The operation centre in Rugby includes a pseudo-network where new devices and software can be tested and approved onto the network. 

“We offer a conformance and certification testing service”, explains Linford Copeland, a system test engineer at Airwave. “If a customer has an upgrade to their system or if we have a software upgrade for our network or hardware, we invite suppliers in and we’ll conformance-test their equipment. We make sure it follows protocols and standards and check it doesn’t have any adverse effects on the rest of the service we provide.”

There are approximately 3800 Airwave base stations in the UK, of which about one-third are high-availability sites. These have dual transmission links to provide resilience in the transmission path. They also have resilience in the power supply. 

Each of these sites has seven days power autonomy so, in the event of a nationwide power failure, the high availability sites keep running for at least seven days. 

These 1200 sites provide relatively thin but total coverage across all the major roads, major cities and airports in the UK. If you took away the other 2600 sites, there is still base level coverage across the country.

The company guarantees a four-hour fix target, which presents some challenges particularly in the highlands and the islands of Scotland. Martin Benke, operations director at Airwave, explains: “One of the differences between us and a mobile operator is the fix targets. Whereas mobile operators have priority sites, in this network, every site, be it the one on the Island of Mull, or the one next to New Scotland Yard, we have to try and fix within four hours.” 

Just over 400 people look after the network. It is a 24-hour a day, 365 day a year operation but they do get some second and third line support from key suppliers – again provided on a round-the-clock basis.

Resilience

In the unlikely event that an Airwave switch is lost, through fire or flood for example, the contract requires that the hot standby switch will take over operation of the network within eight minutes. “The reality is within about 1½ minutes voice services start to appear”, Martin continues. “We have a totally resilient switch network. Every switch has its own mirror that is running there as a hot standby. If the first switch is unavailable, the second switch takes the load. 

“We’ve used it in anger a couple of times, but we actually use it quite a lot because that’s how we upgrade the network. When we want to upgrade the network, we upgrade the standby, cut over to the standby, upgrade the main and cut back to the main. It’s a well-tried, well-rehearsed process. We know we have the most resilient switch network in the world.”

Martin is confident the service Airwave provides is as good as it can be. “When you combine the highly resilient base sites, highly resilient network management, highly resilient switch network, this is a resilient network. I will go so far as to say it has unsurpassed levels of resilience.”