Erlang efficiency meaning

Erlang efficiency describes, in telecommunications contracts and regulatory work, the average utilisation of a transmission route, expressed as Erlangs per circuit on a given route. One Erlang equals continuous occupancy of a single circuit for one hour. Erlang efficiency is calculated by dividing total traffic (in Erlangs) by the number of circuits in the route or trunk group. In legal practice it is used in interconnection agreements, wholesale capacity contracts and service level agreements to evidence network capacity, define grade of service or blocking thresholds, allocate responsibility for congestion, and support pricing or liquidated damages linked to utilisation. It can be relevant in disputes about service quality and in due diligence on network capability. Regulators (such as Ofcom and ComReg) use Erlang-based traffic modelling in cost and charge controls to assess efficient network design and termination rates. This is an engineering term rather than a defined legal term; there is no statutory or case law definition. Its meaning and usage are broadly consistent across England & Wales, Scotland, Northern Ireland and Ireland.