I learnt why CSMA/CD cannot be used in wireless protocols here. Here is what the answer says:
Wireless transceivers can't send and receive on the same channel at the same time, so they can't detect collisions. This is due to the fact that there's an incredible difference between send power (generally around 100mw) and receive sensitivity (commonly around 0.01 to 0.0001mw). The sending would cover up any possible chance of receiving a foreign signal, no chance of "Collision Detection". For this reason Collision Avoidance with Control Messages is necessary.
On most wired networks the (like Ethernet) the voltage is around 1 to 2.5v; both sending and receiving are roughly the same voltage. So if you're sending a 2.5v signal, and someone else collides with a -2.5v signal, the "Detection" parts will see a signal somewhere around 0v and know a collision occurred.
I have following doubts:
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Can we use CSMA/CA (Carrier Sense Multiple Access / Collision Avoidance) on wired networks?
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If yes, then is their any protocol to use CSMA/CA on wired network?
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If no, why?
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I was guessing, it must be technically possible to use CSMA/CA on wired network, but most of them use CSMA/CD, because sending signal and then striving to detect any collision is faster than first ensuring collision will not occur and then sending signal. I am correct with this? Or is there any other reason?
PS: I was trying to add following tags: csma, error-control, link-layer, data-link-layer. But I dont have enough reputation points to create new tags. Please add tags as desired.
Best Answer
In theory, yes.
Nothing in use today
Sounds reasonable to me. but to be sure, you'd have to ask the people who invented Ethernet (Bob Metcalfe) that question. Remember that Ethernet and other protocols went through several stages of development and refinement before becoming what it is today.