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CCNA 640-607 Practice Exam Five

Which of the following are true regarding ISDN (Integrated

Services Digital Network)? Choose two.

A. ISDN normally runs by means of a microwave network.

B. ISDN will only permit voice and graphics to be transmitted.

C. ISDN involves the digitization of the telephone network,

which allows source material such as voice, data, video, and

graphics to be transmitted over existing telephone wires.

D. ISDN components include terminal adapters (TA), terminals,

line termination equipment, network termination devices, and

exchange termination equipment.

Answer: C and D

ISDN involves the digitization of the telephone network, which allows

source material such as voice, data, video, and graphics to be

transmitted over existing telephone wires. ISDN components include

terminal adapters (TA), terminals, line termination equipment, network

termination devices, and exchange termination equipment.

What are the two types of ISDN (Integrated Services Digital

Network) terminals? Choose two.

A. TE1

B. SE1

C. SE2

D. TE2

Answer: A and D

TE1 (Terminal Equipment Type 1) are terminals that are ISDN

compliant. TE2 (Terminal Equipment Type 2) are terminals that

predate the ISDN standards and are non-ISDN compliant.

What are the two types of ISDN (Integrated Services Digital

Network) Network Termination devices? Choose two.

A. WT1

B. NT2

C. WT0

D. NT1

Answer: B and D

NT1 (Network Termination Type 1) devices implement ISDN

physical layer functions and connect user devices to the ISDN

facility.

NT2 (Network Termination Type 2) devices perform concentration

services and implement Data Link layer and Network layer

protocol functions.

Which of the following are ISDN (Integrated Services Digital

Network) reference points? Choose four.

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A. W

B. R

C. S

D. T

E. U

F. V

Answer: B, C, D, and E

R is the reference point between non-ISDN equipment and a

Terminal Adapter (TA).

S is the reference point between user terminals and the NT2.

T is the reference point between NT1 and NT2 devices.

U is the reference point between NT1 devices and line terminating

equipment in the carrier network.

The ISDN (Integrated Services Digital Network) BRI (Basic Rate

Interface) consists of which of the following?

A. one B channel and one D channel

B. two B channels and one D channel

C. three B channels and two D channels

D. two D channels and one B channel

Answer: B

The ISDN (Integrated Services Digital Network) BRI (Basic Rate

Interface) consists of two B channels and one D channel. The B

channels operate at 64 Kbps each and the D channel operates at

16 Kbps.

The ISDN (Integrated Services Digital Network) PRI (Primary

Rate Interface) consists of which of the following? Choose two.

A. one B channel and one D channel

B. three B channels and two D channels

C. two D channels and one B channel

D. 23 B channels and one D channel in North America and Japan

E. 30 B channels and one D channel in Europe, Australia, and

other parts of the world.

Answer: D and E

The ISDN (Integrated Services Digital Network) PRI (Primary

Rate Interface) consists of 23 B channels and one D channel in

North America and Japan or 30 B channels and one D channel in

Europe, Australia, and other parts of the world.

What are the three main components of PPP (Point-to-Point

Protocol)?

A. HDLC

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B. PAP

C. LCP

D. NCP

Answer: A, C, and D

The three main components of PPP (Point-to-Point Protocol) are HDLC

(High-Level Data-Link Control), LCP (Link Control Protocol), and NCP

(Network Control Protocol). HDLC is used for encapsulating datagrams

over point-to-point links. LCP establishes, configures, maintains, and

terminates the point-to-point connection. NCP establishes and

configures different network-layer protocols.

Which of the following are true regarding Multilink PPP

(MPPP)? Choose two.

A. Provides frame detection at the Data Link layer

B. Adds support for channel aggregation to PPP

C. Has become a popular replacement for X.25D. Ensures that packets arrive in order at the receiving device

Answer: B and D

Multilink PPP (MPPP) adds support for channel aggregation to

PPP. It ensures that packets arrive in order at the receiving

device.

Which of the following are true regarding Multichassis MPPP?

Choose three.

