1

When travelling everyone has to use structural wireless networks (managed by airports, hotels, museums, restaurants…).

Some of these only open (80|443)/tcp/ip once you have provided an E-mail or simply put a check mark in front of an I agree button at the end of one page of conditions of use.

But before this web ports opening, a basic tcpdump showed me a terrific amount of traffic (for example waiting in many international airports): ARP, STP, netbios, VNC, ARD…

Beside tcpdump is there any way for a standard user or for a network aware one to evaluate how dirty water is any free wireless network?

This question stands both for before activating the web ports opening, and after this opening.

  • 1
    I believe that by "When travelling everyone has to use wireless networks" you mean other people's WiFis. This is not true. You could purchase global 4G service and use only a single provider and their partners if you prefer. – Neil Smithline Mar 1 '16 at 22:28
  • I didn't mean "other people's Wi-Fi networks" but rather structural Wi-Fi networks made available in airports, hotels… I clarified my OQ. – dan Mar 2 '16 at 9:19
2

The only sensible way to approach this problem is to assume that any public wireless network you connect to has hostile elements connected to it. You should ensure that all traffic is encrypted either using SSL for specific sites, or using a VPN to encapsulate all traffic over the local wireless network.

Many potential risks are passive (e.g. sniffing attacks) or not easy to detect, so it isn't likely a sensible approach to attempt to assess trustworthyness on a network by network basis.

1

Beside tcpdump is there any way for a standard user and for a network aware one to evaluate how dirty water is any free wireless network?

There is no way to find out how insecure a free wireless network really is. You might check with tcpdump what kind of traffic there is currently in the network but this might change any minute. An attacker might just wait for interesting things to happen before the attack gets started or the attacker might just do passive sniffing.

There simply is no way to securely use some untrusted network without making sure that everything is done with HTTPS or a VPN tunnel.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.