Harrow School.

Harrow is one of Britain’s leading independent schools, providing a high-quality boarding school education for boys. An educational institution since 1572 with an impressive cast of alumni including seven Prime Ministers; 19 Victoria Cross holders.


Harrow’s communications infrastructure covers their entire campus which is no less than 400-acres. It includes its own farm, fishing lake, 24 tennis courts and of course, squash courts (the game was invented here).

All services on this vast estate are managed and provided by Harrow’s IT department. As a single centralised phone system, it has provided service to every phone on site; from the Headmaster’s boardroom to the Admissions office call centre to landlines in the staff’s private residences and a payphone for the pupils to use. At this scale, it can be safely described as somewhat of a private telephony exchange.

Business Requirements

• Technology that can keep up in an ever-changing digital era

As times move on traditions at Harrow remain unchanged. Boys still “Cap” (salute) the “Beak” (headmaster) as they’re on their way to the “Ducker” (swimming pool). And if they don’t – one might be writing “Doubles” or doing other “Jerks” (method of punishment – run at 5:30 am every Friday). Traditions might remain the same for centuries, however technology has to move on to reflect the modern world.

Arden Group were tasked with aligning the ageing telephony platform to the current state of the art IT infrastructure.


For many years Arden Group have been Harrow’s communication technology partner of choice. A number of design meetings were arranged and after careful consideration, some windows of downtime were planned where this adventurous work could be done. Arden Group’ project team started the design process and worked closely with Harrow’s IT team on a converged upgrade path. Understanding the challenge was important and every eventuality was considered as downtime windows were limited in timescale.


Arden Group’s expertise in both older TDM based voice and the new converged world of virtualised IP gave us the added experience to control this mammoth legacy “private exchange” upgrade to a supported technology moving forward. Further to this we have now just recently migrated all of the core telephony exchanges to an all-IP virtualised core, utilising Harrow’s private cloud resources and now initiate all calls over SIP.

Finally, Arden Group have expanded the central infrastructure to add geographical resilience and protect Harrow from the “worst case scenario”. All of these steps were done with great attention to detail protecting previous investment, organisational interests and respecting strict downtime limitations.