Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Announcements

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. If you'd prefer to explore, try our test area to get started. And see here for current known issues.

New Member

collisions in full-duplex ethernet

I've read a confusing question in switching exam. Here it is:

17. Which of the following are true of full-duplex ethernet?

a. There is a significant performance increase over half-duplex ethernet

b. More collisions

c. If one host is transmitting, the other must wait for it to finish

d. No collisions

e. Clients must have a full-duplex compatible ethernet card

Answers are: A,E

This seems right, but why D isn't true?

Thank you

  • Other Network Infrastructure Subjects
8 REPLIES
New Member

Re: collisions in full-duplex ethernet

Cant think why D isnt true except when the settings are mismatched and you have one device in full duplex the other in half duplex ie if auto negotiation has failed.

New Member

Re: collisions in full-duplex ethernet

This question would have confused me as well.

The only thing I can think of is during the auto-negotiation the devices use collisions to detect the correct settings.

Bobby

New Member

Re: collisions in full-duplex ethernet

Hi guys,

full-duplex ethernet, is jusr about using both uplink and donwlink for traffix. So, in full-duplex you tx and rx at the same time. If you use full-duplex in a shared media like a hub, you will FOR SURE have collisions....

pt

Purple

Re: collisions in full-duplex ethernet

"D" would normally be true but then again Cisco tests are very vague in a lot of their questioning and you end up guessing just what are they looking for .

New Member

Re: collisions in full-duplex ethernet

if 2 PC r sending and receiving data in full-duplex mode then there is no collisions between these 2 PC. but if another PC is attempting to send data at the same time to one PC, is there possibility to have collisions?

Re: collisions in full-duplex ethernet

No, there is no such possibility.

The Full Duplex circuit is between the SWITCH and the endstation. All traffic to other hosts is handled (queued) by the buffers in the switch.

Re: collisions in full-duplex ethernet

I remember that I had this question as well, and I assume that I filled in A,D,E as well. There are quite some questions like this in any exam I took (6 of them in 2002), presumably to prevent anyone from scoring 100%.

New Member

Re: collisions in full-duplex ethernet

Found an interesting comment in CCNA 640-607 certification guide on page 156. Says " If only one device is connected to each port on a switch, no collisions can occur." Take the implication and run with it.

6283
Views
5
Helpful
8
Replies
This widget could not be displayed.