In late 2005 We we approached to replace an aging Panasonic system for a British Public School.
The driving force for moving to voip was that the site was spread over a wide area and different buildings and to provide telephones to the remote buildings would prove too expensive.
The system was replaced with a central Asterisk server with nearly 80 extensions. The core LAN was upgraded to Netgear Layer 3 switches with Powerdsine POE midspans.
The remote buildings added extra complexity as one was on the other side of a public road.
To overcome this, this building was connected to the main site via a “Point to Point” Wifi link. The other building was closer and could be connected via a Fibre Link between the it and the main building.
The system was configured to use account codes in public areas, These handsets can only make emergency or internal calls unless a validated account code is entered.
The handsets used were a mix of Aastra 480i and 9133i because of build quality, reliability and BLF support.
The system has now been in place for over 2 and a half years now and in that time the only faults have been either ISDN failing or cable faults. This is a great demonstration of the reliabilty of Asterisk and Aastra handsets and voip in general.
UPDATE
We have since writing this post updated the system on new hardware as part of a refresh. They are now running on a newer version of Asterisk and have more buildings connected to the network.