Re: Was change to ip_push_pending_frames intended to breakudp (more specifically, WCCP?)

From: Vlad Yasevich
Date: Mon May 22 2006 - 14:54:05 EST

On Mon, 2006-05-22 at 11:48 -0700, Rick Jones wrote:
> > IP id is set to 0 on unconnected sockets when the DF bit is set (path
> > mtu discovery is enabled). Try issuing a connect() in your application
> > and see if the ids are increasing again.
> ID of zero again? I thought that went away years ago? Anyway, given
> the number of "helpful" devices out there willing to clear the DF bit,
> fragment and forward, perhaps always setting the IP ID to 0, even if DF
> is set, isn't such a good idea?

Hey... I just report what I find... ;)

I had to look at this code a bit for some SCTP cases as well and this
seems to be how it works. Here a comment from the code for the case
of the DF bit being set
/* This is only to work around buggy Windows95/2000
* VJ compression implementations. If the ID field
* does not change, they drop every other packet in
* a TCP stream using header compression.


> rick jones

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