Applications that use Elvin must structure their communicated messages into lists of names and typed-values.

Implementors might choose to publish the notification formats used by their applications to

• preserve a unique namespace, preventing accidental collisions with other applications,
• document their interfaces to promote interoperability with other Elvin applications
• develop common formats for vertical markets or other interest groups served by multiple vendors/applications

Facilities are provided to browse currently registered formats, update an existing format specification, or register a new format.

Inter-process communication in Elvin uses a modular protocol stack, with each module being identified by a short, unique, textual name. The protocol specifications and their allocated names are published via the protocol registry.

The Elvin client protocol supports an extensible security model, in which the format and use of keys is determined by a scheme identifier within the KeyBlock. Scheme definitions and their allocated identifiers are published via the scheme registry.