Cut through and Half duplex

Bonsoir,

A mon avis:

Since in principle half duplex makes the individual bits available "simultaneously" to all hosts attached to the single Ethernet, there is no "store and forward" going on at all. It's always cut-through, at least in principle. In fact, half duplex can be considered bit-by-bit cut-through. Unless you use half-duplex just to get access to a switch port, which of course is an option.

Cut-through, IMO, is a concept that applies only to switched Ethernet catenets, where switches look at just the frame overhead fields before beginning to forward the frame. (And it only works if the links are all operating at the same speed.)

Albert

Bonjour Albert,

Thanks for these useful words, it makes me thinking more deeply (euh... I try, I try...).

You're right, the CSMA/CD algorithm is like that. The MAC frame is sent in a bit-serial form, the collision is observed after each bit transmitted.

I like this statement

Face to a collision domain, a switch port needs to be in half-duplex.

Best regards, Michelot