(Ez Publish >= 5.0)
At the time of the 5.0 release, two authentication methods were supported: session, and basic. Session based authentication is meant to be used for AJAX operations. It will let you re-use the visitor's session to execute operations with their permissions. Basic authentication will be useful when writing cross-server procedures, when one server executes operations on one/several eZ Publish instances (remote publishing, maintenance, etc).
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