Networking Basics Questions and Answers

Answer: D

Correct answer: overlay network

An overlay network is built as a logical topology on top of an existing physical one: its links are paths, possibly many hops long, through the underlying network. Peer-to-peer systems, VPNs and content distribution networks are all overlays. The advantage is that new services can be deployed without changing the infrastructure beneath; the cost is that the overlay cannot see the real topology and may route inefficiently across it.

Answer: D

Correct answer: VTP is used to send VLAN information to switches in a configured VTP domain.

VLAN Trunking Protocol propagates the VLAN database from a server switch to the clients in the same VTP domain, so a VLAN created once appears throughout. The other statements are false: only VLAN 1 exists by default, not two; VLANs are a standard function that works with equipment from any manufacturer; and there is no ten-switch limit on a VTP domain.

Answer: A

Correct answer: broadcast network

In a broadcast network a single communication channel is shared by every machine, so a frame sent by one is received by all and each decides from the address field whether the frame is meant for it. Classic Ethernet on a hub and wireless LANs work this way, which is why they need a media access control method. Unicast and multicast describe the intended set of recipients of a particular transmission, not how the channel itself is arranged.

Answer: B

Correct answer: show interface

show interface reports the line status and line protocol status, and on a Frame Relay interface it also shows the LMI type and DLCI information. show frame-relay pvc gives fuller PVC detail - the DLCI status and the congestion counters - but not the line and protocol status of the interface itself, which is why the single interface command is the one that covers all four items asked for.

Answer: D

Correct answer: RouterA(config-if)#clock rate 64000

Where the router provides the DCE function it must supply the clocking, and clock rate is set in bits per second under the interface, hence 64000 rather than 64. bandwidth is a quite different command: it sets a value used by routing protocols in their metric calculations and by QoS, and changing it has no effect whatever on the actual line speed.

Answer: A

Correct answer: Syntax

Syntax is the structure or format of the data - the order of the fields, the number of bits in each, where the address sits and where the payload begins. Semantics is what those bits mean and what action they call for; timing concerns when data may be sent and how fast. The three together make up a protocol, and this question isolates the first of them.

Answer: D

Correct answer: 1 and 3

The two main types are standard and extended. A standard access list filters on the source address only and is placed close to the destination; an extended list filters on source and destination address, protocol and port, and is placed close to the source so that unwanted traffic is dropped before it crosses the network. IEEE and Specialized are not access list types at all.

Answer: B

Correct answer: copy running-config startup-config

The running configuration lives in RAM and is lost at reload; the startup configuration lives in NVRAM and is what the router reads on boot. Copying one to the other saves the current settings, and the abbreviation copy run start is the form most often typed. The older write memory did the same job on earlier IOS versions and survives as a deprecated alias, but the copy form is the current command.

Answer: D

Explanation: In a computer network, a node can be anything that is capable of sending data or receiving data or even routing the data to its destination. Routers, Computers and Smartphones are some examples of network nodes.

Answer: B

Correct answer: Physical layer

A hub simply regenerates and repeats the electrical signal out of every other port. It reads no addresses, makes no forwarding decisions and does not examine frames at all, so it belongs to the physical layer - it is a multiport repeater. A switch, which reads MAC addresses and forwards selectively, is a data link layer device, and a router, which reads IP addresses, is a network layer device.