Newcomer

Is port 80 blocked from my phone to my home?

I think something is blocking port 80 from

 

Source      107.77.xxx.xxx (my mobile phone on AT&T)
Destination  76.88.xxx.xxx (my web server at home on TWC)

 

The result I get on the phone is there is no response and eventual timeout.
The website is up and I can access it just fine from a browser on a PC from anywhere else I try.

When troubleshooting, I run tcpdump on port 80 on my server and no traffic is detected.

Some testing info...

  • The result is the same using Chrome, FireFox, and wget from my phone.
  • The result is the same from another phone using the same SIM card.
  • The result is the same using a domain name or the IP address of the server.
  • The IP address of the phone varies sometimes, the last octet changes, the result is the same.
  • I have re-installed FireFox and wget, cleared all cache and data and the result is the same.
  • I have no firewall rules set up on my server; iptables -L shows all ACCEPT.
  • I have no content filtering on my router and have port forwarding enabled for port 80.

However, from the *same* phone...

  • I am able to connect using HTTP over an alternate port, 8349.
  • I am able to connect using SSH over port 22.
  • I am able to connect to all other web servers I try.
  • I am able to connect to another web server at TWC (70.95.xxx.xxx)
  • I am able to connect over a wi-fi network.

Also...

  • I am able to connect from other people's phones using Sprint's, T-Mobile's, and Verizon's mobile network.
  • I am able to connect from another person's phone using AT&T at 166.137.xxx.xxx.

The problem seems pretty isolated to my phone service and my web server and port 80.

I have not tried forcing my cable modem to get a new IP address. It was last changed March 2016.

How can I find what is blocking access?

2 REPLIES
Expert

Re: Is port 80 blocked from my phone to my home?

Don't use port 80, it's garbage to doi so and is a huge security risk as all hackers go after it first.

 Next, You're running a server on TWC residential service?

Probably a violation of the contract, lol.

 

Highlighted
Established Sharer

Re: Is port 80 blocked from my phone to my home?

[ Edited ]

Nobody with any internet experience would leave port 80 open and unfiltered.  It's the most popular target for malware delivery to folks who don't turn on their router firewalls.  Common substitute ports which have to be specifically opened for use are 1080, 2080, 8080, and 10080. 

Also, since AT&T and TWC share some fiber transport hops, it's possible that port 80 is blocked at the IXP crossover points.