[philm]

I travel a lot with my trusty MacBook and a couple of things happen occasionally which I can't really explain and I am sure that the brains on the MacNN forums will help me out.

Query 1: For example, last night I got into my hotel in Antwerp and the room had wireless access. I selected the SSID in the Airport menu icon, and immediately Skype (which was already open) connected up and I saw my contacts list. In other words, I had an internet connection. However, my web browser (Firefox) did not allow me to access web pages until I had gone through the usual ritual of being forced to the wireless registration page, add my room number etc.

So, this suggests that I had an internet connection which allowed some ports through (the Skype ones, whatever they are) but not (presumably) the more common ports for web access and e-mail (80, 110, 25 etc). Did they just 'forget' about the Skype ports? Why not block all ports until I have a valid connection?

Query 2: Quite often, in airports and hotels under the Airport menu, I see 'Free WiFi access' in the Computer-to-Computer part of the menu. Sometimes I try and connect to it, but it always fails. What is going on here?

Cheers.

[nonhuman]

It's entirely possible that they just didn't block the Skype ports. It's pretty common for them to basically just block the most common ports for web and email and leave everything else open. When I was in Honolulu last year we were able to get free internet through the hotel's pay wireless by just setting up an SSH tunnel to a Squid proxy we had the address for and tunnelling all our web and email traffic through that.

[mduell]

Originally Posted by philm 

Query 2: Quite often, in airports and hotels under the Airport menu, I see 'Free WiFi access' in the Computer-to-Computer part of the menu. Sometimes I try and connect to it, but it always fails. What is going on here?

I see this just about everywhere I go. Usually "Free Public Wifi" but the text sometimes varies. I assume it's a virus or otherwise hijacked Windows machines trying to infect the rest of the world.

[shifuimam]

Not to mention that a "computer-to-computer" network is a mesh/peer-to-peer network. If none of the computers have a connection to an actual network that's on the Internet, a mesh network will only allow computers to share things between each other - like a home network without Internet access.

The Skype-on-wireless thing is probably what others said - ports 80 and 21 are blocked, but most everything else isn't.