[lwip-users] Re: [lwip] dependeny of MSS on MTU

[Adam Dunkels]

Hi!

On Fri, 2002-07-26 at 11:17, amol patel wrote:
>    In lwip stack we r using bit stuffing mechanism for escape
> sequences. In the worst case if we have to bit stuff all the
> characters of a packet then the size of the resulting packet will be
> double of the original packet which we must be able to send using the
> datalink layer. Now if the  MSS * 2 > MTU we have to go for IP
> fragmentation for which we have not included the code in lwip.
> Is this implies that the size of the MSS should be 1/2 of the MTU to
> avoid a situation like this?

Of course, this depends a lot on how your implementation works, but in
general the TCP MSS and the MTU wouldn't be affected by escape sequences
used when transmitting the bits on the wire (the escape sequences
usually is decoded when the data arrives and not when it is in the
buffer). 
 
/adam
-- 
Adam Dunkels <address@hidden>
http://www.dunkels.com/adam/

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