Re: Fw: [lwip-users] Dropped Packets on PC receiver with lwip 1.1.0Transmitter

[Kieran Mansley]

On Thu, 2007-03-29 at 11:00 -0500, Paul Butler wrote:

> I've attached the complete log in wireshark (ethereal) pcap format, please
> let me know if you see anything interesting.  If you think can get it to
> post to the list and get some more eyes on it, I'd appreciate it.

I've had a quick look and can't see anything wrong with the packets that
are getting ignored.  

However, if Window's thought they had a bad checksum, it would not send
an ACK as it wouldn't trust the packet enough to work out where to send
the ACK to.  However ethereal things these packets checksum OK, and
given that you've captured this at the Window's end of the connection,
the scope for it going wrong from this point is small.

If you were using linux at this point I'd suggest looking at the network
stack statistics using "netstat -s" while these packets are coming in -
it should tell you why it is rejecting them.  I'm not sure how to
achieve something similar on windows, but I guess it probably does keep
track of how many packets were dropped due to bad checksums etc, and you
could watch those counters to find out why it's dropping them.

Kieran