Cascading Switches 2

[NFI]

Hello,

I'm trying to understand how switches work and Iw as hoping somebody could explain something to me, please?

I understand that a switch basically isolates all nodes attached to it and forwards data on to each by MAC address. It can do this because it knows all the MAC addresses of the devices attached to it, I presume?

How, then, does data go from a node attached to one switch to a node attached to another switch? Do switches share their ARP tables? That seems bit clever considering they're only switches... Or, does a switch treat another switch it is connected to like a gateway and just forwards all traffic bound for "unknown" MAC addresses to it? In that case, how does it recognise a switch and how would it deal with more than one switch being connected to it?

Is this all part of the Spanning Tree Protocol?

As you can see, I need help

Thanks,

Paul

 

[jimbopalmer]

No, it is not related to spanning tree.

No, switches do not share ARP tables.

It is all way more brute force than you may expect. When a switch gets a packet to an unknown MAC address, it floods it to EVERY port. It then remembers which port answers back, and in the future, (to 5 minutes, frequently) packets are only sent to the port that replied. (If more than one MAC address is on a port, I can guess that a switch or hub is attached to that port, but so far as I know, the switch does not use that fact) The size of the table is often 8,000 or 16,000 addresses, so for most organizations, you do not need to worry about table overflow. (which would cause more flooding)

I tried to remain child-like, all I acheived was childish.

 

[NFI]

Thanks for that - I thought switches probably weren't that clever...

Paul

 

[ellym]

I need to connect more than one switch of different manufacture how do i connect this switches to work as one switch?
Elly

 

[jimbopalmer]

I have never heard of cross vendor stacks of switches, ever. I may have missed it, but I doubt it.

I tried to remain child-like, all I acheived was childish.