Subject: Re: IEEE802.3 support ??
To: Shashi Mara <>
From: Justin C. Walker <>
List: tech-net
Date: 02/18/1999 18:01:28
I believe that 802.2 addressing is in fact what is used for 802.3,  
so it is "the same" for all IEEE media layers (for some definition of  
the term).  Is there something specific that is lacking in this  

Ethernet V2 and 802.2 do indeed coexist on the same wire.  The two  
bytes following the source and destination are treated as a packet  
length field for 802.2, if smaller than the Ethernet MTU (1514), and  
as a protocol id for Ethernet V2 if larger than the MTU.

Probably, today, it's anyone's guess.  IP is almost exclusively V2  
on ethernet (except for some legacy gear from HP and compatible  
implementations).  AppleTalk uses 802.2 exclusively.  Then there's  
IPX, which, as I understand it, can use any of a handful of  
mechanisms from V2, 802.2 (with and without SNAP headers, ...).  I'd  
expect that IP is generally the lion's share, but it really depends  
on the installation.



From: Shashi Mara <>
Date: 1999-02-18 16:18:59 -0800
Subject: IEEE802.3 support ??
Organization: Shashi Mara


I am new to netbsd and have some questions for the network gurus.
How come there is no support for IEEE802.3 in netbsd. I was looking at
the if_ethersubr.c code. We already have support for 802.2 LLC (used for
NETATALK, ISO..). I was thinking it should  be quite easy to add the
802.3 MAC encapsulation.

1. Am I missing something ?
2. Can Ethernet(V2) and 802.3 coexist on the same subnet ?
3. Does any body know approximate % of V2  vs  802.3 users "out there" ?

Shashi Peter Mara,

Justin C. Walker, Curmudgeon-At-Large *
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