Sip registration forwarding - Revision history

Anestis Mavrofillidis: /* Configuration */

2024-01-24T13:59:57Z

Configuration

← Older revision		Revision as of 09:59, 24 January 2024
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	\|-		\|-
	\| valign="top" \|		\| valign="top" \|
	*[[Toolpack:~~Creating_a_SIP_Domain_SBC_A~~\|~~3.0~~ Creating a SIP Domain]]		*[[Toolpack:Creating_a_SIP_Domain_SBC_B\|Creating a SIP Domain]]
	*[[Configuring SIP Registration for Open NAP\|3.0 Configuring SIP Registration for Open NAP]]		*[[Configuring SIP Registration for Open NAP\|3.0 Configuring SIP Registration for Open NAP]]
	*[[Configuring SIP Registration for regular NAP\|3.0 Configuring SIP Registration for regular NAP]]		*[[Configuring SIP Registration for regular NAP\|3.0 Configuring SIP Registration for regular NAP]]

Luc Morissette at 19:12, 17 May 2021

2021-05-17T19:12:20Z

← Older revision		Revision as of 15:12, 17 May 2021
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	<br/>		<br/>
	== SIP Calls routing per registered user ==		== SIP Calls routing per registered user ==
	*ProSBC/~~FreeSBCkeeps~~ SIP User Agents' contacts information. This information serves on SIP calls routing when a SIP User Agent is trying to reach a registered user. It could be used also to accept calls from registered users only.		*ProSBC/FreeSBC keeps SIP User Agents' contacts information. This information serves on SIP calls routing when a SIP User Agent is trying to reach a registered user. It could be used also to accept calls from registered users only.

	=== Registered users and routing scripts ===		=== Registered users and routing scripts ===

Luc Morissette at 19:11, 17 May 2021

2021-05-17T19:11:45Z

← Older revision		Revision as of 15:11, 17 May 2021
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	*It supports SIP register requests "Rate Adaptation" between SIP User Agents and registrar.		*It supports SIP register requests "Rate Adaptation" between SIP User Agents and registrar.
	*Because refreshing requests are not always sent to the registrar, the "Rate adaptation" feature reduces SIP register requests sent to the registrar. The "Rate Adaptation" feature is also useful to keep firewall ports open.		*Because refreshing requests are not always sent to the registrar, the "Rate adaptation" feature reduces SIP register requests sent to the registrar. The "Rate Adaptation" feature is also useful to keep firewall ports open.
			<br/>
	== Polling registered users ==		== Polling registered users ==
	Since SIP User Agents may be behind firewalls, it may be necessary to force a quick polling of the registered phone to make sure the port forwarding for the SIP calls stay active. <br/>		Since SIP User Agents may be behind firewalls, it may be necessary to force a quick polling of the registered phone to make sure the port forwarding for the SIP calls stay active. <br/>
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	[[Image:Poll_Registered_Users.png\|800px]]		[[Image:Poll_Registered_Users.png\|800px]]
			<br/>
	== SIP Calls routing per registered user ==		== SIP Calls routing per registered user ==
	*ProSBC/FreeSBCkeeps SIP User Agents' contacts information. This information serves on SIP calls routing when a SIP User Agent is trying to reach a registered user. It could be used also to accept calls from registered users only.		*ProSBC/FreeSBCkeeps SIP User Agents' contacts information. This information serves on SIP calls routing when a SIP User Agent is trying to reach a registered user. It could be used also to accept calls from registered users only.

Luc Morissette: Added diagram

2021-05-17T19:10:33Z

Added diagram

← Older revision		Revision as of 15:10, 17 May 2021
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	== Polling registered users ==		== Polling registered users ==
	Since SIP User Agents may be behind firewalls, it may be necessary to force a quick polling of the registered phone to make sure the port forwarding for the SIP calls stay active. <br/>		Since SIP User Agents may be behind firewalls, it may be necessary to force a quick polling of the registered phone to make sure the port forwarding for the SIP calls stay active. <br/>
			[[Image:Poll_Registered_Users_diagram.png\|800px]]

