1. A method for cross domain security information conversion, the method comprising: receiving from a system entity, in a security service, security information in a native format of a first security domain regarding a system entity having an identity in at least one security domain; translating the security information to a canonical format for security information; transforming the security information in the canonical format using a predefined mapping from the first security domain to a second security domain; translating the transformed security information in the canonical format to a native format of the second security domain; and returning to the system entity the security information in the native format of the second security domain.