Subject: Re: 802.1Q & ETHER_MAX_LEN
To: None <itojun@iijlab.net>
From: Anders Magnusson <ragge@ludd.luth.se>
List: tech-net
Date: 10/02/2000 02:39:34
> 
> >> 	the problems are:
> >> 	- we have two ways to do VLAN: decreasing MTU or using bigger L2 frame
> >802.3ac specifies that the total ethernet packet length can be up to
> >1522 bytes so that switches don't have to fragment packets when
> >converting between VLAN/non-VLAN networks. If we are going to handle
> >VLAN we must obey this rule.
> 
> 	but for legacy ethernet cards, it may not be possible...
> 	(or are you suggesting that we shouldn't use decreased MTU?)
> 
If a ethernet card can't handle 1522-byte packets, then it probably
will not work in a VLAN environment.
Does it actually exist cards that can't handle packets >1518 bytes??

-- Ragge