|
North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: Ethernet NAPs (was Re: Miami ...)
At 10:18 23/08/01, John Kristoff wrote:
>Certainly. In a nutshell, it might be best to take steps to avoid
>fragmentation elsewhere in the network. Perhaps a rule of thumb that
>should be stressed is to use jumbo frames if you know for sure the other
>end system(s) support it, otherwise default to 1500.
Or just use Path MTU Discovery.
For IP traffic that is traversing more than one layer-2 network,
the variety in network technologies (e.g. ATM, SMDS, POS, Radio,
Satellite, other) means that even ~1500 byte IP frames might not
always work end-to-end. For example, I know of several commercial
IP/SATCOM systems that have an MTU of 576 bytes.
Many ISPs, not all, seem to try to engineer an end-to-end MTU
of 4470 (that number chosen for historical reasons relating to FDDI).
Some ISPs use a smaller MTU number and some use a higher MTU number.
Ran
[email protected]
|