CompTIA Network+ Certification Study Guide part 66 ppsx

Table A.1 Listing of 802 IEEE Standards Standard Subject\description 802 Standard for Local Area Networks for Computer Interconnection.. Appendix A 643Table A.1 Listing of 802 IEEE Stand

ChApTEr 12 : Network Troubleshooting Methodology

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You are the administrator of the network shown in Figure 12.15

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The user of Computer1 is unable to access a shared resource located on Computer3 Computer1 is able to access shared resources on other subnets on the internal network as well as the Internet Computer3 is able to access shared resources on Computer5 and Computer7, as well as resources on the Internet When you ping Computer1 from Computer3, you receive a “Request Timed Out” message Based on this information, what is the most likely cause of the connectivity issue?

A The router interface attached to Subnet D is malfunctioning

B The router interface attached to Subnet C is malfunctioning

C Router B does not have a route from Subnet C to the Internet

D Router B does not have a route from Subnet C to Subnet D

FIGurE 12.15 Sample network architecture.

Self Test Quick Answer Key 637

A user connected to Subnet B is able to use the resources housed on

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a machine named Server A which is located on Subnet W without

trouble When the same user is working from a d ifferent location,

their machine obtains an IP address from DHCP on Subnet D

and they are no longer able to connect to Server A You have been

attempting to determine the problem So far you have utilized the

ipconfig tool to verify the IP configuration of both the server and

the client, and both appear correct Which of the following

trouble-shooting steps would be a logical next choice? Choose all that apply

A From the user workstation on Subnet D, ping the default gateway

B From Server A, ping the default gateway

C From the user workstation, ping another machine on the same

subnet as Server A

D From the user workstation, ping the loopback address

Your e-mail server is having network connectivity problems You

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have replaced the NIC and reconfigured the IP address The last

step that you take is to start the e-mail services and all services

have now started successfully without generating error messages

Which of the following actions will allow you to verify that the

e-mail services are successfully accepting inbound e-mail?

A Telnet from a client machine to port 25 on the e-mail server

B Telnet from a client machine to port 23 on the e-mail server

C Use POP3 to create an e-mail queue and validate that e-mail

passes through it successfully

D Use IMAP4 to send Internet e-mail to the server

SElF TEST quICK ANSwEr KEy

B

1

C

2

A, D, E, and F

3

B

4

B

5

A and C

6

D

7

A

8

A and B

9

A

10

A and C

11

B

12

D

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A and C

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A

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ThE INSTITuTE oF ElECTrICAl ANd ElECTroNICS

ENGINEErS (IEEE)

IEEE Committee

IEEE is an acronym for the “Institute of Electrical and Electronics Engineers,”

which is an organization that develops and promotes standards dealing with

various technologies These standards serve as the principles and guidelines

for technology While they aren’t government regulations that need to be

followed, they are industry standards that should be followed

While IEEE standards have been used when regulations need to be created,

the importance of the IEEE is really seen outside government regulatory

standards Those who design and manufacture equipment and software look

to these standards so their products can be compliant with IEEE standards

For example, if you bought a digital camera, you would want to be able to

transfer the pictures to your computer Without standards, cameras might

use different cables or ports to transfer this data, meaning that you couldn’t

transfer the data easily to any computer Apple developed FireWire as a

method of connecting devices to computers and transferring large amounts

of data quickly, and IEEE 1394 was developed as a nonproprietary standard

of transferring audio and video Without such standards, your devices would

work with one type of computer (such as a laptop), but not with others (such

as a desktop) By adhering to these standards, products have the ability to be

compatible with other technologies and can operate with other equipment

history and Fundamentals of IEEE

The IEEE was formed in 1963 from a merger of two other organizations: the

American Institute of Electrical Engineers (AIEE) and the Institute of Radio

Engineers (IRE) The AIEE was founded in 1884, as one of a number of

engineer-ing societies at that time It succeeded in developengineer-ing industry and professional

standards for those involved in the electrical and engineering fields As new

technologies emerged, it formed committees to address specialized fields

The Institute of Radio Engineers was founded in 1912, as an amalgamation

of two earlier societies, and focused on obtaining international memberships

Appendix A

Appendix A

640

This organization focused on issues of standardization in radio, not only affecting manufacturing, but also assisted in developing broadcasting regulations and were part of conferences that led to the formation of the Federal Radio Commission in 1927, which later became the Federal Com-munications Commission (FCC) As technologies advanced, the IRE also assisted in standards dealing with FM radio and television

