[EMAIL PROTECTED] wrote: > > Question: > > I am just going to generalise here. Lets take just one port of > a switch or > one collision domain since that's what switches do. > > If we run 10 or 100 Half Duplex to a switch ... Is there a > chance of a > collision occuring?
Yes. > If we then run 10 or 100 Full Duplex to a switch ... Is there a > chance of a > collision occuring, besides late collisions, etc. No, collisions have no meaning in full duplex. > > From what I have read (or remember to have read): > When we run in full duplex we have seperate TX/RX wire pairs > i.e the TX pair > on one side is wired to the RX pair on the other side and vice > versa... Well, I see you have gotten some good basic answers, but I'm going to make you do some more thinking and generalize even more than you already have. ;-) The TX is always wired to the RX on the other side . Transmit has to be converted to receive or there's no point in doing networking at all! Either a hub or switch better do this. If not, then you better use a cross-over cable. What makes full duplex different is that receiving on your RX circuit (which is the other side's TX circuit) is OK. With old-style Ethernet, receiving while you were sending was a collision. Only one station could send at a time. What you actually read is that for full duplex to work each side must have a dedicated TX and RX circuit. The point of that statement is that full duplex doesn't work on coax cable. Coax cable has a single copper core that is used by all stations on the bus for both TX and RX. > hence there should be no collisions and that's why there is no > collision > detection mechanism in 100MB ... Right? As Michael said, what you mean to say is that there's no collistion detection on full duplex. 100 Mbps supports both half and full. So does 10 Mbps. > > But the reason I ask this, is that yesterday I had a problem > with a NIC, and > the options I had listed in the NIC Device Driver Software was > this: 100Mb > Half Duplex. I thought 100Mb could only run in full duplex? > However when we > run Half Duplex, the TX/RX occurs on then same wire pair so how > does 100Mb No, when you run half duplex in a 10Base-T environment with twisted pair cabling, each side still has its own TX pair, (which is RX on the other end). But receiving while sending is a collision. > Half Duplex work if there is no collision detection mechanism > for 100Mb? 100 Mbps supports collision detection. It's just disabled when full duplex is used. Priscilla > > Of course I could be completely wrong? > > Thanks > Manish > > Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=48944&t=48830 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
