Data uploaded to Swarm is either unnamed or named:

• Unnamed objects are assigned identifiers by Swarm. They are created, updated, accessed, and deleted using an unambiguous UUID. Swarm is optimized to handle unnamed objects most efficiently, and the random assignment of UUIDs to content offers a higher level of programming security.

• Named objects are assigned identifiers by the user. They are created, updated, accessed, and deleted using the chosen name. Multiple objects can be created with the same name as long as they are in different buckets. Because these objects require a name lookup, they cannot perform as well as unnamed objects. Named objects are compatible with the AWS S3 protocol and Swarm clients interfacing with end users through a file system.

Swarm supports three types of data objects: Named, Alias, and Immutable. Two of the three can be updated (are mutable) and two of the three are identified by UUID (are unnamed).

Named Objects

• Named objects must exist in buckets, which must exist in domains. A name only needs to be unique within a bucket. Named objects can be updated, and are always accessed by name and bucket. Another object can be created with the same name, in the same bucket if a named object is deleted.

Alias (mutable) Unnamed Objects

• Alias objects have permanent UUIDs but replaceable content. The UUID cannot be reused: all unnamed objects have the associated UUID retired after being deleted.

Immutable Unnamed Objects

• Immutable objects have UUIDs and content that do not change. Swarm retires the UUID of an immutable object when it is deleted. Using a special header, immutable objects can be locked to prevent deletion, allowing implementation of http://en.wikipedia.org/wiki/Write_Once_Read_Many (See https://perifery.atlassian.net/wiki/spaces/public/pages/2443821972).

To manage objects with Swarm, applications communicate using the Simple Content Storage Protocol (SCSP) or else through the S3 Protocol (named objects only), via Gateway. SCSP methods and syntax are a subset of the HTTP/1.1 standard, with some extensions (see SCSP Essentials). The same SCSP methods apply to all types of objects.

See .