CASP (Content-addressable Storage Publishing)

CASP allows publishing any feed of records (Activity Streams, RSS, etc.) as a series of
Content Addressable aRchives.
This makes any publishing feed highly available because feeds are no longer bound to a single URL
(or to a provider as an organizational entity) and can be uploaded to and downloaded from multiple hosts.

Each CASP feed is blockchain-like in structure, where the hashes of feed entries are signed by the author's private key(s).

Each feed has a Decentralized Identifier, and the corresponding DID document
contains profile information and public cryptographic keys used to verify the authenticity of CASP feeds.

Main outcomes of the project

• authors are not dependent on ActivityPub server admins and can publish content to several CASP hubs in parallel;
• no more migration issues between ActivityPub hubs — you own your data;
• the highly available CASP architecture mitigates the periodic downtimes of independent hubs and
  makes the whole network rock-solid.

The CASP-powered MultiSync is used as the data-exchange backend for the
local-first knowledge-management application Piki.