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How to prevent MAC Flooding?

Hi Friends,

Iam studing ICND1 Book for CCNA there is an quiz question see the attached pix.

First of my question is how can a switch forward a frame that is having same source and dest MAC address?

Second question is will port secuirty commands can prevent this MAC flooding? or we need somthing else to stop it

I would love to have nice & "practical" answers for my two queries from you peeps :)

NOTE ( NO LINKS please)

Thanks
Ashu
1.JPG

ReN501

ok for question one , it is a security related attack, basically , this attack consumes the small amount of memory the switch has to store mac adress info , with the ultimate agenda to force the switch into a mode unlike a hub ( all data down all ports )where packet sniffing software can be then used to grab sensitive info.

second question check out :-
sh mac-address-table unicast-flood
should give you some info on limiting or prevention

acl-puzz

ASKER

REN501

Thanks for replying but my

1 question is "HOW" can a switch forward a frame that is having same source and dest MAC address? can u tell me "HOW" its done?

2 sh mac-address-table unicast-flood this command is not there..in Packet tracer so cant test it!!

SOLUTION

ReN501

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ASKER CERTIFIED SOLUTION

rfc1180

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acl-puzz

ASKER

ty rfc1180 <--- i love urs name its concludes whole TCP/IP lol

what about second query :) ?

rfc1180

acl-puzz, Thanks! I believe the second query was already addressed by giving you a link; essentially, the whole point in MAC flooding is obviously to consume memory and cpu resources, the best and quick way to avoid this is only assign the MAC addresses that are supposed to be on the ports:

switchport port-security would be your solution to prevent the MAC Flooding

as indicated in the link that ReN501 gave you.

Good Luck
Billy