Cisco TelePresence Administrator's Manual page 86

Ensure all your endpoints, both H.323 and SIP, register with an alias in the form name@domain.
n
Create a pre-search transform on the VCS that strips the @domain portion of the alias for those URIs that
n
are in the form of number@domain.
See the pre-search transforms
the stripping @domain for dialing to H.323 numbers
Cisco VCS Administrator Guide (X7.1)
section for information about how to configure pre-search transforms, and
section for an example of how to do this.
Protocols
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