Decentralized Contact Tracing Protocols

Chakraborty, Pranab; Maitra, Subhamoy; Nandi, Mridul; Talnikar, Suprita

Digital Contact Tracing (DCT) protocols and systems usually rely upon close-range communication between handheld devices (like smartphones or tablets), primarily using the Bluetooth Low Energy (BLE) interface and a client-server mode of communication between the apps installed on the devices and the backend server(s). Depending upon the role played by the backend server(s), DCT protocols, and systems are usually classified under centralized or decentralized categories. In this chapter, we focus on decentralized DCT protocols, namely, Apple-Google Exposure Notification Framework (ENF), DP3T, East Coast PACT, West Coast PACT, and TCN. Towards the end, we describe Epione, which though categorized under decentralized systems according to the classification provided in Chap. 10.1007/978-981-15-9727-5_2, contains many features akin to that of centralized systems.