2 networking questions

Hey,

I'd like to get some clarification on a point that Indebluez made above. He or she writes that collisions are bound to occur if using a single VLAN within a switched environment. Is that really the case, because I understood that all collisions were eliminated in a switched environment with NIC's set to full-duplex and CSMA/CD therefore disabled. And this would be the case regardless of the size of the VLAN. Even in the event of multiple broadcasts occurring simultaneously, I figure they would be queued by the switch, and forwarded in turn. So my question - are there circumstances in which collisions can still occur within a switched, full-duplex environment? If so, with CSMA/CD disabled, any collisions would go undetected by the sender, and require re-sending by higher layers, making for a slow recovery.

Cheers.

First question.

Think of VLANS as separate subnets (because they are). Since you need to be routed between subnets - collisions would not be a problem.

Second

Collisions would be a problem if you have a hub running off of a switch. You also have a problem when you have a server sitting on one of the ports and you have multiple workstations accessing the server.

Normally, in a switched environment you would have a virtual path between 2 ports that no other port sees. This is also the case here. But now you have multiple ports - each with a virtual path to the server port.