A. It is a Cisco Systems IOS enhancement to MPPP

B. It helps configure various network protocols

C. It helps track the frequency of network outages

D. It allows WAN administrators to group multiple access

servers into a single stack group

E. It makes use of the Stack Group Bidding Protocol (SGBP)

Answer: A, D, and E

Multichassis MPPP is a Cisco Systems IOS enhancement to MPPP.

It allows channel aggregation across multiple remote-access

servers at a central site. It allows WAN administrators to

group multiple access servers into a single stack group and

makes use of the Stack Group Bidding Protocol (SGBP).

What two types of authentication does PPP support?

A. ISDN

B. PAP

C. NCP

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D. CHAP

Answer: B and D

The two types of authentication that PPP supports are PAP (Password

Authentication Protocol) and CHAP (Challenge Handshake Authentication

Protocol). CHAP is more secure than PAP and is recommended. With PAP, a

users password is sent as clear text. CHAP uses a three-way handshake

protocol.

IBM developed SDLC (Synchronous Data-Link Control) protocol in

the mid-1970s for use in what environment?

A. Token Ring

B. Ethernet

C. ATM

D. SNA

Answer: D

IBM developed SDLC (Synchronous Data-Link Control) protocol in

the mid-1970s for use in SNA (Systems Network Architecture)

environments. It was the first link-layer protocol based on

synchronous, bit-oriented operation.

Which of the following is true regarding SDLC (Synchronous

Data-Link Control)? Choose two.

A. The International Organization for Standardization (ISO)

modified SDLC to create HDLC (High-Level Data-Link Control)

protocol

B. The Institute of Electrical and Electronic Engineers (IEEE)

modified SDLC to create IEEE 802.2

C. SDLC can only be used with multipoint links

D. SDLC remains the primary SNA link-layer protocol for WAN

links

Answer: A and D

The International Organization for Standardization (ISO)

modified SDLC to create HDLC (High-Level Data-Link Control)

protocol and SDLC remains the primary SNA link-layer protocol

for WAN links. The Institute of Electrical and Electronic

Engineers (IEEE) modified HDLC to create IEEE 802.2. SDLC can

be used with point-to-point and multipoint links.

What two types of network nodes does SDLC (Synchronous Data-

Link Control) identify?

A. main

B. primary

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C. backup

D. secondary

Answer: B and C

SDLC identifies two types of network nodes: primary and

secondary. Primary nodes set up and tear down links and

manages links while they are operational, control the

operation of other stations called secondaries, and polls the

secondaries in a predetermined order. Secondary nodes are

controlled by primary stations. Secondaries can only send

information to the primary if permission is granted by the

primary.

In what four configurations can SDLC (Synchronous Data-Link

Control) primary and secondary nodes be connected?

A. Loop

B. Point-to-Point

C. Hub go-ahead

D. Ring

E. Multipoint

Answer: A, B, C, and E

The four configurations that SDLC (Synchronous Data-Link

Control) primary and secondary nodes can be connected are

Loop, Point-to-Point, Hub go-ahead, and Multipoint. Loop

configuration involves a loop topology with the primary

connected to the first and last secondaries. Point-to-Point

configuration involves two nodes, one primary and one

secondary. Hub go-ahead configuration involves an inbound and

outbound channel. The primary uses the outbound channel to

communicate with the secondaries and the secondaries use the

inbound channel to communicate with the primary. Multipoint

configuration involves one primary and multiple secondaries.

What are two differences between HDLC (High-Level Data-Link

Control) protocol and SDLC (Synchronous Data-Link Control)

protocol?

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A. HDLC does not support synchronous full-duplex operation but

SDLC does

B. HDLC and SDLC do not share the same frame format

C. HDLC does not support the Loop or Hub go-ahead

configurations but SDLC does

D. HDLC supports three transfer modes but SDLC only supports

one

Answer: C and D

Two differences between HDLC protocol and SDLC protocol are

that HDLC does not support the Loop or Hub go-ahead

configurations but SDLC does and HDLC supports three transfer

modes but SDLC only supports one. HDLC supports NRM (Normal

Response Mode), ARM (Asynchronous Response Mode), and ABM

(Asynchronous Balanced Mode). On the other hand, both HDLC and

SDLC support synchronous full-duplex operation and they both

share the same frame format.

