[H-GEN] PPP problems

Michael Anthon mca at tams.com.au
Tue Jan 18 23:12:03 EST 2000


[ Humbug *General* list - semi-serious discussions about Humbug and ]
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I've never really understood this statement when it comes to modern modems.
Pretty much most modem connections established these days would (I guess..
no hard facts to support me here) be using error correction on the modem
connection itself.  In this situation, setting the MTU/MRU to a lower value
has only one effect as far as I can tell and that is to increase the
overhead on the link by generating more packets.  

I understand that on older modems where error correction is not provided on
the link, then having a smaller MTU/MRU will result in less retransmitted
data when a packet gets corrupted.  

There may well be a problem however when it comes to the serial interface on
the PC side.  Perhaps the buffer is not being emptied fast enough and then a
larger packet may have this the side effect of causing framing errors....

That said, even if there are framing errors occurring, then I doubt if it
would cause a file transfer to be aborted.

Cheers
Michael Anthon

<snip> 
> oooooooh no, that's 'orrible. depending on the connection 
> speed of course,
> but your MRU should be around the 572 mark for 36k
> 
<snip>

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