	To do so, you can use the configuration '''Poll Registered Users''' and select the '''Registered Users Polling Interval'''.<br/>		To do so, you can use the configuration '''Poll Registered Users''' and select the '''Registered Users Polling Interval'''.<br/>
	This interval must be lower than the Firewall's timeouts. Since this may be difficult to find, our experience shows that a polling interval of '''30 seconds''' will work in all cases we have seen.<br/>		This interval must be lower than the Firewall's timeouts. Since this may be difficult to find, our experience shows that a polling interval of '''30 seconds''' will work in all cases we have seen.<br/>

			[[Image:Poll_Registered_Users.png\|800px]]

	== SIP Calls routing per registered user ==		== SIP Calls routing per registered user ==

Luc Morissette: Added section "Polling registered users"

2021-05-17T18:51:37Z

Added section "Polling registered users"

← Older revision		Revision as of 14:51, 17 May 2021
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			{{DISPLAYTITLE:SIP Registration Forwarding}}


	== SIP Registration forwarding overview ==		== SIP Registration forwarding overview ==
	ProSBC/FreeSBC registration forwarding feature allows controlling the registration requests flow between SIP User Agents and registrars.		ProSBC/FreeSBC registration forwarding feature allows controlling the registration requests flow between SIP User Agents and registrars.
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	== NAT traversal ==		== NAT traversal ==
	*ProSBC/FreeSBC handles SIP Calls NAT traversal to allow interaction between SIP User Agents from public and private networks.		*ProSBC/FreeSBC handles SIP Calls NAT traversal to allow interaction between SIP User Agents from public and private networks.
	**~~FreeSBC~~ detects the actual IP from which users have registered, so response messages and SIP Invite requests can be forwarded properly, even in case users are unaware that they are behind a NAT		**SBC detects the actual IP from which users have registered, so response messages and SIP Invite requests can be forwarded properly, even in case users are unaware that they are behind a NAT
	*It supports SIP register requests "Rate Adaptation" between SIP User Agents and registrar.		*It supports SIP register requests "Rate Adaptation" between SIP User Agents and registrar.
	*Because refreshing requests are not always sent to the registrar, the "Rate adaptation" feature reduces SIP register requests sent to the registrar. The "Rate Adaptation" feature is also useful to keep firewall ports open.		*Because refreshing requests are not always sent to the registrar, the "Rate adaptation" feature reduces SIP register requests sent to the registrar. The "Rate Adaptation" feature is also useful to keep firewall ports open.

			== Polling registered users ==
			Since SIP User Agents may be behind firewalls, it may be necessary to force a quick polling of the registered phone to make sure the port forwarding for the SIP calls stay active. <br/>
			To do so, you can use the configuration '''Poll Registered Users''' and select the '''Registered Users Polling Interval'''.<br/>
			This interval must be lower than the Firewall's timeouts. Since this may be difficult to find, our experience shows that a polling interval of '''30 seconds''' will work in all cases we have seen.<br/>

	== SIP Calls routing per registered user ==		== SIP Calls routing per registered user ==

Serdar Civici at 09:11, 25 January 2021

2021-01-25T09:11:37Z

William Wong: /* Configuration */

2019-11-21T09:50:48Z

Configuration

← Older revision		Revision as of 05:50, 21 November 2019
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	\| valign="top" \|		\| valign="top" \|
	*[[Toolpack:Creating_a_SIP_Domain_SBC_A\|3.0 Creating a SIP Domain]]		*[[Toolpack:Creating_a_SIP_Domain_SBC_A\|3.0 Creating a SIP Domain]]
			*[[Configuring SIP Registration for Open NAP\|3.0 Configuring SIP Registration for Open NAP]]
			*[[Configuring SIP Registration for regular NAP\|3.0 Configuring SIP Registration for regular NAP]]
	\|}		\|}

	== References ==		== References ==
	[[SIP_Registration\|SIP Registration]]		[[SIP_Registration\|SIP Registration]]

Luc Morissette: Added link to SIP registration

2018-09-21T15:20:09Z

Added link to SIP registration

← Older revision		Revision as of 11:20, 21 September 2018
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	*[[Toolpack:Creating_a_SIP_Domain_SBC_A\|3.0 Creating a SIP Domain]]		*[[Toolpack:Creating_a_SIP_Domain_SBC_A\|3.0 Creating a SIP Domain]]
	\|}		\|}

			== References ==
			[[SIP_Registration\|SIP Registration]]

Abrassard: Updating doc (not referring to Topology Hiding)

2018-07-05T17:59:52Z

Updating doc (not referring to Topology Hiding)

← Older revision		Revision as of 13:59, 5 July 2018
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	*FreeSBC protects the registrar(s) against excessive SIP User Agents register requests using different strategies (i.e. Firewall, Rate Adaptation, SIP Header Manipulation, Etc.).		*FreeSBC protects the registrar(s) against excessive SIP User Agents register requests using different strategies (i.e. Firewall, Rate Adaptation, SIP Header Manipulation, Etc.).

