> From: discuss-bounces+blu=nedharvey....@blu.org [mailto:discuss-
> bounces+blu=nedharvey....@blu.org] On Behalf Of Tom Metro
> 
> Comcast Business cable Internet

I have used Comcast Business, and I'm the same as you - I would love to avoid 
using any of those companies ever again, but *especially* comcast, based on 
this experience.

We had a satellite office, and we had Comcast Business cable in there, as well 
as a T1.  We needed to ssh from the home office into the firewall of the 
satellite office, but it wasn't working.  We traced it down:  If you try to 
connect to port 22 of the external IP of the comcast business IP address, then 
the packet never reaches the destination.  But if you ssh to the T1 IP address, 
traffic gets through just fine.  This proved that comcast was blocking inbound 
port 22, and *not* a failure of the sending side to send the traffic.  We 
hooked up packet sniffers on both the sending side, and each of the receiving 
sides, and saw the packets go out from the home office, destined to each the 
comcast IP and the T1 IP.  We saw the packets arrive on the T1, but not 
comcast.  Other types of traffic worked fine.  It was only port 22 that was 
blocked.  I seem to recall we couldn't change the ssh listen port, because it 
was a PIX or something, but that particular detail is cloudy now.  (T
 his happened about 5 years ago.)  

Could not possibly be any more definitive proof that comcast was blocking port 
22.

Comcast denied it despite hours on the phone with them.  Problem was never 
resolved.
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