Simple Authentication and Security Layer
Simple Authentication and Security Layer is a framework for authentication and data security in Internet protocols. It decouples authentication mechanisms from application protocols, in theory allowing any authentication mechanism supported by SASL to be used in any application protocol that uses SASL. Authentication mechanisms can also support proxy authorization, a facility allowing one user to assume the identity of another. They can also provide a data security layer offering data integrity and data confidentiality services. DIGEST-MD5 provides an example of mechanisms which can provide a data-security layer. Application protocols that support SASL typically also support Transport Layer Security to complement the services offered by SASL.
John Gardiner Myers wrote the original SASL specification in 1997. In 2006, that document was replaced by RFC 4422 authored by Alexey Melnikov and Kurt D. Zeilenga. SASL, as defined by RFC 4422 is an IETF Standard Track protocol and is,, a Proposed Standard.
SASL mechanisms
A SASL mechanism implements a series of challenges and responses. Defined SASL mechanisms include:SASL-aware application protocols
Application protocols define their representation of SASL exchanges with a profile. A protocol has a service name such as "ldap" in a registry shared with GSSAPI and Kerberos.protocols currently supporting SASL include:
- Application Configuration Access Protocol
- Advanced Message Queuing Protocol
- Blocks Extensible Exchange Protocol
- Internet Message Access Protocol
- Internet Message Support Protocol
- Internet Relay Chat
- Lightweight Directory Access Protocol
- libvirt
- ManageSieve
- memcached
- Post Office Protocol
- Remote framebuffer protocol used by VNC
- Simple Mail Transfer Protocol
- Subversion protocol
- Extensible Messaging and Presence Protocol