What are the three general categories of X.25 devices?

A. DTE

B. DCE

C. PLP

D. PSE

Answer: A, B, and D

The three general categories of X.25 devices are DTEs (data

terminal equipment), DCEs (data circuit-terminating

equipment), and PSEs (packet switching exchanges). DTEs are

end system devices that communicate across the X.25 network.

They are normally CPE (customer premise equipment) such as

PCs, network hosts, routers, terminals, etc. DCEs are

communication devices such as modems. They provide the

interface between the DTE and the PSE. PSEs are switches that

are the bulk of the carriers network. They transfer data from

one DTE to another.

What three layers of the OSI reference model does the X.25

protocol map to?

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A. Transport

B. Network

C. Data Link

D. Physical

Answer: B, C, and D

The X.25 protocol maps the lowest three layers of the OSI

reference model. These are the Physical layer, Data Link

layer, and Network layer.

Match the following X.25 protocols, PLP and LAPB, with the OSI

reference model layers that they map to.

A. PLP Physical

B. PLP Network

C. PLP Data Link

D. LAPB Physical

E. LAPB Data LinkF. LAPB Network

Answer: B and E

The protocols typically used in X.25 are PLP (Packet-Layer Protocol)

and LAPB (Link-Access Procedure, Balanced). PLP is a network layer

protocol and LAPB is a data-link layer protocol. PLP manages packet

exchanges between DTE devices across virtual circuits. PLP operates in

five modes: call setup, data transfer, idle, call clearing, and

restarting. LAPB manages communication and packet framing between DTE

and DCE devices.

ATM (Asynchronous Transfer Mode) Switching is a:

A. connectionless oriented protocol

B. synchronous protocol

C. connection oriented, synchronous protocol

D. connection oriented, asynchronous protocol

Answer: D

ATM (Asynchronous Transfer Mode) Switching is a connection

oriented, asynchronous protocol. It is usually used when high-

speed transfer of voice, data, and video is needed.

What layers of the OSI reference model does ATM (Asynchronous

Transfer Mode) map to? Choose two.

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A. Physical

B. Data link

C. Network

D. Transport

Answer: A and B

ATM (Asynchronous Transfer Mode) maps to the Physical and Data Link

layers of the OSI reference model.

Which of the following two are ATM (Asynchronous Transfer

Mode) network interfaces?

A. ANI

B. TNI

C. UNI

D. NNI

Answer: C and D

The two primary ATM interfaces are UNI (User network

interface) and NNI (Network node interface). UNI and NNI can

be further subdivided into public or private UNIs and NNIs.

Private UNI Connects an ATM endpoint and a private ATM

switch.

Public UNI Connects an ATM endpoint or private switch to a

public ATM switch.

Private NNI Connects two ATM switches within the same

private organization.

Public NNI Connects two ATM switches within the same public

organization.

ATM supports only point-to-point connections.

A. True

B. False

Answer: B

ATM supports both point-to-point and multipoint connections.

Which of the following ATM (Asynchronous Transfer Mode)

adaptation layers is used to transfer classical IP data over

ATM?

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A. AAL1

B. AAL2

C. AAL3/4

D. AAL5

Answer: D

The following are the ATM adaptation layers:

AAL1 used for handling circuit emulation

AAL2 multiplexes short packets from multiple sources into a

Single cell

AAL3/4 designed for network service providers

AAL5 the primary AAL for data. Used to transfer classical IP

data over ATM and LAN emulation (LANE). Also known as

SEAL (Simple and Efficient Adaptation Layer)

Which of the following best describes ATM (Asynchronous

Transfer Mode)?

A. It is a token passing protocol like Token Ring but much faster.

B. It is a modem technology that used existing telephone wires

to transport high bandwidth data.

