ccna interview questions and answers

Part - 45 CCNA Interview Questions and Answers

231 Describe End to End network services: (Choose all that apply)

A.) Best Route selection

B.) Accomplished Segment by Segment, each segment is autonomous

C.) Flow Control & Data Integrity

D.) Best efforts packet delivery

Ans A B C D

All of the above End to End network services.

232 Which of the following provide correct information about a protocol at the transport layer of the OSI model?

A.) UDP - Provides Connectionless datagrams service

B.) TCP - Provides Connection Oriented Services

C.) SMTP - Provides Mail Exchange

D.) IP - Route determination

E.) TCP - Provides Flow Control and Error Checking

F.) FTP - Transfers of Files

Ans A B E

Only TCP and UDP work at the Transport layer of the above choices. IP is a Network layer protocol. SMTP and FTP are application layer protocols.

233 Which protocol works at the Internet layer and is responsible for making routing decisions?

A.) UDP

B.) IP

C.) TCP

D.) ARP

Ans B

Internet Protocol - IP provides routing and a single interface to the upper layers. No upper layer protocol and now lower layer protocol have any functions relating to routing. IP receives segments from the transport layer and fragments them into packets including the hosts IP address.

234 Which layer is responsible for providing mechanisms for multiplexing upper-layer application, session establishment, and tear down of virtual circuits?

A.) Session

B.) Network

C.) Physical

D.) Transport

E.) Application

F.) Presentation

Ans D

The Transport layer does the following: Responsible for end-to-end integrity of data transmission. Handles multiplexing upper-layer application, session establishment and tear down of virtual circuits. Hides details of network dependent info from the higher layers by providing transparent data transfer. The 'windows' works at this level to control how much information is transferred before an acknowledgement is required.

235 Which of the following are logged when IP access list logging is enabled?

A.) source address

B.) protocol

C.) source port

D.) destination address

E.) access list number

F.) destination port

Ans A B C D E F

All of the above are logged when IP access list logging is enabled.

236 What's the default CDP holdtime in seconds for Cisco routers?

A.) 30 seconds

B.) 180 seconds

C.) 90 seconds

D.) 60 seconds

Ans B

Cisco Discovery Protocol is a proprietary protocol to allow you to access configuration information on other routers and switches with a single command. It uses SNAP at the Data-Link Layer. By default CDP sends out a broadcast every 60 seconds and it holds this information for 180 seconds. CDP is enabled by default.

237 Which two of the following protocols are used at the Transport layer?

A.) ARP

B.) UDP

C.) ICMP

D.) RARP

E.) TCP

F.) BootP

Ans B E

TCP and UDP operate at the Transport layer.

238 LAN stands for which of the following?

A.) Local Area Network

B.) Local Arena Network

C.) Local Area News

D.) Logical Area Network

Ans A

LAN stands for Local Area Network

239 Choose three reasons why the networking industry uses a layered model:

A.) It facilitates systematic troubleshooting

B.) It allows changes in one layer to occur without changing other layers

C.) It allows changes to occur in all layers when changing one protocol

D.) It clarifies how to do it rather than what general function to be done

E.) It clarifies what general function is to be done rather than how to do it

Ans A B E

Why do we have a Layered Model?
1) It reduces complexity
2) Allows for a standardized interface
3) Facilitates modular engineering
4) Ensures interoperable technology
5) Accelerates evolution
6) Simplifies teaching and learning

240 Which layer is responsible for identifying and establishing the availability of the intended communication partner?

A.) Application

B.) Presentation

C.) Transport

D.) Session

E.) Network

Ans A

The Application layer performs the following: Synchronizing sending and receiving applications. Program-to program communication. Identify and establish the availability of the intended communication partner, and determine if sufficient resources exist for the communication. Popular application protocols include WWW, SMTP, EDI, FTP, Telnet, and SNMP