Re: Protocol Benchmarking (with Accept examples - long)

Henning G. Schulzrinne (hgs@research.att.com)
Wed, 2 Feb 94 20:39:21 EST

To add some very basic performance numbers:
- each cross-country round-trip will take a delay of 60 ms or more
(example: ping times from here on the East coast to the West coast
from and to well-connected sites are on the order of 100 ms).

- a 1 KByte packet will take 8 ms of transmission time on each
1 Mb/s (T1) hop, without any queueing. Take an example:

ping (round-trip) time from portal.research.att.com to beta.xerox.com:
56 bytes: about 100 ms
1000 bytes: about 190 ms

The arithmetic is thus fairly straightforward: if you need more than
two even tiny packets (on average) to do the job of one monster
packet, you lose. The calculation gets worse with high-latency
firewalls or transatlantic connections in the middle. For slow
links, clearly, things look somewhat different; there is no
universally best strategy.

Henning Schulzrinne