C. It is a cell-switching and multiplexing technology that

combines the benefits of circuit switching and packet

switching.

D. It is a protocol used for transporting SNA and NetBIOS

traffic over an IP network.

Answer: C

ATM is a cell-switching and multiplexing technology that combines the

benefits of circuit switching and packet switching. It is not a modem

technology that uses existing telephone wires to transport high

bandwidth data because that is ADSL (Asymmetric Digital Subscriber

Line). It is not a protocol used for transporting SNA and NetBIOS

traffic over an IP network because that is DLSw (Data-Link Switching).

An ATM (Asynchronous Transfer Mode) cell consists of 53 octets, or

bytes.

A. True

B. False

Answer: A

An ATM (Asynchronous Transfer Mode) cell consists of 53 octets, or

bytes. The first five bytes contain cell-header information and the

remaining 48 bytes contain the user data, which is also known as

"payload".

When used on fiber-optic cabling, ATM (Asynchronous Transfer

Mode) supports speeds up to OC-192 (9.952 Gbps) and beyond.

A. True

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B. False

Answer: A


Mode) supports speeds of up to OC-192 (9.952 Gbps) and beyond,

especially if technologies such as WDM (Wave Division

Multiplexing) are used. Copper cabling can support speeds at

or above T3 when used with ATM.

What are two motivating factors for using ATM (Asynchronous

Transfer Mode) as a WAN core technology?

A. ATM is a good choice for customers with limited QoS

(Quality of Service) requirements

B. ATM is a good choice for customers with decreasing

bandwidth requirements

C. ATM is a good choice for customers who want to save money

spent on monthly tariffs for WAN circuits

D. ATM is a good choice for customers who need very large

bandwidth requirements

Answer: C and D

One motivating factor for using ATM (Asynchronous Transfer

Mode) as a WAN core technology is saving money spent on

monthly tariffs for WAN circuits. Customers can often have

fewer WAN links with ATM than with older technologies such as

leased lines or TDM (Time Division Multiplexing). Another

motivating factor is that ATM can support very high bandwidth.


Mode) supports speeds of up to OC-192 (9.952 Gbps) and beyond,

especially if technologies such as WDM (Wave Division

Multiplexing) are used. Copper cabling can support speeds at

or above T3 when used with ATM.

What are two purposes of a LAN switch?

A. It initiates circuit establishment

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B. It provides much higher port density at a lower cost than

traditional bridges

C. It breaks up collision domains and increases the available

bandwidth per user

D. It breaks up broadcast domains

Answer: B and C

A LAN switch provides much higher port density at a lower cost

than traditional bridges. It breaks up collision domains and

increases the available bandwidth per user. Using LAN switches

allows you to microsegment (fewer users per segment). By

microsegmenting, each user receives instant access to the full

bandwidth and does not have to contend for available bandwidth

with other users.

What are two common switching/forwarding methods used by LAN

switches?

A. Multiple forwarding

B. Cut-through

C. Redundant

D. Store-and-froward

Answer: B and D

Cut-through and store-and-forward are two common

switching/forwarding methods used by LAN switches. Cut-through

switching copies only the destination address into the LAN

switches onboard buffers before it forwards the frame to its

destination. It has the lowest latency of these two methods.

Store-and-forward switching copies the entire frame onto the

onboard buffers and computes a CRC (cyclic redundancy check)

before it forwards the frame to its destination. Latency

depends on the size of the frame.

An ATM switch forwards frames.

A. True

B. False

Answer: B

An ATM switch forwards cells whereas a LAN switch forwards frames. ALAN switch is sometimes called a frame switch and an ATM switch is

sometimes called a cell switch.

LAN switches can be categorized according to the OSI layer at

which they forward and filter frames or switch frames. What

are these three categories?

