Ports blocked by cable isp
 

I have just switched over to cable from dsl (today) and am amazed by the speed increase. Went from 600kb/s to over 2mb/s. Its sweet. However, they are much more restrictive. They have port 80 and most all other ports closed. Is there any way of finding out which ports are open or closed or if there is a way to get around this? I have talked to them and they won't tell me and will not open any ports for me. Anyone else deal with this?

chances are, they have ports after 1024 open... *shrug* That's how it was with my old cable provider... gte? adelphia?

they block 80 so u dont house off your computer.

you can do a port scan of 127.0.0.1
scan every port

http://www.petri.co.il/quickly_find_...open_ports.htm

turn firewall off cause it might block some ports also
try this in terminal "netstat -f inet -W"

look for ESTABLISHED connectiong on local host
that'll show you open ports
what happends

have a friend you trust port scan you while you turn off all firewalls, except if you have a router and only want specific ports open.

Don't port scan 127.0.0.1 because that won't tell you the ports the ISP has filtered.

no luck there... any one know how to get around this short of canceling my account and going back to dsl?

I am not sure if you know this, but are the ports being blocked from your cable service ISP or from you cable modem? There has been other threads, where I read that certain cable modems, come with thier own "internal router", usually as Cisco one. And maybe it is configured to block those ports. In that case, you could try one of two things. First, is to try and get a different cable modem from them, one of a different brand. Or you could try to gain access to that router and change the ports that are blocked (don't know how or even if it can be done). Now either of these is only IF its not blocked straight from the ISP. I got two questions. First, did you run that port scan people were talking about above? Were all ports up to 1024 blocked? If you didn't get a chance to run it. I know that grc.com has something called "shields up", which I use regularly, which will check all ports from 1-1024 to see if they are open, closed, or stealth (meaning not even a response). It is meant to help people check if they have security holes, but it could work the other way around, if you stop all your firewall's and the winxp internal firewall if you run that OS. The other question is, what cable company is this!?! Good Luck

G_Lock

also what are you trying to run that its blocking? if you want a webserver then you'll just have to use a different port like 81 and at the end of the url put :81 ie http://x.x.x.x:81 if its an ftp then just try random ports like 81 or 444 and so on.

Im not sure about the whole cable modem blocking the ports, first time I've heard that but I know the cable modem controlls your bandwidth speed which I found out a awhile back *cough*

I'm on Optonline in NY. I don't believe its the cable modem, there is no built in router in it and no programming abilities to it. I have also run port scans and Shields Up but everything was 'stealth' even with all firewalls shut down.

Wile
I ran optonline as well, but I never did any webhosting from my server... I know that they used to block 20,21, & 80... for some reason they stopped blocking 20/21 and I used to host an FTP server...

What are the first two octets of your IP address? (eg first two octets of 12.34.56.78 is 12.34.x.x) Only give us the first two, don't want anyone messing with you....

24.44.xxx.xx

My cable provider runs a nat proxy so unless you pay to get it disabled you will have no way to accept incomming connections to your computer. Might be that way for yours too.

What is funny is that ISPs have to sign an agreement form with varying upstream providers that explicitly states that they are NOT ALLOWED to block ports, protocols, or anything of that nature. This is in fact an extremely common breach of contract with ISPs.

Too many people act indifferently to this.

Can you run your website on a different port? I know that http://stuffs:2003/stuffs looks weird, but you're probably on a dynamic IP anyway with a cable modem, so you already have a nasty URL...

Or you could see if they offer "business" cable modem service which is really just the same thing without the port blocking and give you a higher speed limitation (sometimes they also QOS your packets higher priority on the network). It's usually not too much more expensive, and you get a few static IPs to use.