Monday, February 25, 2013

Networking questions part 3

These questions are based on Cisco CCNA network exam, and I believe are also a good refresher to keep the mind active.  If you don't use it, you'll lose it as they say :-).

1. The Transport layer is...

A) Connectionless
B) Connection-oriented
C) Both

2. HDLC is ISO standard WAN protocol which means you don't need Cisco routers at both ends of a WAN connection, a router from any vendor that supports HDLC will work.

A) True
B) False

3. If your switch uses shared memory buffering, what would happen if a packet could not be delivered because of a busy destination port?

A) It would delay transmission of all packets in memory
B) It would be sent to the destination port anyway
C) It would wait in a queue while all other packets in memory are transmitted
D) It would drop the packet after an allocated time

4. Which switching mode is the most likely to forward frames containing errors?

B) Modified Cut-Through
C) Store-and-Forward
D) Cut-Through
E) Fragment-Free

5. When STP is converging no data can move through the switched network.

A) True
B) False

Clickbank Products

1. Correct Answer: C

2. Correct Answer: B

Explanation: Even though HDLC is an ISO standard, each vendor has their own version of HDLC.

3. Correct Answer: C

Explanation: The area of memory where the switch stores the data is called the memory buffer.

The memory buffer can use two methods for forwarding frames:

  • port-based memory buffering - In port-based memory buffering frames are stored in queues that are linked to specific incoming ports.
  • shared memory buffering - Shared memory buffering deposits all frames into a common memory buffer which all the ports on the switch share.

4. Correct Answer: D

Explanation: Cut-Through switching is also referred to by Cisco as Fast Forward.

When in cut-through mode the switch waits for the destination MAC Address to be received. Once the MAC Address is known the switch refers to its MAC filter table to determine which port the frame should be forwarded out. The switch forwards the frame even before the entire frame has arrived.

Frames with and without errors are forwarded in cut-through switching, leaving the error detection of the frame to the intended recipient.

5. Correct Answer: A

How did you go?