> > It's not simply eight bits per byte for ethernet packets, it's more > complicated than that and you're not taking into account collisions. > > > Im a bit confused now... > > so how... > > I mean > > a Byte is 8 bits, a bit being either 1 or 0... I thought that was a > fundemental of computer science. > > Am I wrong? In a typical technical response, yes and not.
There are 8 bits in a byte (well an 8 bit byte anyway), an ethernet packet usually* holds 1500 bytes. However, the packet has to know where it's going, so that uses some extra data, and where it's come from, and have a checksum, to it can tell if it's been corrupted in transit. Then there is the problem that networks aren't perfect and problems (collisions) do occur, and packets need to retransmitted, a packet retransmitted is a packet lost... So while a 100 MEGA Bit/Second link can in theory send 12.5 Mega bytes/Sec, in practice you lose up to 30% of the throughput in overheads. So you're looking at around 9 MegaBytes/sec. With poor wiring and non-switching hubs you can lose even more... Wireless network lose even more of the headline rate, as the bandwidth shared among the clients... It gets very complicated very quickly, but if you are interested, have a google for the ISO 7 Layer model... :) -- ubuntu-uk@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-uk https://wiki.ubuntu.org/UKTeam/
