I have ran into two sites I have to port forward for example port 6900 to let a client software connect to a video server behind modem and router..

both are using DSL ISP

It's a simple netgear router /port forward/add custom/specifiy your port 6900 /TCP+UDP to lan ip of 192.168.1.23 which is video server lan ip and add it to the list..

If i do http://192.168.1.23:6900 it works fine..from LAN
from WAN http://64.25.xx.xx:6900 nothing...

Firewall is off

I contact the ISP and they said nothing is block from the modem and ISP is wide open..

If i scan the port only port 80 is open

I ended up having to setup Hamanchi VPN to get it to work


A Client with Cable ISP i don't recall having any problem with...Its almost always a client with DSL ISP..

I'm always wonder if these ISP actually block some ports.....then tell u it's not