While the IRE started as the smaller organization of the two, it eventually gained a greater membership than the AIEE However, neither organization fully represented all fields associated with electrical or electronic engineering This lead to a merger between the IRE and the AIEE in 1963, and inspired the name change to the Institute of Electrical and Electronic Engineers

Over the years, the IEEE has developed and promoted numerous standards, provided education through publications and journals, and expanded its role in electricity, electronics, and communications to also include computers By creating committees to address emerging technologies and developments in computer engineering and computer science, it has been predominant in providing the standards used in computer hardware, software, and networking

802 Standards

IEEE standards use a numeric naming scheme to identify and group the technologies being addressed Those standards beginning with the number

802 relate to networking, and are developed and evaluated by specialized committees within IEEE The 802 committee was first formed as a

proj-ect in February 1980, and became known as Projproj-ect 802 after the year (80)

and month (2) it was created After more than two decades, it continues to review and provide industry standards for local area networks

The 802 committee is broken down into smaller subcommittees or working groups that focus on specific aspects of networking The various groups that have worked on standards include:

802.1 Higher Layer LAN Protocols

■

■ 802.2 Logical Link Control (LLC) (inactive)

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■ 802.3 Carrier Sense Multiple Access with Collision Detection

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■ (CSMA/CD) – Ethernet 802.4 Token Bus (disbanded)

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■ 802.5 Token Ring (inactive)

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■ 802.6 Metropolitan Area Network (disbanded)

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■

Appendix A 641

802.7 Broadband (disbanded)

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■

802.8 Fiber Optic (disbanded)

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■

802.9 Isochronous LAN (disbanded)

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■

802.10 Security (disbanded)

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■

802.11 Wireless LAN (WLAN)

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■

802.12 Demand Priority (inactive)

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802.14 Cable Modem

■

■

802.15 Wireless Personal Area Network (WPAN)

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802.16 Broadband Wireless Access

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802.17 Resilient Packet Ring

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802.18 Radio Regulatory

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802.19 Coexistence

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802.20 Mobile Broadband Wireless Access (MBWA)

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802.21 Media Independent Handoff

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802.22 Wireless Regional Area Networks

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■

Because technology changes, so do the working groups New working

groups are added to address emerging technologies, while others are

disbanded or become inactive Reasons for disbanding or making a group

inactive varies, but when older technology isn’t used as much or further

standards aren’t required, it makes sense to evaluate the need for a group

An up-to-date list of working groups and their status can be found on the

IEEE Web site at http://grouper.ieee.org/groups/802/dots.html

OSI and 802

The services and protocols specified in the 802 standards correspond to

the lower layers of the OSI model OSI is an acronym for “Open Systems

Interconnect”, and the OSI model is a seven-layer structure that maps to

a logical structure for network operations It is often used to show how

protocols work, and what happens when data is sent over a LAN When

communication is sent over a network, it starts at the topmost layer, and

works its way down to the bottom layers

The bottommost layers of the OSI model are the Data Link and Physical

Layers Earlier, we mentioned how data is broken into smaller pieces before

Appendix A

642

it is sent over a network, which is a primary function of the Data Link Layer When another computer receives these pieces of data, they are reassembled

at the Data Link Layer and passed up to higher layers so they can be further assembled into the data’s original format and be used by an application The 802 standards break the Data Link Layer of the OSI model into two separate subcategories: LLC and Media Access Control (MAC) The LLC is responsible for starting and maintaining connections with devices, while the MAC allows multiple devices to share the media (that is coaxial cable, twisted-pair, and so on) that data is being sent over In other words, when you send data to another computer, it is the LLC that establishes the connection with the other computer, and it is the MAC that allows more than one computer to communicate on the network

The Physical Layer of the OSI model deals with how data moves on and off the network media While it doesn’t specify what media is used, it does identify how it is accessed This includes the topology of the network, electrical and physical aspects of media, and the timing and encoding used for transmitting and receiving bits of data