	== ~~Topology hiding (contact~~ remapping) ==		== Contact remapping ==
	FreeSBC will remap ~~SIP headers (from/~~to/contact~~/via/route.~~.~~.) while forwarding messages between users Registrars/PBX to perform "topology hiding":~~		When forwarding a SIP Register message from a user to the registrar, FreeSBC will remap the contact to make itself the contact.
	* Users always send ~~REGISTER requests to~~ FreeSBC, and ~~receive responses~~ from ~~FreeSBC, even if there are multiple Registrars behind~~.		This way, the Registrar will send response messages through FreeSBC, and thus make sure to "hide" private network topology from users (avoid messages being sent directly from registrar to users).
	* Registrars/PBX addresses are hidden to the ~~users by~~ FreeSBC ~~(multiple registrars can be used for redundancy, and/or per domain~~ name)
	* Multiple users with the same name ~~but from different domains are remapped using "aliases" so they still can be distinguished after going through FreeSBC~~		Because the contact's domain is being remapped, FreeSBC will also remap the contact's user name to make sure there is not user name conflict between two domains that would have the same user name.

	[[Image:registration_topology_hiding.png\|700px]]		[[Image:registration_topology_hiding.png\|700px]]

Abrassard: Replacing TSBC with FreeSBC

2018-06-20T18:53:22Z

Replacing TSBC with FreeSBC

← Older revision		Revision as of 09:59, 24 January 2024
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	\|-		\|-
	\| valign="top" \|		\| valign="top" \|
	*[[Toolpack:~~Creating_a_SIP_Domain_SBC_A~~\|~~3.0~~ Creating a SIP Domain]]		*[[Toolpack:Creating_a_SIP_Domain_SBC_B\|Creating a SIP Domain]]
	*[[Configuring SIP Registration for Open NAP\|3.0 Configuring SIP Registration for Open NAP]]		*[[Configuring SIP Registration for Open NAP\|3.0 Configuring SIP Registration for Open NAP]]
	*[[Configuring SIP Registration for regular NAP\|3.0 Configuring SIP Registration for regular NAP]]		*[[Configuring SIP Registration for regular NAP\|3.0 Configuring SIP Registration for regular NAP]]

← Older revision		Revision as of 05:11, 25 January 2021
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	== SIP Registration forwarding overview ==		== SIP Registration forwarding overview ==
	FreeSBC registration forwarding feature allows ~~to control~~ the registration requests flow between SIP User Agents and registrars.		ProSBC/FreeSBC registration forwarding feature allows controlling the registration requests flow between SIP User Agents and registrars.
	* It allows adaptation of SIP register messages between SIP User Agents and registrars.		* It allows adaptation of SIP register messages between SIP User Agents and registrars.
	* It allows adaptation of [[SIP_subscribe_notify_publish_forwarding\|SIP Subscribe/Publish/Notify forwarding]] messages between SIP User Agents and registrars.		* It allows adaptation of [[SIP_subscribe_notify_publish_forwarding\|SIP Subscribe/Publish/Notify forwarding]] messages between SIP User Agents and registrars.
	* It keeps information about SIP User Agent contacts to allow routing of SIP calls base on registration information.		* It keeps the information about SIP User Agent contacts to allow routing of SIP calls base on registration information.