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A. Layer 2

B. Layer 3

C. Layer 2 with Layer 3 features

D. Multi-layer

Answer: A, C, and D

The three categories that switches can be placed into

according to the OSI layer at which they forward and filter

frames or switch frames are Layer 2, Layer 2 with Layer 3

features, and Multi-layer. A Layer 2 LAN switch performs

switching and filtering based on the Data-link layer MAC

address. A Layer 2 LAN switch with Layer 3 features can make

switching decisions based on more information other than the

Layer 2 MAC address such as Layer 3 traffic control features.

A Multi-layer switch makes switching and filtering decisions

based on Layer 2 and Layer 3 addresses.

Transparent bridges implement the spanning-tree algorithm

(SPA) to prevent bridging loops.

A. True

B. False

Answer: A

Transparent bridges and switches implement the spanning-tree

algorithm (SPA) to prevent loops. SPA was developed by Digital

Equipment Corporation.

Some switches have the capability to automatically move from

cut-through switching mode to store-and-forward switching

mode. This type of switching is called:

A. Cut-through-forward switching

B. Store-and-forward-cut switching

C. Forward-cut switching

D. Adaptive cut-through switching

Answer: D

A problem with cut-through switching is that it forwards

frames with CRC errors and illegal frames such as runts. Cut-through switching should not be used on a network that is

prone to these errors and illegal frames. Some switches have

the capability to automatically move from cut-through

switching mode to store-and-forward switching mode when an

error threshold is reached. This type of switching is called

adaptive cut-through switching.

Which Cisco IOS command identifies Layer 2 errors, router

errors such as dropped or ignored packets, and broadcast

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rates.

A. show version

B. show interface

C. show buffers

D. show processes

Answer: B

The Cisco IOS router command "show interface"

will identify Layer 2 errors such as dropped packets.

Which Cisco IOS command identifies router CPU usage,

including CPU time used by processes?

A. show version

B. show interface

C. show buffers

D. show processes

Answer: D

The Cisco IOS router command "show processes" will identify router CPU

utilization.

Which Cisco IOS command checks buffer usage and buffer misses?

A. show version

B. show interface

C. show buffers

D. show processes

Answer: C

The Cisco IOS router command "show buffers" will

report on buffer utilization.

ISDN protocols that begin with "E" deal with?

A. International Telephone Numbering Plan

B. International ISDN addressing

C. Concepts, structures and terminologyD. User Network Interface (UNI)

E. LAPD

Answer: A and B

E.163 is used for International Telephone Numbering Plan and

E.164 is used for International ISDN addressing.

ISDN protocols that begin with "I" deal with?

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A. Concepts, structures and terminology

B. User Network Interfaces (UNI)

C. LAPD

D. ISDN network layer between switch and terminal

E. International ISDN addressing

Answer: A and B

I.100 series is used for concepts, structures and

terminology. I.400 Series is used for UNIs.

ISDN protocols that begin with "Q" deal with?

A. International ISDN addressing

B. Concepts, structures and terminology

C. UNIsD. LAPD

E. ISDN network layer between terminal and switch

Answer: D and E

Q.921 is used for LAPD on the D channel. Q.931 is used for

ISDN network layer between terminal and switch.

Which of the following converts BRI signals into a form used

by ISDN?

A. TE1

B. NT2

C. NT1

D. TE2

E. TA

Answer: C

TE1 is used to designate a router as a device having native

ISDN interface. NT2 is for ISDN lines at the customer sitewhich are switched using a customer switch. TE2 is used to

designate a router as a device needing a TA for BRI signals.

TA is used to convert EIA/TIA-232, V.35 signals into BRI

signals.

What are the two access options for ISDN?

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A. BRI

B. PRI

C. local telephone company

D. a long distance provider

E. DDR

Answer: A and B

BRI has two 64 kbps bearer channels plus one 16 kbps data

channel. BRI connects to an NT1. PRI is available in North

America and Japan. It has 23 bearer channels and one 64

kbps D channel. In Europe PRI has 30 B channels and one D

channel.

AppleTalk addresses consist of what three elements?

