Cisco TelePresence Administrator's Manual page 92

registration will not expire at the end of the registration timeout period and must be removed manually.
SIP re-registrations contain the same information as the initial registrations so will be filtered by the
n
restriction policy. This means that, after the list has been activated, all SIP registrations will disappear at
the end of their registration timeout period.
The frequency of re-registrations is determined by the Registration expire delta setting for
configuration > Protocols > SIP >
configuration > Protocols >
Cisco VCS Administrator Guide (X7.1)
Configuration) and the Time to live setting for
H.323).
Registration control
SIP (VCS
H.323 (VCS
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