I understand the principle of collision domains and how they are issues in hubs. I also get how switches are actually creating its own collision domain on each port. Therefore Port to Port communication creates a collision domain and takes care of collisions. It is all find and dandy here. What about the situation when I have two switches -- let's assume 48 ports each, daisy-chained together? What will happen when 48 ports on switch1 will receive transmissions at the same time and need to resend it to 48 ports on switch2? I assume that all 48 signals should be transferred over the SINGLE daisy-chain link. Will that one link introduce ONE collision domain for all 48 ports? I logically assume that it won't, but I don't understand how.
If all 48 ports attempt to TX to the same "port" at the same time, it will most likely overrun the internal buffer space and "no buffer" (in cisco circles) drop the frame(s). As this is all at layer-2, no error is communicated to anyone; the frames just don't get there.
(This is all part of the store-and-forward processing of switches.)
Back all the way up to the premise of the question. A collision, as it were, can only happen in a half duplex situation when "the wire" is common to both receive and transmit, and both sides try to transmit at once making the output from the wire unusable. So, even between two PCs attached to the same switch that communicate with each other, the two ports are not a collision domain as long as both hosts are linked at full duplex. If two hosts do happen to be both half duplex, then there is a collision domain between the switch and the host, which will be arbitrated by the efficacy of the carrier sense logic of each.