ISP port blocking practice

Sat Oct 24 15:41:33 UTC 2009

Chris Boyd wrote:
>
>
> Once it's set up correctly we've found customers really like it since 
> their email "just works" in most places. 

Earlier this week I had an experience at a San Jose[1] Public Library, 
where they blocked ports 995, 587, 465, and 119.  None of my mail 
services (or usenet service) worked, except for the news server I use 
that runs on port 443 (heh) and my webmail backup.  Using gmail/webmail 
I sent an email to the tech admin, and they opened up those ports the 
next day.

This is the first time I've had problems with using these ports - in 
other cases it does "just work" as expected.  I was rather stunned to 
run into this at a public library.  Usually librarians are major 
defenders of free speech and fight vigorously against censoring, 
blocking, and filtering of any type on library computers and networks.  
My guess is that none of the librarians *knew* that the IT department 
had setup these blocks.  I'll have a chat with them the next time I drop in.

jc

[1] San Jose is the 3rd largest city in California, 10th largest city in 
the US and the center of Silicon Valley - I had expected a higher level 
of IT clue than I found.