DSL Filters

[John]

> Q4: What might be special about the phone line connection of a security
> monitoring system?

Actually, the position of the filter is important here.  Many monitoring systems will, when an alarm is tripped, seize the phone line by disconnecting all of the inside wiring to all the phones before dialing the monitoring service company.  If you put a filter on the telco side of the alarm system, you will accomplish the one filter for the entire home goal.

You probably should have the wiring change checked by the alarm monitoring company, too.  Some systems are capable of calling the monitoring company once a day with a status message (all ok, backup battery low, etc.)