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[ss@cse.unsw.edu.au: Re: [disconnect@unsw.edu.au: Re: network problem]]

Hi,
	Please see my problem forwared below. Is there anyway to let linux
	to reassemble the packet?

	I have fixed my problem by forcing ppp to use a smaller mru & mtu 
	size. But, is this the standard way to do it??

	Thanks.

shao.

-- 
____________________________________________________________________________
Shao Zhang - Running Debian 2.1  ___ _               _____
Department of Communications    / __| |_  __ _ ___  |_  / |_  __ _ _ _  __ _ 
University of New South Wales   \__ \ ' \/ _` / _ \  / /| ' \/ _` | ' \/ _` |
Sydney, Australia               |___/_||_\__,_\___/ /___|_||_\__,_|_||_\__, |
Email: shao@cia.com.au                                                  |___/ 
_____________________________________________________________________________
--- Begin Message --- 
  Shao,

  Has cse changed the mtu size? No.

  1500 is the standard size for ethernet. The problem is that the 1500
  should include header information. linux should allow for the header
  size and request a smaller "maximum segment size" when it starts
  a transaction.

  Our web server doesn't have a problem with the larger segment size
  (being on fddi with a much larger mtu), but the packets end up being
  fragmented. We think your machine then has a problem reassembling
  the fragments. Thus the fix to change the mtu should avoid the
  fragmentation.

  You may not have the problem with other ISP's as they may compensate
  by forcing a smaller mtu.

Cheers,
Tanya (ss for today)

> > > >   -----Our original reply to your problem----------------------------
> > > > 
> > > >   Are you using linux? If so, your problem may be because the packets
> > > >   for your web transactions are getting fragmented and (perhaps)
> > > >   your machine is not reassembling the fragmented packets.
> > > >   [By default linux requests a too-large maximum segment size, which
> > > >   our web server is happy to comply with but which causes packets
> > > >   to be fragmented]
> > > > 
> > > >   Try this for a fix: see if you can configure pppd to request smaller
> > > >   packets. To do this set up a .ppprc file in your home directory
> > > >   and put
> > > >         mtu 1000 mru 1000
> > > > 
> > > >   (to decrease the maximum transmit/receive unit sizes)
> > > >   --------------------------------------------------------------------
> > > > 
> > > > Cheers,
> > > > Tanya (ss for today)
> > > >   
> > > >

--- End Message ---
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