Someone sent me this whitepaper on SSID hiding (and why he thinks it's bad).
I've not experienced any of the issues described in the paper. I always considered SSID-hiding to be just a first, minor step to locking down a WLAN, but I'd be interested in what the forum's experiences have been in relation to what this paper states.
I disagree with the paper. SSID hiding is a good initial step to securing your wireless LAN. Sure hidden SSID's can be exposed but it is still more work for an attacker and can keep you more safe from script kiddies with programs like netstumber looking for a wireless lan to attack. WEP can easily be broken but does that mean its a waste of time to configure it? Wireless security is a suite no a sole configuration and must be treated as such. By using any combination of SSID Hiding, WEP, TKIP, Some flavor of EAP, and even VPN, you will end up with a pretty darn secure Wireless LAN. Its the combination that keeps it secure......
There are certainly ways to find out an SSID, but why make it that much easier for a hacker? If you broadcast the SSID in the beacon, it's out there for everyone to see, letting them at minimum, associate to the AP with no effort whatsoever, then they can start working on your authentication and encryption.
Hiding the SSID will make them have to do more work. Unless you are facing something like corporate espionage, where the goal is to crack the network, they're more likely to move on and try to find an easier WLAN to hack into. script kiddies and war-drivers, don't want to work any harder than they have to. As baileja said, hiding your SSID is a good first step to locking down your WLAN, but you need to go all the way and implement encryption, authentication, key management, and other measures to really lock it down.