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I hope I'm in the right stackexchange subsite (can't seem to find a networking related subsite..).
I've got 2 questions concerning the CSMA/CD network protocol:
Before sending some (say 5) messages over the bus, is there some kind of formula how long it will take to transmit all messages succesfully (so without collisions)? Or is the time unknown when starting to transmit?
If (1) is no -> Is it possible to calculate the maximum time of the transmitting? So for example -> 'it'll take max. 10ms before all the messages are transmitted succesfully'.
I hope my questions are clear to you! If not, I'm glad to clearify when needed!
Thanks for your time!
@NickGreen, note that you're almost always on an empty collision domain nowadays. Collisions can only happen on half-duplex links, and if you're on a switch, you're on a full-duplex link. Hubs fell out of use early in the 100 mbit days, and the GigE spec doesn't even allow hubs at all. It's very uncommon to find any hubs in use anymore. – Spiff – 2011-06-07T20:08:34.277
@Spiff, if you're on shared medium, like IEEE 802.11, you're in a collision domain quite often. – Max Ried – 2011-06-07T20:13:00.737
1IEEE 802.11 is CSMA/CA (A = Avoidance), not CSMA/CD (D = Detection), so since he specifically asked about CSMA/CD, I don't think the 802.11 case applies. If it did, your calculations in your Answer would be woefully insufficient for 802.11, because an 802.11 TXOP and the inter-frame timing rules are far more complex than wired Ethernet. – Spiff – 2011-06-07T20:20:12.467