I’ve been trying to solve a very strange networking problem that I’ve been having with my cable tv boxes.
I’ve managed to do a port capture using port mirroring and wireshark of what is happening
working test - using an old router - WNDR3700
I run the IP Connectivity test on the cable tv box
http://wel-cdn220-is-1.se.fxtvpd.ngcdn.telstra.com/images/Download_test.jpg
apparently this is what it downloads
here is the port capture when it’s working - no issues
http://www.megafileupload.com/97vX/portcapturefoxtelworking.pcapng
failing test - using new router - mikrotik RB951G-2HnD
I run the IP Connectivity test on the IQ2 box
http://wel-cdn220-is-1.se.fxtvpd.ngcdn.telstra.com/images/Download_test.jpg
again it grabs this file
here is the port capture when it’s failing - lots of DUP ACK and spurious retransmissions.
http://www.megafileupload.com/97uX/portcapturefoxtelfailing.pcapng
for reasons that I don’t understand, it starts getting DUP ACK packets around entry #184, then it gets stuck around #242 with a heap of DUP ACK packets before the connection terminates at #397
I would really like some help with this.