Ran across this one ( again, after a long time ) It can serve as a good starting point for a lot of layer two questions. http://www.cavebear.com/CaveBear/Ethernet/index.html also, if you are interested in higher level and more general information, much of it techno-political, start at the cavebear home page and have some fun. Particularly, check out the products. Chuck Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=18231&t=18231 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]