Switches and collision domains

Kroenecker · 10-11-2004, 08:43 AM

Is port-to-port switching considered to be a single collision domain? Now segment switching creates separate collision domains...but my instructor insists that if you have single nodes connected to a switch you have a single collision domain. That makes no sense to me.

scowles · 10-11-2004, 10:31 AM

If I'm understanding your post correctly, then I think your instructor may need to reread the chapter on OSI layer 2.

To answer your question: A "typical" switch opertates at layer 2 of the OSI model. So each switch port creates is its own collision domain (AKA: micro-segmentation - according to cisco curriculum). So if you have 8 hosts connected to an 8-port switch, you would have 8 collision domains. A hub is a layer 1 device, so if you had 8 hosts connected to an 8 port hub, then you would have a single collision domain.

Kroenecker · 10-15-2004, 02:33 AM

Thanks for the response. I have since talked to another student in my class who has been working in the field for several years, but is back in school to get certification, and he told me that our instructor is constantly making mistakes

I'm a math graduate and I've noticed that he also has a very weak grasp of certain math concepts. I would feel sorry for him except, wait...no, I'm paying money to go to his class.

Nuf of my rant