Distributed Hash Table (DHT)
- Distributed system providing lookup service similar to hash table
- It can scale to extremely large numbers of nodes to handle continual node arrivals, departures, and failures.
- Originally developed for P2P system like BitTorrent
- It is decentralized in nature
- Examples
- P2P file sharing (torrent)
- Distributed File Systems
- DNS
- CDN
- Anycast, Multicast
DHT Algorithms
- Consistent Hashing
- delta(k1, k2) is defined, where k1, and k2 are keys
- for example clockwise distance on a circle from k1 to k2
- Rendezvous Hashing
- aka Highest random weight (HRW) hashing