The Provision of Fixed Line Telephony and Numbers

Number 10 Information Communication Technology Services (ICTS) provide ICT services to the Prime Minister and staff of 10 Downing Street. The Fixed Line Telephony (FLT) service is an essential component of these services, providing the functionality to communicate across the various teams and departments within No.10, throughout government, and beyond. With the cessation of ISDN services in 2025, the Buyer requires the delivery of a replacement Session Internet Protocol (SIP) service to provide the lines and numbers. The service requirements have to reflect that FLT must be available 24/7, including Bank Holidays and Christmas. Resilience and security are essential to the service.