	[[Image:registration_forwarding_overview.png\|700px]]		[[Image:registration_forwarding_overview.png\|700px]]

	== Forwarding Modes ==		== Forwarding Modes ==
	*FreeSBC always modifies the contact URI in SIP register requests to remain on the path between SIP User Agents and registrars.		*ProSBC/FreeSBC always modifies the contact URI in SIP register requests to remain on the path between SIP User Agents and registrars.
	*FreeSBC supports two different SIP registration forwarding modes (i.e. "Contact Remapping" or "Contact Passthrough").		*ProSBC/FreeSBC supports two different SIP registration forwarding modes (i.e. "Contact Remapping" or "Contact Passthrough").
	*The "Contact Passthrough" forwarding mode makes contact username portion of the ~~contact~~ URI in SIP register requests to pass through unchanged.		*The "Contact Passthrough" forwarding mode makes the contact username portion of the Contact URI in SIP register requests to pass through unchanged.
	*The "Contact Remapping" forwarding mode modifies contact username portion of the ~~contact~~ URI in SIP register requests and make it unique.		*The "Contact Remapping" forwarding mode modifies the contact username portion of the Contact URI in SIP register requests and make it unique.

	== Registrar Selection Mode (registration redundancy) ==		== Registrar Selection Mode (registration redundancy) ==
	*FreeSBC supports Active/Standby registrar selection mode. Users's registration requests are forwarded to the available registrar with highest priority.		*ProSBC/FreeSBC supports Active/Standby registrar selection mode. Users' registration requests are forwarded to the available registrar with the highest priority.
	[[Image:multiple_registrars.png]]		[[Image:multiple_registrars.png]]

	== Protection ==		== Protection ==
	*FreeSBC protects the registrar(s) against excessive SIP User Agents register requests using different strategies (i.e. Firewall, Rate Adaptation, SIP Header Manipulation, Etc.).		*ProSBC/FreeSBC protects the registrar(s) against excessive SIP User Agents register requests using different strategies (i.e. Firewall, Rate Adaptation, SIP Header Manipulation, Etc.).

	== Contact remapping ==		== Contact remapping ==
	When forwarding a SIP Register message from a user to the registrar, FreeSBC will remap the contact to make itself the contact.		When forwarding a SIP Register message from a user to the registrar, ProSBC/FreeSBC will remap the contact to make itself the contact.
	This way, the Registrar will send response messages through FreeSBC, and thus make sure to "hide" private network topology from users (avoid messages being sent directly from registrar to users).		This way, the Registrar will send response messages through ProSBC/FreeSBC, and thus make sure to "hide" private network topology from users (avoid messages being sent directly from registrar to users).

	Because the contact's domain is being remapped, FreeSBC will also remap the contact's user name to make sure there is not user name conflict between two domains that would have the same user name.		Because the contact's domain is being remapped, ProSBC/FreeSBC will also remap the contact's user name to make sure there is not user name conflict between two domains that would have the same user name.

	[[Image:registration_topology_hiding.png\|700px]]		[[Image:registration_topology_hiding.png\|700px]]

	== NAT traversal ==		== NAT traversal ==
	*FreeSBC handles SIP Calls NAT traversal to allow interaction between SIP User Agents from public and private networks.		*ProSBC/FreeSBC handles SIP Calls NAT traversal to allow interaction between SIP User Agents from public and private networks.
	**FreeSBC detects the actual IP from which users have registered ~~from~~, so response messages and SIP Invite requests can be forwarded properly, even in case users are unaware that they are behind a NAT		**FreeSBC detects the actual IP from which users have registered, so response messages and SIP Invite requests can be forwarded properly, even in case users are unaware that they are behind a NAT
	*It supports SIP register requests "Rate Adaptation" between SIP User Agents and registrar.		*It supports SIP register requests "Rate Adaptation" between SIP User Agents and registrar.
	*Because refreshing requests are not always sent to registrar, "Rate adaptation" feature reduces SIP register requests sent to registrar. The "Rate Adaptation" feature is also useful to keep firewall ports open.		*Because refreshing requests are not always sent to the registrar, the "Rate adaptation" feature reduces SIP register requests sent to the registrar. The "Rate Adaptation" feature is also useful to keep firewall ports open.

	== SIP Calls routing per registered user ==		== SIP Calls routing per registered user ==
	*~~FreeSBC keeps~~ SIP User Agents contacts information. This information serves on SIP calls routing when a SIP User Agent is trying to reach a registered ~~users~~. It could be used also to accept calls from registered users only.		*ProSBC/FreeSBCkeeps SIP User Agents' contacts information. This information serves on SIP calls routing when a SIP User Agent is trying to reach a registered user. It could be used also to accept calls from registered users only.

