Chapter 3: Fundamentals of WANs

Question 1

What is the main function of OSI Layer 1 as used in WANs?

Answer 1

Delivery of bits from one device to another.

Question 2

In the cabling for a leased line, what typically connects to a four-wire line provided by a telco?

Answer 2

A CSU/ DSU

Question 3

Which two Internet access technologies, used to connect a site to an ISP, offer asymmetric speeds?

Answer 3

DSL & Cable internet.

Question 4

A synonym for EoMPLS

Answer 4

Ethernet emulation

Question 5

What are three examples of internet access links?

Answer 5

Leased lines, cable, and DSL

Question 6

What protocol uses headers and trailers just like Ethernet?

Answer 6

EoMPLS, Ethernet over multiprotocol label switching

Question 7

What is the flag header comparable to Ethernet?

Answer 7

Preamble

Question 8

As part of HDLC what does Cisco add to the header, besides the standard for ISO.

Answer 8

The Type field.

Question 9

Routing Protocols serve what five main functions?

Answer 9

Routing table population, route selection, respond to changes in network topology, rapidly converge networks, prevent loops.

Question 10

Summarize the three steps in learning routes.

Answer 10

Router adds directly connected routes to routing table. A routing protocol learns routes from neighbors. Learned routes are added to the routing table.