IRC Net Bandwidth (was IRC and Security)

[Richard Alan Schafer]

In article <703 at seqp4.UUCP>, jdarcy at seqp4.ORG (Jeffrey D'Arcy) writes:
|> brnstnd at kramden.acf.nyu.edu (Dan Bernstein) writes:
|> >But it's the packets that cost. A 2-byte packet costs almost as much as
|> >a 500-byte packet.
|> 
|> Yeah, right.  On an Ethernet, you have a 14-byte Ethernet header, 20-byte
|> IP header, 20-byte TCP header, a couple of trailers...all told less than
|> 60 bytes, and I can't imagine other data links are that much worse.  That
|> would seem to make a 500-byte packet about nine times as costly as a 2-byte
|> packet in terms of transmission time.  Certainly there are per-packet costs
|> regardless of the packet length, but not enough to make your statement even
|> nearly true.

True, if all you're considering is the actual number of bytes send down the
pipe.  But if you consider the effect on anything that has to route the 
packet, everything I've seen suggests that the handling of the packet
headers, etc., is much more of a load than the actual size of the data
in the packet itself.  I.e., if decoding the headers in a 1500 byte
Ethernet packet takes up more time than actually sending the data portion
of the packet, then the size of the data is not necessarily relevant.