See other devices connected to public Wifi

Question

Is there a way to see a list of the other devices connected to a public Wifi hotspot, like at Starbucks?

I'm curious if this is possible by non-network administrators.

Solution

Most unencrypted wireless networks have client isolation enabled. This means that users are not aware of each other.

You can test whether or not isolation is enabled by pinging, port scanning, etc., the rest of the subnet.

Comments

[Leonardo Scotti]

Have you tried to use arp - a?

[CodyBugstein]

Yes I was expecting an answer beyond "yes, it's possible". I'm not an unethical individual, just a curious one.

[Bon Gart]

Asking for software recommendations would make your question a Shopping question, which isn't allowed as per the FAQ superuser.com/faq#dontask OR if your question is just a theoretical kind of query then once again, it's not allowed as per the FAQ. There are very few ethical reasons why a non-administrator would want to see what OTHER computers are connected to a public WiFi Hotspot. So few, in fact, that providing a How-To would be akin to teaching others the basics of hacking into other computers connected to a public WiFi. Notice, I have said nothing about your intentions.

[CodyBugstein]

And what's wrong with teaching others the basics of hacking? Your philosophy then would also extend to not wanting to teach kids karate. Honestly I have no malicious intent, I would just like to know what the possibilities are and have an idea of what the guy sitting at the other table might be doing.

[Bon Gart]

I'd say that you just failed miserably to create an analogy. Teaching people karate is not similar to teaching people how to hack into other computer users at a public WiFi hotspot. Teaching Karate may save a life when attacked by a mugger or a drunk. Teaching someone how to hack into other computers at a public WiFi has no positive beneficial aspects. Furthermore, regardless of whether or not you actually have malicious intent, saying that you have no malicious intent was expected. Nervous about the guy next to you? Stop using the public WiFi for anything sensitive.

[Bon Gart]

Moreover, if you want to know how to better protect yourself when using a Public WiFi, then THAT IS THE QUESTION YOU SHOULD BE ASKING as opposed to starting a theoretical discussion on how one might monitor and hack into computers connected to a public WiFi.

[CodyBugstein]

I'm surprised you didn't notice the fallacy of your retort as you typed it. My analogy is sound. Karate lessons teach kids how to fight - nothing good can come of it other than defending against someone who wants to fight with them. The same is true in this context. In order to protect yourself, you have to know what can be done against you.