Table of Standards

IEEE working groups have generated a large number of standards over the years As you can see by these standards, each uses the numeric value of 802

to show it is part of the 802 committee’s networking standards A decimal value is used to designate the working group that developed it, and to show the standard it relates to, while a letter further categorizes specifications, supplements and other addendum While the 802 standards can be seen

in the following table, a full listing of IEEE standards can be found on the organization’s Web site at http://info.computer.org/standards/standesc.htm

Table A.1 Listing of 802 IEEE Standards

Standard Subject\description

802 Standard for Local Area Networks for Computer Interconnection Provides

compatibility between devices that have been made by different manufacturers 802.1 Architecture and Overviews Standard for allowing LAN or MAN to

communicate with another LAN or MAN 802.1b LAN/MAN Management Defines network management architecture and

protocols at OSI layers 1 and 2 802.1d MAC Sublayer Interconnection: MAC Bridges Standard defining

internetworking two or more LANs at the MAC sublayer 802.1e System Load Protocol Standard on loading a LAN station’s local address

space

Appendix A 643

Table A.1 Listing of 802 IEEE Standards continued

Standard Subject\description

802.1f Recommended Practices for the Development of Layer Management

Stan-dards Standard on common management activities across the OSI layers

802.1g MAC Sublayer Interconnection Standard on internetworking two or more

LANs at the MAC sublayer

802.1h LAN: Token Ring Access Method and Physical Layer Specifications

802.1I Standard MAC Bridges: Fiber Distributed Data Interface (FDDI) Supplement

802.1j Managed Objects for MAC Bridges Standard that manages objects for MAC

bridges (corresponds to 802.1d)

802.1k LAN/MAN Management Information for Monitoring and Event Reporting

802.1m System Load Protocol: Managed Object Definition and Protocol

Implementa-tion Conformance Statement (PICS) Proforma Specifies the System Load

Protocol parameters for conformance

802.2 Local Area Networks: LLC Standard on the link layer protocol, which

provides confirmation on the delivery of data over a LAN

802.2a Flow Control Techniques for Bridges – Local Area Networks

802.2b Acknowledged Connectionless-mode Service Type 3 Operation

802.2c Standard for LLC Conformance Requirements

802.2d Supplement to 802.2, Information Processing Systems: LAN Part2: LLC

Provides changes and corrections to the 802.2 standard

802.2e Supplement to 802.2, Information Processing Systems: LAN Part2: Bit

Referencing

802.2f Standard for LLC Sublayer Management Standard on sublayer management

of the LLC

802.2g Supplement to 802.2, LLC Type 4 (High Speed, High Performance)

Operation

802.3 Local Network for Computer Interconnection (CSMA/CD) Standard for

CSMA/CD or Ethernet This provides a standard for communication devices

to be compatible, so there is little to no need for customizing hardware and

software

802.3a Medium Attachment Unit (MAU) and Baseband Medium Specifications for

Type 10Base2 Supplement for 10 Mbps baseband media

802.3b Section 11, Broadband MAU and Broadband Medium Specifications

Supplement to add broadband capabilities to 10 Mbps media

802.3c Local Area Networks: Repeater Unit Defines a standard baseband repeater

for 10BaseX networks, which allows the interconnection of multiple coaxial

segments

802.3d MAU and Baseband Medium Specification for Fiber Optic Inter-Repeater

Unit Specifications for fiber optic interconnections for 10Base5 and 10Base2

networks

Continued

Appendix A

644

Table A.1 Listing of 802 IEEE Standards continued

Standard Subject\description

802.3e Physical Signaling, Medium Attachment and Baseband Medium

Specification, Type 1Base5 Implements a 1 Mbps baseband physical layer for CSMA/CD, using twisted-pair media on a star topology network

802.3h Layer Management Supplement replaces a paragraph in the existing

standard 802.3I MAU and Baseband Medium Specs, Type 10BaseT Specifications for a

MAU and media on a LAN using CSMA/CD, so that it can operate at

10 Mbps on twisted-pair media 802.3j Fiber Optic Active and Passive Star Based 802.3 Segment Supplement for 802.3 802.3k Standard for Repeater Management (revision)

