Few things come to mind here.
I've done this exact app before.
I keep my devices in a table. The Rails app just displays the
from the table. A background daemon does the actual monitoring.
I get alot more details in my version, including mapping what mac/ip
address are on
which switch port, and using SNMP to the switch to do discovery of
The moral of this is break you ping into a separate process/task. Then
poll yours AP's
and update there status with ActiveRecord.
If you need some help, I can certainly give you some pointers.
glennswest at yahoo dot com dot sg