Wide Area Networks

Which of the following encapsulates PPP frames in Ethernet frames and uses common PPP features like authentication, encryption, and compression?

A:

PPP

B:

PPPoA

C:

PPPoE

D:

Token Ring

Answer: C

PPPoE encapsulates PPP frames in Ethernet frames and uses common PPP features like authentication, encryption, and compression. PPPoA is used for ATM.

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How should a router that is being used in a Frame Relay network be configured to keep split horizon issues from preventing routing updates?

A:

Configure a separate subinterface for each PVC with a unique DLCI and subnet assigned to the subinterface.

B:

Configure each Frame Relay circuit as a point-to-point line to support multicast and broadcast traffic.

C:

Configure many subinterfaces in the same subnet.

D:

Configure a single subinterface to establish multiple PVC connections to multiple remote router interfaces.

Answer: A

If you have a serial port configured with multiple DLCIs connected to multiple remote sites, split horizon rules, stop route updates received on an interface from being sent out the same interface. By creating subinterfaces for each PVC, you can avoid the split horizon issues when using Frame Relay.

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Which command is required for connectivity in a Frame Relay network if Inverse ARP is not operational?

A:

frame-relay arp

B:

frame-relay map

C:

frame-relay interface-dci

D:

frame-relay lmi-type

Answer: B

If you have a router in your Frame Relay network that does not support IARP, you must create Frame Relay maps on your router, which provide known DLCI-to-IP address mappings.

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When a router is connected to a Frame Relay WAN link using a serial DTE interface, how is the clock rate determined?

A:

Supplied by the CSU/DSU

B:

By the far end router

C:

By the clock rate command

D:

By the Physical layer bit stream timing

Answer: A

Clocking on a serial interface is always provided by the CSU/DSU (DCE device). However, if you do not have a CSU/DSU in your nonproduction test environment, then you need to supply clocking with the clock rate command on the serial interface of the router with the DCE cable attached.

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Which of the following uses ATM as the Data Link layer protocol that's terminated at what's known as the DSLAM?

A:

DSL

B:

PPPoE

C:

Frame Relay

D:

Dedicated T1

Answer: A

ATM is the Data-Link layer protocol that's typically used over the DSL layer 1 connection from the CPE and terminated at what's known as the DSLAM-an ATM switch that contains DSL interface cards, or ATU-Cs.

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Questions for: Wide Area Networks