A. Network numberB. Node number

C. Socket number

D. Zone number

Answer: A, B, and C

AppleTalk addresses consist of a network number, a node

number, and a socket number. They are usually written as

decimal values separated by a period. For example, 3.2.40

means Network 3, Node 2, Socket 40. It is also sometimes

represented as 3.2, Socket 40. The Network number is 16 bits,

the Node number is 8 bits, and the Socket number is 8 bits.

An address must be statically assigned to an AppleTalk device.

A. True

B. False

Answer: B

It is not necessary to statically assign an address to an

AppleTalk device. AppleTalk nodes are assigned addressesdynamically when they first attach to a network.

Which of the following is responsible for establishing and

maintaining routing tables for AppleTalk routers?

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A. RIP

B. AURP

C. RTMP

D. ATP

Answer: C

RTMP (Routing-Table Maintenance Protocol) is a transport-layer

protocol that is responsible for establishing and maintaining

routing tables for AppleTalk routers. It is based on the

Routing-Information Protocol (RIP) and uses hop count as a

routing metric.

What are the three options available for routing in AppleTalk

networks?

A. RIP (Routing-Information Protocol)

B. RTMP (Routing-Table Maintenance Protocol)C. AURP (AppleTalk Update-Based Routing Protocol)

D. Enhanced IGRP for AppleTalk

Answer: B, C, and D

The three options available for routing in AppleTalk networks

are RTMP, AURP, and Enhanced IGRP for AppleTalk. RTMP is the

most common option because it is easy to configure and is

supported by most vendors of multi-protocol routers. To reduce

the amount of traffic caused by RTMP (an RTMP router sends its

routing table every 10 seconds using split horizon), large

enterprises have the option of using AURP or Enhanced IGRP for

AppleTalk in the core of their internetworks.

What information is needed to choose a CIR (Committed

Information Rate) for a Frame Relay network? Choose three.

A. Amount of expected interactive traffic

B. Amount of expected bandwidth regeneration

C. Amount of expected file and transfer traffic

D. Amount of expected broadcast traffic

Answer: A, C, and D

In addition to verifying interactive traffic, transfer trafficand expected broadcast traffic, you will want to consider the

Cisco IOS version of your internetworking routers. Some Cisco

IOS versions do not have the updated capability of traffic

shaping that will increase your control over the network.

The following are the four steps in establishing an X.25

virtual circuit. Place them in the correct order.

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A. The PSE (Packet Switch Exchange) passes the packet to the

next remote DCE

B. The local DCE packet binder sends packet to the closest PSE

(Packet Switch Exchange)

C. The source DTE sends packet to the local DCE

D. The remote DCE examines the packet header of destination DTE

Answer: C, B, A, and D

The correct order of the four steps used in establishing an

X.25 virtual circuit are as follows:

1.)The source DTE sends packet to the local DCE

2.)The local DCE packet binder sends packet to the closest

PSE (Packet Switch Exchange)

3.)The PSE (Packet Switch Exchange) passes the packet to the

next remote DCE

4.)The remote DCE examines the packet header of destination

DTE

The Cisco 1900 switch IOS can be configured through a menu

system and what else?

A. Set-based CLI

B. IOS-based CLI

C. Pruning system

D. VTP trunk

Answer: B

The Cisco 1900 switch IOS can be configured through a menu

system and an IOS-based CLI (Command-Line Interface).

What type of cable do you use when you connect two switches?

A. rollover cable

B. cat5 cable

C. crossover cable

D. straight-through cable

Answer: C

You should use a crossover cable when you connect two switches.

It is possible to configure a switch through the Internet.

A. True

B. False

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Answer: A

You can configure a switch through the Internet using the

Virtual Switch Manager (VSM). To do this, you have to type in

the IP address of the switch at the Web browser.

What happens when you press the mode button on the 1900 switch?

A. Nothing. The 1900 switch has no buttons, only ports

B. You see three different status lights

C. It puts you in broadcast mode

D. It puts the switch in stand-by mode

Answer: B

When you press the mode button on the 1900 switch, you see

three different status lights. It is the only button on the

1900 switch. The status lights are:

Stat shows status of the ports. Green is active, blinking

green is activity, amber means a link fault has occurred.

