Overview

Extension state is the state of an Asterisk extension, as opposed to the direct state of a device or a user. It is the aggregate of Device state from devices mapped to the extension through a hint directive. See the States and Presence section for a diagram showing the relationship of all the various states.

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SIP Subscription to Asterisk hints

Under Construction!

Once a hint is configured, Asterisk's SIP drivers can be configured to allow SIP User Agents to subscribe to the hints. A subscription will result in state change notifications being sent to the subscriber.

Configuration for chan_sip is discussed in Configuring chan_sip for Presence Subscriptions

Configuration for res_pjsip is discussed in Configuring res_pjsip for Presence Subscriptions