IP Masq + Checksum Errors - Possible solution?

IP Masq + Checksum Errors - Possible solution?

Post by Iain McWilliam » Thu, 18 Dec 1997 04:00:00

Using IP Masq supplied with RedHat 4.2, any win95 machine on our local
lan would cause TCP/UDP checksum errors when web browsing. The errors
would sometimes be so frequent as to seriously reduce throughput. (Web
pages would tend to stall).

On looking at the IP Masq pages on www.indyramp.com we could see that we
weren't alone in suffering this problem. So I started fiddling, on the
assumption that not everyone was experiencing this problem...

Anyway to cut a long story short I have been able to isolate one option
in the ppp setup that is capable of toggling this problem on/off.

    "Van Jacobson header compression"

With -vj (Disable) in ppp/options we get no checksum errors

With #-vj our ISP negotiates VJ compression and we get approx 8 checksum
errors per minute when browsing.

It would be interesting to see if this works for anyone else seeing
these errors.

Iain McWilliams                          LMP Technical Services Ltd


1. IP masq ftp's hang at 100 percent a possible solution

I was looking for a solution to the problem of ftp's hanging at %100 ot
pretty close.  I came across some things about MTU path discovery
causing some problems for trumpet winsock and Open transport.  So I
check yahoo and there was some talk about it but the link was dead.
I disabled the path discovery on a win95 machine behind the router and
did not get any hangs in a few downloads.

I was just wondering if anyone has found that this solves their problem
so I can stop downloading uneeded things trying to get a hang...
I've followed you, talked to your neighbors, tapped your phone, and even shot
at you to see how you would react.  From my observations I have come to one
irrefutable conclusion: You are Paranoid.  --unknown

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