A friendnet is a network topology where every TCP/IP connection is backed up by a meatspace connection. If you are connected to a node which is downloading a lot but refusing uploads, you call the node owner on the telephone. If your pal has a modem and you have DSL, you swap proxying or caching services for help with your car. If you upload a file and your ISP subsequently gets a lawyergram from the RIAA, your friend has lost a friend. If you can't install the software, your friend who has already done it comes over to troubleshoot. A friendnet builds overlay networks on social topology.

Friendnet connections are hard to come by but extremely durable. Hard to come by because not all your friends will be interested in running some dumb software just to swap files with you. Durable because connection lifetime is measured in months rather than minutes. That's not to say that there's a persistent TCP socket open the whole time, rather that you reconnect persistently, day after day. The network grows slowly and decays slowly.

Unlike automated reputation systems like Advogato, the Slashdot moderation system, eBay seller ratings, and MojoNation, reputation management in a friendnet is a manual operation. This is a good thing: humans are good at fuzzy reasoning and computers aren't. The only reputation tools that friendnet implementations need to provide are accounting data: "you still haven't responded to a request"; "Jennifer was extremely generous with bytes last week"; "perhaps you should mention to your friend that the file she gave you is truncated", etc. Reputation is the engine of a friendnet.

Unlike open networks like Gnutella, a friendnet is private. Every breach of privacy is traceable to a real person and will damage a real relationship. The difficulty of achieving a single breach of privacy applies to every transitive link in the chain between an attacker and a target. Unlike anonymous networks like Freenet, a friendnet is not confidential, so a friendnet is a lousy place for porn. Friendnets are private but not confidential.


-- Lucas Gonze, Dec 14, 2002.