all the higher-level protocols like DNS (Domain Naming System), HTTP (Hypertext Transfer Protocol), Telnet, SSH, FTP (File Transfer Protocol), TFTP (Trivial File Transfer Protocol), SNMP (Simple Network Management Protocol), SMTP (Simple Mail Transfer Protocol) , DHCP (Dynamic Host Configuration Protocol), X Windows, RDP (Remote Desktop Protocol) etc.

    Layer 3. Transport Layer
    Transport Layer is the third layer of the four layer TCP/IP model. The position of the Transport layer is between Application layer and Internet layer. The purpose of Transport layer is to permit devices on the source and destination hosts to carry on a conversation. Transport layer defines the level of service and status of the connection used when transporting data.

    The main protocols included at Transport layer are TCP (Transmission Control Protocol) and UDP (User Datagram Protocol).

    Layer 2. Internet Layer
    Internet Layer is the second layer of the four layer TCP/IP model. The position of Internet layer is between Network Access Layer and Transport layer. Internet layer pack data into data packets known as IP datagram’s, which contain source and destination address (logical address or IP address) information that is used to forward the datagram’s between hosts and across networks. The Internet layer is also responsible for routing of IP datagram’s.

    Packet switching network depends upon a connectionless internetwork layer. This layer is known as Internet layer. Its job is to allow hosts to insert packets into any network and have them to deliver independently to the destination. At the destination side data packets may appear in a different order than they were sent. It is the job of the higher layers to rearrange them in order to deliver them to proper network applications operating at the Application layer.

    The main protocols included at Internet layer are IP (Internet Protocol), ICMP (Internet Control Message Protocol), ARP (Address Resolution Protocol), RARP (Reverse Address Resolution Protocol) and IGMP (Internet Group Management Protocol).

    Layer 1. Network Access Layer
    Network Access Layer is the first layer of the four layer TCP/IP model. Network Access Layer defines details of how data is physically sent through the network, including how bits are electrically or optically signaled by hardware devices that interface directly with a network medium, such as coaxial cable, optical fiber, or twisted pair copper wire.

    The protocols included in Network Access Layer are Ethernet, Token Ring, FDDI, X.25, Frame Relay etc.

    The most popular LAN architecture among those listed above is Ethernet. Ethernet uses an Access Method called CSMA/CD (Carrier Sense Multiple Access/Collision Detection) to access the media, when Ethernet operates in a shared media. An Access Method determines how a host will place data on the medium.

    IN CSMA/CD Access Method, every host has equal access to the medium and can place data on the wire when the wire is free from network traffic. When a host wants to place data on the wire, it will check the wire to find whether another host is already using the medium. If there is traffic already in the medium, the host will wait and if there is no traffic, it will place the data in the medium. But, if two systems place data on the medium at the same instance, they will collide with each other, destroying the data. If the data is destroyed during transmission, the data will need to be retransmitted. After collision, each host will wait for a small interval of time and again the data will be retransmitted.

    Protocol Data Unit (PDU):

    CISA Certified Information Systems Auditor Part 68 Q19 184
    CISA Certified Information Systems Auditor Part 68 Q19 184

    The following answers are incorrect:

    The other options correctly describe layer-protocol mapping in TCP/IP protocol.

    Reference:
    CISA review manual 2014 page number 272

  20. Which of the following is the INCORRECT “layer – protocol data unit (PDU)” mapping within the TCP/IP model?

    • Application layer – Data
    • Transport layer – Segment
    • Network layer – Frame
    • Physical layer – bits
    Explanation:

    The word INCORRECT is the keyword used in the question. You need to find out incorrect layer-protocol mapping from give options.

    The correct mapping is Network layer – Packet.
    The LAN or WAN interface layer creates frame.

    For your exam you should know below information about TCP/IP model:
    Network Models

    CISA Certified Information Systems Auditor Part 68 Q20 185
    CISA Certified Information Systems Auditor Part 68 Q20 185

    Layer 4. Application Layer
    Application layer is the top most layer of four layer TCP/IP model. Application layer is present on the top of the Transport layer. Application layer defines TCP/IP application protocols and how host programs interface with Transport layer services to use the network.

    Application layer includes all the higher-level protocols like DNS (Domain Naming System), HTTP (Hypertext Transfer Protocol), Telnet, SSH, FTP (File Transfer Protocol), TFTP (Trivial File Transfer Protocol), SNMP (Simple Network Management Protocol), SMTP (Simple Mail Transfer Protocol) , DHCP (Dynamic Host Configuration Protocol), X Windows, RDP (Remote Desktop Protocol) etc.

    Layer 3. Transport Layer
    Transport Layer is the third layer of the four layer TCP/IP model. The position of the Transport layer is between Application layer and Internet layer. The purpose of Transport layer is to permit devices on the source and destination hosts to carry on a conversation. Transport layer defines the level of service and status of the connection used when transporting data.

    The main protocols included at Transport layer are TCP (Transmission Control Protocol) and UDP (User Datagram Protocol).

    Layer 2. Internet Layer
    Internet Layer is the second layer of the four layer TCP/IP model. The position of Internet layer is between Network Access Layer and Transport layer. Internet layer pack data into data packets known as IP datagram’s, which contain source and destination address (logical address or IP address) information that is used to forward the datagram’s between hosts and across networks. The Internet layer is also responsible for routing of IP datagram’s.

    Packet switching network depends upon a connectionless internetwork layer. This layer is known as Internet layer. Its job is to allow hosts to insert packets into any network and have them to deliver independently to the destination. At the destination side data packets may appear in a different order than they were sent. It is the job of the higher layers to rearrange them in order to deliver them to proper network applications operating at the Application layer.

    The main protocols included at Internet layer are IP (Internet Protocol), ICMP (Internet Control Message Protocol), ARP (Address Resolution Protocol), RARP (Reverse Address Resolution Protocol) and IGMP (Internet Group Management Protocol).

    Layer 1. Network Access Layer
    Network Access Layer is the first layer of the four layer TCP/IP model. Network Access Layer defines details of how data is physically sent through the network, including how bits are electrically or optically signaled by hardware devices that interface directly with a network medium, such as coaxial cable, optical fiber, or twisted pair copper wire.

    The protocols included in Network Access Layer are Ethernet, Token Ring, FDDI, X.25, Frame Relay etc.

    The most popular LAN architecture among those listed above is Ethernet. Ethernet uses an Access Method called CSMA/CD (Carrier Sense Multiple Access/Collision Detection) to access the media, when Ethernet operates in a shared media. An Access Method determines how a host will place data on the medium.

    IN CSMA/CD Access Method, every host has equal access to the medium and can place data on the wire when the wire is free from network traffic. When a host wants to place data on the wire, it will check the wire to find whether another host is already using the medium. If there is traffic already in the medium, the host will wait and if there is no traffic, it will place the data in the medium. But, if two systems place data on the medium at the same instance, they will collide with each other, destroying the data. If the data is destroyed during transmission, the data will need to be retransmitted. After collision, each host will wait for a small interval of time and again the data will be retransmitted.

    Protocol Data Unit (PDU):

    CISA Certified Information Systems Auditor Part 68 Q20 186
    CISA Certified Information Systems Auditor Part 68 Q20 186

    The following answers are incorrect:

    The other options correctly describe layer-PDU mapping in TCP/IP protocol.

    Reference:
    CISA review manual 2014 page number 272