Roaming problem: Network definition 'Subnet' does not exist

[mytoysips]

Hey,

we have a site with MSM760 WLC (OS: 5.4.2.0-01-9355) with 12 APs. WLC, APs and Users are on the same network.

We use radius authentication and I have enabled Fast wireless roaming on the particular VSC.

Every day I receive 4-5 errors like this:
Apr  2 09:55:50 err    eapolserver  Network definition 'Subnet' does not exist (mac-address="some random MAC Address")

I guess that there's some issue with roaming. I did not enable Wireless mobility because I'm working only with one /16 subnet. Am I doing it right? Maybe you have any idea what this error could mean?

Also another question: imagine a typical office building (4 floors). What would be the approx. distance between the 802.11b/g APs to support voice over wi-fi?

Thank you for your help!

[mytoysips]

Any ideas, anyone? :(

[JesseR]

No idea regarding the error msg your getting.  What did HP support say?

As for distance between APs for VoIP, wow, that's impossible to say.  It all depends on the volume of wireless traffic and number of wireless connections, and also on the building design/structure and potential obstacles (drywall, concrete walls, metal shelving/plating, even different types of glass (regular indoor glass versus UV blocking glass), etc.) that can cause interference or reduce your signal coverage areas.  In an open area with little/no obstancles, a single AP can easily cover 150-250 feet and maintain a decent signal.  That same AP, may only have adequate coverage for 25-30 feet of interior space depending on if it's in a confined room with concrete walls surrounding it, obstacles, etc.   Coverage also changes for 5Ghz vs 2.4Ghz.  2.4Ghz spectrum permeates barriers better than 5Ghz.   So unfortuantely, it's impossible to answer your question without seeing the environment first hand or at least knowing a LOT more about it.

JR