increasing the ethernet MTU greater than 1500 (1502)

Richard A Steenbergen ras at e-gerbil.net
Fri Jan 6 19:53:15 PST 2006


On Fri, Jan 06, 2006 at 06:35:00PM -0800, kamal kc wrote:
> 
> thanks for providing the insight. I would try 
> with GigE next time.
> 
> since it seems a bad option to try MTU larger than
> 1500 in 10/100 Mbps ethernet i tried another option to
> solve my problem.

Also try any number of other $5 10/100 NICs with vlan/mini-jumbo 
capabilities.

> Now i don't add additional header(2 bytes) to
> distinguish 
> the packets that were processed. I rather tried for 
> protocol mapping.
> 
> This is what i did,
> 
> i mapped the protocol (in the protocol field of the ip
> header)
> 
>           0..56 to 138..194 if compressed
>           0..56 to 195..251 if uncompressed 
> 
> with this simple protocol mapping i could only
> compress
> 57 protocol data.
> 
> I guess the protocols 138 to 251 will not be used for 
> couple of years. 
> OR Is there any slighest possibility ????

If you're sure you're not going to deal with fragments, and you're ok with 
violating rfc's and hacking the headers to suit your needs, why not steal 
the id and/or frag offset fields?

-- 
Richard A Steenbergen <ras at e-gerbil.net>       http://www.e-gerbil.net/ras
GPG Key ID: 0xF8B12CBC (7535 7F59 8204 ED1F CC1C 53AF 4C41 5ECA F8B1 2CBC)


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