Cisco Cisco TelePresence Video Communication Server Expressway 관리 매뉴얼
Applications
Cisco VCS Administrator Guide (X7.0)
Page 243 of 488
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Presentity Manager: an interface to the Presence Database. It is used to support VCS features such
as FindMe and the PUA, where the presence information provided by a number of different devices
must be aggregated in order to provide an overall presence status for one particular presentity. When
the Presentity Manager receives a request from the subscription manager for information on a
presentity, it queries the Presence Database for all information available on all the endpoints
associated with that particular presentity. The Presentity Manager then aggregates this information to
determine the presentity’s current status, and returns this to the Subscription Manager.
as FindMe and the PUA, where the presence information provided by a number of different devices
must be aggregated in order to provide an overall presence status for one particular presentity. When
the Presentity Manager receives a request from the subscription manager for information on a
presentity, it queries the Presence Database for all information available on all the endpoints
associated with that particular presentity. The Presentity Manager then aggregates this information to
determine the presentity’s current status, and returns this to the Subscription Manager.
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Presence Database: stores current presence information received in the form of PUBLISH messages.
Also sends NOTIFY messages to the Presentity Manager to inform it of any changes.
Also sends NOTIFY messages to the Presentity Manager to inform it of any changes.
Presence User Agent (PUA)
Endpoints that do not support presence can have status published on their behalf by the VCS. The
service that publishes this information is called the Presence User Agent (PUA).
service that publishes this information is called the Presence User Agent (PUA).
The PUA takes information from the local registration database and the call manager and determines, for
each endpoint that is currently locally registered, whether or not it is currently in a call. The PUA then
provides this status information via a PUBLISH message.
each endpoint that is currently locally registered, whether or not it is currently in a call. The PUA then
provides this status information via a PUBLISH message.
For the PUA to successfully provide presence information about a locally registered endpoint:
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The endpoint must be registered with an alias in the form of a URI.
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The domain part of the URI must be able to be routed to a SIP registrar that has a presence server
enabled. (This could be either the local Presence Server, if enabled, or another Presence Server on a
remote system.)
enabled. (This could be either the local Presence Server, if enabled, or another Presence Server on a
remote system.)
When enabled, the PUA generates presence information for all endpoints registered to the VCS,
including those which already support presence. The status information provided by the PUA is either:
including those which already support presence. The status information provided by the PUA is either:
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online (registered but not in a call)
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in call (registered and currently in a call)
Aggregation of presence information
When enabled, the PUA generates presence information for all endpoints registered to the VCS,
including those which already support presence. However, endpoints that support presence may provide
other, more detailed status, for example away or do not disturb. For this reason, information provided by
the PUA is used by the Presentity Manager as follows:
including those which already support presence. However, endpoints that support presence may provide
other, more detailed status, for example away or do not disturb. For this reason, information provided by
the PUA is used by the Presentity Manager as follows:
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Where presence information is provided by the PUA and one other source, the non-PUA presence
information will always be used in preference to the PUA presence information. This is because it is
assumed that the other source of information is the presentity itself, and this information is more
accurate.
information will always be used in preference to the PUA presence information. This is because it is
assumed that the other source of information is the presentity itself, and this information is more
accurate.
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Where presence information is provided by the PUA and two or more other sources, the Presence
Server will aggregate the presence information from all presentities to give the "highest interest"
information, e.g. online rather than offline, and in call rather than away.
Server will aggregate the presence information from all presentities to give the "highest interest"
information, e.g. online rather than offline, and in call rather than away.
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If no information is being published about an endpoint, either by the endpoint itself or by the PUA, the
endpoint’s status will be offline. If the PUA is enabled, the offline status indicates that the endpoint is
not currently registered.
endpoint’s status will be offline. If the PUA is enabled, the offline status indicates that the endpoint is
not currently registered.