My ISP Has Closed Nearly All Of My Ports

[636_Castle]

I'm getting really fed up with my ISP (Comcast) right now. I've been having multiplayer connectivity issues lately, and decided to scan my ports to make sure they were open. What I found was insane.

 

 

 

Only 4 ports of mine are open. I'm connected through a router, but I have my router set to open all ports 0-65535, and I have my router's DHCP IP it assigned me (192.168.1.100) set as a DMZ, so port forwarding should not matter.

 

 

When I use probemyports service on my external IP assigned by my ISP, I see similar results.

[Steel Jaw]

I had read that the fascist and bloated DHS agency in the US was asking this of ISPs for "security".

 

You watch: next will a law forbidding the use of routing devices by the public.

[636_Castle]

Here's a screenshot of my external IP provided by Comcast being scanned. The ports that are supposedly "open" according to Comcast are actually stealth ports, the rest are closed. (Green=stealth, blue=closed.)

 

Edited October 29, 2010 by 636_Castle

[Steel Jaw]

Dude that's just wrong, have you called them yet?

[GGTharos]

... so you scanned your PC on your internal network and all those ports are closed?

 

I'm getting really fed up with my ISP (Comcast) right now. I've been having multiplayer connectivity issues lately, and decided to scan my ports to make sure they were open. What I found was insane.

 

 

 

Only 4 ports of mine are open. I'm connected through a router, but I have my router set to open all ports 0-65535, and I have my router's DHCP IP it assigned me (192.168.1.100) set as a DMZ, so port forwarding should not matter.

 

 

When I use probemyports service on my external IP assigned by my ISP, I see similar results.

[Panzertard]

There's nothing wrong. ;)

You scanned using internal-ip ranges, which means it's not your ISP.

Those IP adresses are not routed through internet.

 

You scanned another PC on your network, and:

- It answered on all the relevant ports for a standard PC.

- It doesn't have any other services, so it cannot answer on port where there are no services answering.

Ex: Wanted to check port TCP 134? It needs to have a service answering on port 134 TCP - if no service have an active listener on 134, nothing will answer. Hence it's 'closed'.

 

Now, if you need to test - you need to check:

- Set up your own PC/server - and have relevant services on the ports you want to check.

- Scan from "the other side", ex another internet address, ex. from a buddies PC.

 

Now - when you do that, keep in mind - some ISP may actually check for someone doing portscans and block this IP. They may also choose to press charges if you haven't warned all involved parties about the portscan, since it can be illegal to do so.

 

And yet again, your postscan may not be successful at all if the PC you borrow is not set up for this. Or if some router/firewall in between is not configured properly for such a test.

 

PS, a final scare: If you DID have a PC that answered on all ports over internet I would have been VERY worried. It's be open for attack, and most certainly - it would have been compromised. Go pay your bills via it, and you're guaranteed to see someone pulling a few bucks out of your account now & then.

Edited October 29, 2010 by Panzertard

[Panzertard]

If you want to check for something specific - like "why cannot people connect to my FC2 server" or "why cannot I connect to this / that DCS server", I can give you a few good tips to check. ;)

[topdog]

I use Shields Up service to check my firewall setups from the outside (see image).

 

Closed or stealthed ports aren't a bad thing. If mine were NOT stealthed, THEN I'd be worried/annoyed. Mine can be stealthed and yet I have no issues with connecting outward to anything.

 

If you have a port open on your pc, it means you are (or intend to) hosting software there that outsiders are allowed to get into your network to connect to.

 

Otherwise, ports will open as needed and close as needed.

 

If you host a server, and the port that host is listening on is still closed/stealthed to the outside world, then that will be a problem and prevent other users from connecting to your server.

 

That, however, is almost always a router/firewall config issue within your own broadband modem (that you have the power to reconfigure) or Windows' own firewall.

 

Routers will often refer to the capability of allowing you to run a server for others to connect to as part of their port forwarding feature, and when used to point a router's port to a machine ip/port on your own network, then they will present the port in an open state to outsiders.

Edited October 29, 2010 by topdog