Cisco TelePresence Video Communication Server Administrator's Manual page 185

These services can be enabled and disabled separately from each other, depending on the nature of
your deployment. Both are disabled by default.
Note that SIP mode must be enabled for the Presence services to function.
Presence User Agent (PUA)
The PUA provides presence information on behalf of registered endpoints.
Field Description
SIP Enabled: if the PUA is enabled, it will publish presence information for all locally
SIMPLE registered endpoints, whether or not those endpoints are also publishing their own
Presence presence information. Information published by the PUA will be routed to a Presence
User Server acting for the endpoint's domain. This could be the local Presence Server, or (if
Agent this is disabled) a Presence Server on another system that is authoritative for that
domain.
Disabled: if the PUA is disabled, only those endpoints that support presence will publish
presence information. No information will be available for endpoints that do not support
presence.
Presence Server
The Presence Server manages the presence information for all presentities in the SIP domains for
which the VCS is authoritative.
Field Description
SIP Enabled: if the local Presence Server is enabled, it will process any PUBLISH
SIMPLE messages intended for the SIP domains for which the local VCS is
Presence authoritative. All other PUBLISH messages will be proxied on in accordance
Server with the VCS's SIP routing rules. Note that SIP routes are configured using the
CLI only.
Disabled: if the local Presence Server is disabled, the VCS will proxy on all
PUBLISH messages to one or more of its neighbor zones in accordance with its
locally configured
whether or not it is authoritative for the presentity's domain. If one of these
neighbors is authoritative for the domain, and has a Presence Server enabled,
then that neighbor will provide presence information for the presentity.
Regardless of whether or not the Presence Server is enabled, the VCS will still continue to receive
PUBLISH messages if they are sent to it from any of the following sources:
locally registered endpoints that support presence
n
the local PUA (if enabled)
n
remote SIP Proxies
n
Recommendations
VCS Expressway and VCS Control: the recommended configuration for a VCS Expressway
n
when acting as a traversal server for a VCS Control is to enable the PUA and disable the Presence
Server on the VCS Expressway, and enable the Presence Server on the VCS Control. This will
ensure that all PUBLISH messages generated by the PUA are routed to the VCS Control.
Cisco VCS Administrator Guide (X6.1)
call routing rules. The local VCS will do this regardless of
Applications
Usage
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