Cable Modem / Router / Wireless

[Matt Graham]

On Tuesday 17 July 2007 09:30, after a long battle with technology, 
Shawn Badger wrote:
> On 7/17/07, Michael Sammartano <volinaz at cox.net> wrote:
> > Since when?? I have been running sshd on many boxes at home for
> > many years. As far as SMTP service on port 25 and other providers,
> > just set up the email client to use another port for SMTP, whats
> > the big deal?

This doesn't jive with the accounts of another PLUG poster about a month 
ago, who said he was running sshd on port 22 for a while, then had it 
blocked, then ran sshd on another port, then had it blocked, etcetera.  
His account also said that they do some form of (stateful packet 
inspection?) and start blocking ports if they see something like this:

Random machine:  12345 > 22 SYN -> Cox machine
Cox machine:  22 > 12345 SYN ACK -> Random machine
Random machine:  12345 > 22 ACK -> Cox machine
[normal TCP traffic over those ports]

...whether this is true for *every* Cox user or not, I don't know.  They 
may have different policies in different geographical areas, or 
something.  Or there's a traffic limit before they start blocking.

For SMTP, the SMTP server also has to listen on a different port.  SMTP 
servers that are run by clueless people or administratively paralyzed 
people may not be doing that.  

> I would also have to chime in and say that I have been using sshd for
> some time with Cox. They only block what a vast majority of the
> people consider the Internet from running as a service on the home
> connections (SMTP and HTTP).

Since the PHBs have apparently decided to use MSexchange for the new 
mailswerver, against my objections, I've got to have an SMTP server 
that I know will work and keep working accessible.  Nothing 
high-traffic, just a backup for when the Exchange machine dies 
horribly.

-- 
   "Dreams?  Best leave dreams to those that can afford them."
   --Aunt Cordelia, _Wizard and Glass_, Stephen King
There is no Darkness in Eternity/But only Light too dim for us to see