	=== Registered users and routing scripts ===		=== Registered users and routing scripts ===
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	[[Image:registered_users_call_routing_direct.png\|400px]]		[[Image:registered_users_call_routing_direct.png\|400px]]

	FreeSBC routes can also be organized so calls always go through the Registrar/PBX before being forwarded to the called user.		ProSBC/FreeSBC routes can also be organized so calls always go through the Registrar/PBX before being forwarded to the called user.

	[[Image:registered_users_call_routing_through_pbx.png\|700px]]		[[Image:registered_users_call_routing_through_pbx.png\|700px]]
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	In this example, there are 2 routes:		In this example, there are 2 routes:
	* ROUTE_FROM_OPEN_NAP will match all incoming calls received from NAP_OPEN, and forward them to NAP_PBX		* ROUTE_FROM_OPEN_NAP will match all incoming calls received from NAP_OPEN, and forward them to NAP_PBX
	* ROUTE_FROM_PBX will match all incoming calls received from NAP_PBX, and forward them by registered user (will forward to whatever NAP the target user has registered from)		* ROUTE_FROM_PBX will match all incoming calls received from NAP_PBX, and forward them by the registered user (will forward to whatever NAP the target user has registered from)

	Here, if "alice" calls "bob" from NAP_OPEN, the call will be forwarded to the PBX. Then the PBX may route back the call to the SBC, which will then forward to "bob" on NAP_OPEN. In other words, all calls from NAP_OPEN will go through the PBX.		Here, if "alice" calls "bob" from NAP_OPEN, the call will be forwarded to the PBX. Then the PBX may route back the call to the SBC, which will then forward to "bob" on NAP_OPEN. In other words, all calls from NAP_OPEN will go through the PBX.
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	{\| cellpadding="5" border="1" class="wikitable"		{\| cellpadding="5" border="1" class="wikitable"
	\|-		\|-
	! width="200" style="background: rgb(239, 239, 239) none repeat scroll 0% 0%; -moz-background-clip: border; -moz-background-origin: padding; -moz-background-inline-policy: continuous;" \| FreeSBC		! width="200" style="background: rgb(239, 239, 239) none repeat scroll 0% 0%; -moz-background-clip: border; -moz-background-origin: padding; -moz-background-inline-policy: continuous;" \| ProSBC/FreeSBC
	\|-		\|-
	\| valign="top" \|		\| valign="top" \|

← Older revision		Revision as of 14:53, 20 June 2018
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	== SIP Registration forwarding overview ==		== SIP Registration forwarding overview ==
	~~TSBC~~ registration forwarding feature allows to control the registration requests flow between SIP User Agents and registrars.		FreeSBC registration forwarding feature allows to control the registration requests flow between SIP User Agents and registrars.
	* It allows adaptation of SIP register messages between SIP User Agents and registrars.		* It allows adaptation of SIP register messages between SIP User Agents and registrars.
	* It allows adaptation of [[SIP_subscribe_notify_publish_forwarding\|SIP Subscribe/Publish/Notify forwarding]] messages between SIP User Agents and registrars.		* It allows adaptation of [[SIP_subscribe_notify_publish_forwarding\|SIP Subscribe/Publish/Notify forwarding]] messages between SIP User Agents and registrars.
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	== Forwarding Modes ==		== Forwarding Modes ==
	*~~TSBC~~ always modifies the contact URI in SIP register requests to remain on the path between SIP User Agents and registrars.		*FreeSBC always modifies the contact URI in SIP register requests to remain on the path between SIP User Agents and registrars.
	*~~TSBC~~ supports two different SIP registration forwarding modes (i.e. "Contact Remapping" or "Contact Passthrough").		*FreeSBC supports two different SIP registration forwarding modes (i.e. "Contact Remapping" or "Contact Passthrough").
	*The "Contact Passthrough" forwarding mode makes contact username portion of the contact URI in SIP register requests to pass through unchanged.		*The "Contact Passthrough" forwarding mode makes contact username portion of the contact URI in SIP register requests to pass through unchanged.
	*The "Contact Remapping" forwarding mode modifies contact username portion of the contact URI in SIP register requests and make it unique.		*The "Contact Remapping" forwarding mode modifies contact username portion of the contact URI in SIP register requests and make it unique.

