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need info on MAC learning process

say i have a switch with 5 ethernet ports. i have connected PCs to each one of them. Let us assume the MAC -IDs of the corresponding PCs are as listed below PC1----00:90:DB:12:13:11(150.50.50.11) PC2----00:90:DB:12:13:12(150.50.50.12) PC3----00:90:DB:12:13:13(150.50.50.13) PC4----00:90:DB:12:13:14(150.50.50.14) PC5----00:90:DB:12:13:15(150.50.50.15) now initially,when PC2 sends a file to PC5,how does the switch come to know that PC5 is connected to port 5 ? please explain the learning process. thanks in advance

Reply to
cheeku
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On 22.05.2007 17:18 cheeku wrote

Say you do your homework by your own. What's then left?

Arnold

Reply to
Arnold Nipper

Presuming no communications have gone on before this...and thus ARP/ CAM tables are empty...server 2 will send a broadcast arp to FF:FF:FF:FF:FF:FF to ask who owns 50.15. When the switch floods the ARP to all ports in that VLAN, server 5 will respond to the ARP, and thee switch will then populate its MAC/CAM table with the MAC of server 5 on port 5. Server 2 will then send the frames with the destination IP/MAC which the switch will then forward as needed to the matching MAC/Port.

In short, the switch populates its CAM table based on the source mac of any packet (I should say frame) received on the port. The CAM table matches ports to MACs.

Reply to
Trendkill

Guys, we need to stop doing this one's homework assignments. He snookered a few of us the first time. Obvious now.

Reply to
Brian V

Sorry.....hopefully his first interview is with one of us then. Be nice to see the deer in the headlights look.

Reply to
Trendkill

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