UTL indicates the bandwidth of the switch.

FDUP shows you which ports are configured at full duplex

If you have a console cable connected to the 1900 switch and

you power the switch up, what menu options do you see if the

IP configuration is not set? Choose three.

A. [M]

B. [S]

C. [K]

D. [I]

E. [C]

Answer: A, C, and D

If you have a console cable connected to the 1900 switch and

you power the switch up the menu options you see if the IP

configuration is not set are:

[M] Menus

[K] Command Line[I] IP Configuration

Once the IP configuration is set, the [I] selection will no

longer appear.

How many ports are available on the 1900 series switches?

Choose two.

A. 8

B. 12

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C. 16

D. 24

Answer: B and D

The 1912 switch has 12 ports and the 1924 switch has 24 ports.

These ports are 10BaseT ports. Each switch also has one or two

FastEthernet uplinks to connect to other switches. These are

either 100BaseT or 100BaseFX.

At which layers of the OSI reference model does frame relay

operate? Choose two.

A. Network

B. Data Link

C. Physical

D. Transport

Answer: B and C

Frame Relay operates at the Physical and the Data Link layers of the

OSI reference model.

What two general categories do frame relay devices fall under?

A. CSU

B. DSU

C. DTE

D. DCE

Answer: C and D

The two general categories that frame relay devices fall under are Data

Terminating Equipment (DTE) and Data Circuit-terminating Equipment

(DCE). DTEs are usually customer premise equipment (CPE) such as

terminals, PCs, routers, bridges, etc. DCEs are carrier owned

internetworking devices. DCEs provide clocking and switching services

in a network.

Which of the following are true regarding a DLCI (Data-Link Connection

Identifier)? Choose two.

A. It identifies a Frame Relay virtual circuit

B. It helps a Token Ring network identify the active monitor

C. It is usually assigned by the Frame Relay service provider

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D. It must be the same for all DTE devices on the WAN

Answer: A and C

A Frame Relay virtual circuit is identified by a DLCI (DataLink

Connection Identifier). It is usually assigned by the Frame Relay

service provider, such as a telephone company. DLCI numbers have local

significance, so two DTE devices connected by a virtual circuit may be

assigned a different DLCI number on each end of the connection. DLCI

has nothing to do with Token Ring.

Frame Relay implements two congestion notification mechanisms.

What are they?

A. DLCI

B. CSMA

C. FECN

D. BECN

Answer: C and D

The two congestion notification mechanisms implemented by Frame Relay

are FECN (Forward-explicit congestion notification) and BECN (Backward-

explicit congestion notification). Both of these are controlled by a

bit contained in the Frame Relay header. The Frame Relay header also

contains a DE (Discard Eligibility) bit that is used to identify less

important traffic that can be dropped during periods of congestion.

Which of the following are related to Frame Relay? Choose

three.

A. CIR

B. Be

C. Bc

D. BGP

Answer: A, B, and C

CIR (Committed information rate) is the rate at which a Frame

Relay network agrees to transfer information under normal

conditions averaged over a minimum increment of time. Bc

(Committed Burst) is the maximum amount of data, in bits, that

a Frame Relay network is committed to accept and transmit at

the CIR. Be (Excess Burst) is the number of bits that a FrameRelay network will attempt to transmit after Bc (Committed

Burst) is accommodated. CIR, Bc, and Be are all negotiated

tariff metrics.

Which of the following are true regarding LMI (Local

Management Interface)? Choose two.

A. The LMI is a set of enhancements to the Frame Relay

specification

B. It can be used only with an SVC (Switched Virtual Circuit)

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C. It was developed by IBM

D. It offers a number of features called extensions for

managing complex internetworks

Answer: A and D

The LMI is a set of enhancements to the Frame Relay

specification. It was developed by StrataCom, Northern

Telecom, Digital Equipment Corporation, and Cisco Systems. It

offers a number of features called extensions for managing

complex internetworks. LMI extensions include global

addressing, virtual-circuit status messages, and multicasting.

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