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New Member

mac addressing

ok as we all say a picture is worth 1000 words, so there you have it.

this is a question from testking about mac adreessing btween a server and a host divided by a router....

now i dont think the answer is a mistake becouse this is the secound time i see it...

can anyone please explane the answer. as far as i know (and anyone else i know knows) the mac adress will allways change when going threw a router.


Accepted Solutions

Re: mac addressing

Hall of Fame Super Silver

Re: mac addressing

The setup shown would result in the source MAC interface being that of the router interface E0 (assuming that's a switch under the text).

The "D" answer given appears incorrect to me.

Hope this helps. Please rate hgelpful posts.

Re: mac addressing

Unless the router is configured for bridging between e0 and e1 and all switches are layer 2 (which is an unknown at this point), I agree with Marvin, it will be the mac-address of E0 that will be the source add of the frame that PC A receives.

Rule of thumb, Mac-addresses change when they cross layer 3 boundaries.


PS: please rate all posts!

New Member

Re: mac addressing

are you sure... i didnt post it but they even got an explenation that goes.

"even thou the transmition is going threw a router the source and destination mac adress will not change"

i am with you on this... but i am not sure were right in this matter.

Re: mac addressing


Re: mac addressing


I think the confusion might come from the fact the the source and destination MAC address indeed change at every interface of the router, but the source and destination IP do not.

You might want to have a look at this link, it has a graphic explanation on how the process works...

The IP Routing Process



New Member

Re: mac addressing

and just so i'll rest your spirit.

i am going to do the CCNA exam BUT.

i went threw semester 1 and 2 from cisco studies (i stoped becouse it was BORRING)


i learend the entire content of "testout" (which i recommend dearly its very good)

and i went threw some vidios from CBTnuggets on things i wanted to go over again.

i am not a cheater and i dont think that doing the questions from testking is anymore then another practice.

anyways. thanks for your answer but i will come back to you on this is it gets wrong on the exam heh :)

Re: mac addressing


I didnt mean to call you a cheater, but test question vendors that are out there are very unreliable.


New Member

Re: mac addressing

i know you didnt but i'll have to agree with you on this. testking isnt the most reliable thing out there to say the least.

New Member

Re: mac addressing

I am sure with your guess.

MAC address changes each timt it goes through the router.

Testking answer "D" seems definetly wrong.


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