802.3l Supplement to CSMA/CD Access Method and Physical Layer Specifications:

MAU, Type 10BaseT PICS Proforma 802.3m Supplement to CSMA with Collision Detection CSMA/CD Access Method and

Physical Layer Specifications (Second Maintenance Ballot) 802.3n Supplement to CSMA/CD Access with Collision Detection CSMA/CD Access

Method and Physical Layer Specifications (Third Maintenance Ballot) 802.3p CSMA/CD Layer Management for 10 MB/S

802.3q CSMA/CD GDMO Format for Layer Managed Objects 802.3r Supplement to CSMA with CSMA/CD Access Method and Physical Layer

Specifications: Type 10BASE5 MAU PICS 802.3s CSMA/CD Access Method and Physical Layer Specifications: Maintenance

Revision #4 Revisions that provide corrections and updates 802.3t Supplement to CSMA/CD Access Method and Physical Layer Specifications:

Informative Annex for Support of 120 Ohm Cables in 10Base-T Simplex Link Segment

802.3u Supplement to CSMA/CD Access Method and Physical Layer Specifications:

MAC Parameters, Physical Layer, MAUs and Repeater for 100 Mb/s Operation

802.3v Supplement to CSMA/CD Access Method and Physical Layer Specifications:

Informative Annex for Support of 150 Ohm Cables in 10BASE-T Link Segment 802.4 Revision LAN: Token-Bus Access Method

802.4a Fiber Optic Token Bus Specifications for using fiber optic media and adding

an additional physical layer to 802.4 802.4b Redundant Media Control Unit Addendum that deals with connecting

multiple media to a single MAC, and improving physical layer reliability 802.5 LAN: Token Ring Access Method and Physical Layer Specifications 802.5a LAN: Station Management Revision

802.5b LAN: Telephone Twisted Pair Media Specification for using twisted-pair media

in a token ring network

Appendix A 645

Table A.1 Listing of 802 IEEE Standards continued

Standard Subject\description

802.5c LAN: Token Ring Reconfiguration Specification that adds automatic fault

recovery

802.5d LAN: Interconnected Token Ring LANs Specification on multi-ring operations

802.5e LAN: Token Ring Station Management Entity Specifications

802.5f LAN: 16 Mbps Token Ring Operations Specifications for change 4 Mbps

Rings to 16 Mbps

802.5g LAN: Conformance Testing

802.5h LAN: Operation of LLC III on Token Rings

802.5I LAN: Token Ring; Early Token Release

802.5j LAN: Fiber Optic Station Attachment

802.5k Token Ring Media Specification

802.5l Maintenance of Token Ring Standard Revision of token ring access method

and physical layer specifications

802.5m Recommended Practice to Interconnection of Source Routed and

Transparent Bridged Networks

802.5n Unshielded Twisted Pair at 4/16 Mbps Standard for operating 4 Mbps and

16 Mbps Token Ring LANs on unshielded twisted-pair

802.5p LAN: Part 2: LLC; End System Determination

802.5q LAN: Part 5: MAC Revision

802.5r Revision of IEEE Standard 802.5 for Token Ring Station Attachment

802.6 Standard for the Distributed Queue Dual Bus Metropolitan Area Networks

Standard used for Metropolitan Area Networks (MAN), which is used in

specifying the MAC sublayer and physical layer

802.6a Multiple Port Bridging for MAN Standard for services provided by multiple

bridge ports, which are used to connect two or more Dual Bus subnetworks

together

802.6b Standard for Premises Extension of DS3-Based 802.6 MAN

802.6c Standard for DS1 Physical Layer Convergence Procedures

802.6d Standard for SONET (SDH) Based Physical Layer Convergence Procedures

for 802.6 MAN

802.6e Standard for Eraser Node for DQDB MAN

802.6f PICS Proforma

802.6g Standard for Layer Management for the 802.6 MAN

802.6h Standard for Isochronous Services Over the 802.6 MAN

802.6I Standard for Remote LAN Bridging Using the 802.6 MAN Specifies protocols

used between remote LAN bridges

Continued