	== Registrar Selection Mode (registration redundancy) ==		== Registrar Selection Mode (registration redundancy) ==
	*~~TSBC~~ supports Active/Standby registrar selection mode. Users's registration requests are forwarded to the available registrar with highest priority.		*FreeSBC supports Active/Standby registrar selection mode. Users's registration requests are forwarded to the available registrar with highest priority.
	[[Image:multiple_registrars.png]]		[[Image:multiple_registrars.png]]

	== Protection ==		== Protection ==
	*~~TSBC~~ protects the registrar(s) against excessive SIP User Agents register requests using different strategies (i.e. Firewall, Rate Adaptation, SIP Header Manipulation, Etc.).		*FreeSBC protects the registrar(s) against excessive SIP User Agents register requests using different strategies (i.e. Firewall, Rate Adaptation, SIP Header Manipulation, Etc.).

	== Topology hiding (contact remapping) ==		== Topology hiding (contact remapping) ==
	~~TSBC~~ will remap SIP headers (from/to/contact/via/route...) while forwarding messages between users Registrars/PBX to perform "topology hiding":		FreeSBC will remap SIP headers (from/to/contact/via/route...) while forwarding messages between users Registrars/PBX to perform "topology hiding":
	* Users always send REGISTER requests to ~~TSBC~~, and receive responses from ~~TSBC~~, even if there are multiple Registrars behind.		* Users always send REGISTER requests to FreeSBC, and receive responses from FreeSBC, even if there are multiple Registrars behind.
	* Registrars/PBX addresses are hidden to the users by ~~TSBC~~ (multiple registrars can be used for redundancy, and/or per domain name)		* Registrars/PBX addresses are hidden to the users by FreeSBC (multiple registrars can be used for redundancy, and/or per domain name)
	* Multiple users with the same name but from different domains are remapped using "aliases" so they still can be distinguished after going through ~~TSBC~~		* Multiple users with the same name but from different domains are remapped using "aliases" so they still can be distinguished after going through FreeSBC

	[[Image:registration_topology_hiding.png\|700px]]		[[Image:registration_topology_hiding.png\|700px]]

	== NAT traversal ==		== NAT traversal ==
	*~~TSBC~~ handles SIP Calls NAT traversal to allow interaction between SIP User Agents from public and private networks.		*FreeSBC handles SIP Calls NAT traversal to allow interaction between SIP User Agents from public and private networks.
	**~~TSBC~~ detects the actual IP from which users have registered from, so response messages and SIP Invite requests can be forwarded properly, even in case users are unaware that they are behind a NAT		**FreeSBC detects the actual IP from which users have registered from, so response messages and SIP Invite requests can be forwarded properly, even in case users are unaware that they are behind a NAT
	*It supports SIP register requests "Rate Adaptation" between SIP User Agents and registrar.		*It supports SIP register requests "Rate Adaptation" between SIP User Agents and registrar.
	*Because refreshing requests are not always sent to registrar, "Rate adaptation" feature reduces SIP register requests sent to registrar. The "Rate Adaptation" feature is also useful to keep firewall ports open.		*Because refreshing requests are not always sent to registrar, "Rate adaptation" feature reduces SIP register requests sent to registrar. The "Rate Adaptation" feature is also useful to keep firewall ports open.

	== SIP Calls routing per registered user ==		== SIP Calls routing per registered user ==
	*~~TSBC~~ keeps SIP User Agents contacts information. This information serves on SIP calls routing when a SIP User Agent is trying to reach a registered users. It could be used also to accept calls from registered users only.		*FreeSBC keeps SIP User Agents contacts information. This information serves on SIP calls routing when a SIP User Agent is trying to reach a registered users. It could be used also to accept calls from registered users only.

	=== Registered users and routing scripts ===		=== Registered users and routing scripts ===
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	[[Image:registered_users_call_routing_direct.png\|400px]]		[[Image:registered_users_call_routing_direct.png\|400px]]

	~~TSBC~~ routes can also be organized so calls always go through the Registrar/PBX before being forwarded to the called user.		FreeSBC routes can also be organized so calls always go through the Registrar/PBX before being forwarded to the called user.

	[[Image:registered_users_call_routing_through_pbx.png\|700px]]		[[Image:registered_users_call_routing_through_pbx.png\|700px]]