Gossip Efficiency: Decentralized Systems

This lecture covers the concept of gossip efficiency in decentralized systems, focusing on the I HAVE /SENDME protocol used in UseNet/NNTP. It discusses how message content is sent only once per node, the need for interaction, and the redundancy of Message-IDs. The instructor also explores the challenges of minimizing bandwidth usage without interaction and presents algorithms like Rumor-mongering. The lecture then delves into the naive gossip approach, where the efficiency is determined by the maximum degree of any node. It concludes with an analysis of the efficiency of different search algorithms, including unstructured and structured search, and optimizations like the Expanding-ring search and Bubble Storm.