The specs says ISP F-Secure as anti-virus which means the AV works together with Windows Firewall. I use it too.
Anyway, my point in all of this is that if you're behind a router that hasn't opened anything to the outside, then it shouldn't matter what ports are open on the computer or how the computers firewall is configured. The router should block
everything coming from the outside, in firewall terms called inbound connections. This way the router will protect all devices on the LAN(local area network).
The opposite of an inbound connection is outbound connection, meaning when your computer was the device who initialized the connection to the outside. This means basically every connection made from the computer: browsing, email, programs connecting and checking for updates etc. The router uses NAT -
Network Address Translation to keep track of which device on the LAN should receive the reply.
If you use your browser to go to a website you create an outbound connection and the router waits for the reply. The reply is not an inbound connection, it's a reply to the outbound.
But when you use
ShieldsUp it's not the same because only the reply in the browser is a reply from the outbound connection, while the actual ShieldsUp test is triggered from different IPs, otherwise the test wouldn't work. It needs to test connections from an IP that you're not already connected with in the browser. Therefor making it inbound connections to your router.
This is mentioned at the top of ShieldsUp page:
you should expect to see entries from this site's probing IP addresses: 4.79.142.192 -thru- 4.79.142.207
Or to put it this way:
- For an outbound connection your computer knows who or what will respond to it, because it requested a specific resource on the Internet, an IP and port.
- While an inbound connection can be triggered by anything on the Internet
Hope that helps someone :)