Peer-to-Peer
An architecture where participants communicate directly rather than through a central server.
Peer-to-peer architecture has participants exchange data with each other directly rather than through a server. The appeal is structural: no server to run, no server to pay for, no server to be a bottleneck or a single point of failure, and no operator holding everyone's data.
The costs are equally structural. Participants must find each other, which usually requires some central component even in an otherwise decentralized design. Connectivity is unreliable — most participants sit behind network address translation and cannot accept incoming connections without traversal techniques. State lives on peers, so it disappears when they do, unless something replicates it; see Conflict-Free Replicated Data Type. And nothing is authoritative, which means rule enforcement is advisory: a determined participant can modify their own client.
That last point is a design decision rather than a defect. For a game among friends, client-side enforcement is a reasonable trade — the alternative is infrastructure nobody wants to run, and the threat model does not justify it. For anything competitive or valuable, it is not.
The pattern is at its best where the value is in the connection rather than in stored state, and where "no server I run" is a goal in itself rather than merely a cost saving.
See also8
Signaling Server
The small coordination service peers use to find each other before connecting directly.
Networks & Distribution10 connections
Battle Royale
A many-player elimination format that uses a shrinking play area to force an ending the players would otherwise avoid.
Play & Games11 connections
WebRTC
The browser standard for direct peer connections carrying audio, video, and arbitrary data.
Networks & Distribution14 connections
Eventual Consistency
A guarantee that replicas converge given no further updates, without guaranteeing when.
Networks & Distribution22 connections
Idempotence
The property that performing an operation twice has the same effect as performing it once.
Systems & Tooling34 connections
Virtual Private Network
An encrypted tunnel that presents a remote network as local, and the narrow set of things a commercial one actually hides.
Networks & Distribution22 connections
Network Effect
A good whose value to each user grows as more people use it.
Meaning & Society20 connections
BitTorrent
A peer-to-peer file-sharing protocol from 2001 in which everyone downloading a file also uploads pieces of it to others, so popular files get faster as more people want them, and its legitimate and pirate uses.
Networks & Distribution5 connections
Linked from12
- Battle RoyalePlay & Games
A many-player elimination format that uses a shrinking play area to force an ending the players would otherwise avoid.
- BitTorrentNetworks & Distribution
A peer-to-peer file-sharing protocol from 2001 in which everyone downloading a file also uploads pieces of it to others, so popular files get faster as more people want them, and its legitimate and pirate uses.
- Conflict-Free Replicated Data TypeNetworks & Distribution
A data structure whose replicas can be edited independently and always converge without coordination.
- Eventual ConsistencyNetworks & Distribution
A guarantee that replicas converge given no further updates, without guaranteeing when.
- IPv6Networks & Distribution
IPv6 exists mainly to end address scarcity, with a large enough space that per-device NAT becomes optional.
- NAT TraversalNetworks & Distribution
NAT traversal is the set of tricks two devices behind separate routers use to open a direct connection anyway.
- Network Address TranslationNetworks & Distribution
Rewriting the addresses in packets as they cross a router so that many devices can share one public IPv4 address, a stopgap that became permanent and broke the internet's end-to-end design.
- Network EffectMeaning & Society
A good whose value to each user grows as more people use it.
- Rollback NetcodePlay & Games
A networking model that hides latency by predicting inputs and silently resimulating when the prediction was wrong, instead of freezing to wait.
- Signaling ServerNetworks & Distribution
The small coordination service peers use to find each other before connecting directly.
- Virtual Private NetworkNetworks & Distribution
An encrypted tunnel that presents a remote network as local, and the narrow set of things a commercial one actually hides.
- WebRTCNetworks & Distribution
The browser standard for direct peer connections carrying audio, video, and arbitrary data.