The widespread availability of Linksys VoIP adapters makes them a very popular choice with Alarm Dealers worldwide as they can source them in their local area. This avoids expensive shipping and taxation, and keeps the overall cost of the solution to an absolute minimum.
They are available in over 50 countires worldwide and are the ideal device for upgrading legacy alarm panels to IP.
Redundancy Options
For many, it is acceptable to use the popular low cost Linksys PAP2 or similar device to provide an "IP Only" solution that relies 100% on the availability of an Internet connection. It is essential to understand that alarms will not get through to the Monitoring Center if the internet connection is lost or in the event of power failure where all network equipment is not connected to a backup power supply.
For those who are not prepared to rely totally upon their Internet connection, one step up from this is the use of a Linksys SPA3102 VoIP ATA. It has an FXO port that can be connected to a PSTN (POTS) line or to a cellular backup device so that the alarm panel has an alternative transmission path in the event of Internet or power failure. These devices can be provisioned in such a way that when the alarm panel dials the primary number, alarms are sent over the Internet. If that process fails, the panel will dial it's secondary number and the alarm will be sent out of the FXO port and over the PSTN or cellular network.
There is a great article for using an SPA3102 with a BT Line for VoIP in the UK
Concerns about Internet and VoIP Security
Many people are concerned that calls travelling over the Internet are not as secure calls over a PSTN line. This is not the case. If someone wanted to listen in on your landline telephone line all they'd have to do is go into your back yard and connect a device up to your telephone line's copper pair or use an inductive amplified speaker (WAND). For someone to intercept data between your ATA and the Monitoring Centre, they would have to compromise core internet routers or your Monitoring providers server. Then they'd have to come up with some program to monitor the packets and sift out yours from the millions of others and somehow put that data back into the network. Intrusion would have to be intentional and deliberate and it's not for amateurs.
Surely it would be easier for an intruder to just cut the phone line. This has always been a problem for PSTN-only systems and continues to be so where a VoIP service is used as there is no provision for line monitoring. Where the Linksys Alarm Monitoring Solution is used, the importance of line monitoring is fully understood and implemented. ATA's are programmed to send heartbeats every 90 seconds and the server software constantly checks for their arrival. If heartbeats do not arrive at the server within an agreed interval, operators are alerted and can take appropriate action.