Every Port Test Fails

127.0.0.1 is your computer meaning all you are doing using telnet to telnet yourself, which has nothing to do with comcast its all happening on one computer. In order to use telnet you must have a telnet server, telnet is looking at your computer which does not have thus running therefore it will give you an error.

You have to open the port on your Router. YOu can do this by typing in 192.168.1.1 in your web browser (Safari, Firefox etc) I believe it could also be 192.168.0.1 I am not sure what D-Link uses

 

He knows this. If you read the first sentence he is trying to telnet him self to see what ports are open on his end.

That being said, yes port 80 is the port used for websites.. But it shouldn't be open on your end unless you are running a web-server. Just because you can access the internet means nothing.

 

You appear to be very confused. The command you typed is attempting to connect to a web server running on your local computer. It would only work if you've enabled Web Sharing in your System Preferences.

That has nothing at all to do with your ability to visit other people's web sites out on the internet, which is outbound traffic and your router almost certainly allows any outbound traffic you request unrestricted.

If you, for example, typed the command

Code:

telnet forums.macrumors.com 80

you'll find that it does work. (well, for sufficiently small values of "work") It'll just connect and then expect you to talk http to it. Nothing exciting or dramatic.

Your failed telnet localhost 80 command just tells you that you're not running a web browser on your Mac. It doesn't necessarily mean that your router is blocking inbound traffic on port 80.

 

A really good test for your ports security is this website by Steve Gibson. I've tested my ports and it shows stealth as if there is no computer on those ports that I tested. Give it a try at this website using "shields up"

http://www.grc.com/intro.htm