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How to test ports on my local computer and the internet?

garryshape asked
Is there a way I can test a variety of ports on my local computer. Whine a firewall? When I go to port testing sites it just scans my external IP but I’m wanting to see if my computer and a corresponding server are capable of communicating over a port with my firewall in between.
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Distinguished Expert 2017
Pleas clarify.

There are online scanners that will scan your IP wan side.
Internal scan can be done by nmap.

You can not scan an internal system from an external source.
HuaMin ChenProblem resolver
You can create Inbound/Outbound rule on TCP ports of Windows OS.


This KB tells me ephemeral ports need to be opened https://newvoicemedia.atlassian.net/wiki/spaces/DP/pages/100697150/Technical+prerequisites?utm_source=share&utm_medium=ios_app&utm_name=iossmf.    For their app to work. But I do not know if that is firewall level or client level and can’t know how to test.
Top Expert 2016
it will be both at your device firewall AND you will port forward those ip addresses to your device ip address at your router/network firewall
Distinguished Expert 2017
As David noted. Commonly you have to open a path along the way.
computer to LAN windows firewall

Not sure it applies to you.

Do you whitelist on your external firewall where and from where you can get ........

The info in the firewall section deals with authorizing outbound/inbond....

You should provide additional information on what issues you are running into.
it might be easier to solve a problem that look at specs and guidance without a point of reference as to what needs to be fixed/resolved.
David FavorFractional CTO
Distinguished Expert 2018
Use https://nmap.org/book/inst-windows.html for this type of testing.


Here is a link to test WebRTC connectivity: https://test.webrtc.org/