However, PEPP-PT is a co-ordination effort which contains both centralised and decentralised approaches, and is not a single protocol.Decentralised protocols include Decentralized Privacy-Preserving Proximity Tracing (DP-PPT/DP-3T), Temporary Contact Numbers (TCN, fka Contact Event Numbers, CEN), Privacy Sensitive Protocols and Mechanisms for Mobile Contact Tracing (PACT) and others.