If you go to www.portforward.com on the left hand side you put in your modem/router make then model it will then tell you step by step how to port forward and where to get the values you need to enter to open the ports correctly.
I did the search for you, and if i correctly picked the product you wanted to portfward for (PSVita) heres the instructions:
Seems you require a static IP to port forward on the Cisco DPC3825, according to the instructions.
You would have to look into the setting son the PS3 and Vita.. in the network connection settings section, there should be a way to MANUALY enter your IP information.
Easiest way to get some of it, is to go to a PC, go to the run window, and type in CMD and then run it.
It will bring up a dos box.
Then here, type ipconfig /all
THe things you want to write down are, the subnet (likely 255.255.255.0)
The gateway (likely 192.168.0.1)
and the DNS servers.
Then on your device, you want to enter that information there... as well as then picking an IP address, similar to what was listed in the IP config.
Something like 192.168.0.200
I am trying to port forward (RealVNC), went through the portforwarding site, followed all the instructions, but nothing.
I tried turning off my firewall and AVG, but still nothing. Canyouseeme shows all my ports are closed (connection timeout).
When I use another wireless internet, I can port just fine. So it must be my settings.
I am trying to remote connect to my work server. When I bring my laptop to work, I can ssh tunnel into the server and use RealVNC viewer to create a workspace. When I bring my laptop home, I can no longer connect to the server through RealVNC.
I can still connect to the server via command prompt. Just not through RealVNC.