Chapter 9

Question 1

How fast is a T-1 connection?

Answer 1

1.544 Mbps

Question 2

Circuit switched network

Answer 2

Requires the two nodes to create a dedicated communications channel and all data flows through one path

Used by plain old telephone service (POTS)

Question 3

Packet switched network

Answer 3

Divides the data into packets, which can make their own way to the destination.

Allocates the transmission capacity based on demand

No connection establishment and release needed unlike circuit switch networks

Question 4

Virtual Private Network (VPN)

Answer 4

Provides the equivalent of a private packet-switched network over the public internet. It involves establishing a series of PVC’s that run over the internet so that the network acts like a set of dedicated circuits even though the data flows over the internet

Question 5

Switched backbones

Answer 5

Use star topology

Most common type of BN used in the distribution layer

Switches come in different form factors

More common to locate centrally in main distribution facility (MDF) or other wiring closets

Question 6

Routed Backbone network

Answer 6

Sometimes called subnetted backbones or hierarchical backbones

Typically used at core layer, but sometimes at distribution layer

Advantages: LAN segmentation

Disadvantages: tend to be slower. More expensive. Harder to manage

Question 7

Permanent Virtual Circuits (PVC)

Answer 7

The connections between the different locations in the packet network. They are defined for frequent and consistent use by the network. They are not changed unless the network manager changes the network.

Question 8

Switched Virtual Circuits (SVC)

Answer 8

Change dynamically based on traffic