[pptp-server] Re: [pptp-server] GRE out of order again...

[David Luyer]

> Dont really understand why its a problem.... the only socket that shows up
> in netstat is the raw-socket that pptpd makes. Could it be a problem with my
> NT VPN 
> that keeps sending wrong packets?

No, it will be sending them in the correct order I'd expect, there are 
sometimes issues with packet re-ordering on heavily loaded interfaces but
it should be rare.

> Or could it be the Internet that's dropping some of the packets?

It's not dropped packets, but out of order ones.

Basically, the problem is most likely related to having multiple paths or
multilink connections between where you are connecting from and to.   The
packets which turn up after the packet which is sequenced after them must
be dropped (since PPP depends on only getting frames in order, it's ok to
drop some but not OK to send them out of order).

ie:
  packet 1 arrives, we send it to pppd
  packet 3 arrives, we send it to pppd
  packet 2 arrives, we must drop packet 2