PCI-DSS section 11.2 requires the business to "Test for the presence of wireless access points and detect unauthorized wireless access points". However, this is more easily said than done. Simply scanning to detect wireless access points (as many suggested here) pulls up over 120 APs, both on adjoining floors of our building and in surrounding buildings - in one case, a department store half a dozen floors down and over a long block away!
The biggest problem with walkarounds is that signal strength is a poor tool for location, and as @AviD pointed out in the other thread, a wireless AP could easily be so small or hidden that detecting it on walkaround is highly unlikely. Are there cheap, readily available antennas to provide good directional cues, a poor man's triangulation?
I know that Wireless IDS solutions like Aruba Networks can deploy sensors to perform triangulation. I have seen very few such solutions actually deployed, and when deployed they require sensitive care and tuning. I'm not eager to see what the false positive rate would look like given the number of APs on floors above and below us. But maybe someone has experience with a product that they felt was worth it?
So, I guess my question is - what are people doing to meet 11.1 that provides some security benefit, as opposed to policy compliance?
(I also find it hard to bite into this problem because it's so pointless. Most cell phones could provide a tethered connection between the corporate network and the outside world and be invisible to wireless scanning. And if it was scanned, it would look just like all the worker bees using their phones, and it can't be jammed legally. But that's not in PCI-DSS, so don't worry about it!)