SIP subscribe notify publish forwarding
(Changing TSBC to FreeSBC) |
|||
Line 1: | Line 1: | ||
− | + | FreeSBC can forward SIP Subscribe, Notify and Publish messages between users and registrars (PBX).<br/> | |
Forwarding of these messages follow the same rules as forwarding of [[Sip_registration_forwarding|SIP registration]]. | Forwarding of these messages follow the same rules as forwarding of [[Sip_registration_forwarding|SIP registration]]. | ||
Line 12: | Line 12: | ||
== SIP Subscribe/Publish forwarding == | == SIP Subscribe/Publish forwarding == | ||
− | + | FreeSBC will forward SUBSCRIBE or PUBLISH requests from users to Registrar (PBX) | |
[[Image:subscribe_request_overview.png|700px]]<br/> | [[Image:subscribe_request_overview.png|700px]]<br/> | ||
Line 19: | Line 19: | ||
== SIP Notify forwarding == | == SIP Notify forwarding == | ||
− | + | FreeSBC will forward NOTIFY requests from Registrar (PBX) back to users. | |
[[Image:notify_request_overview.png|700px]]<br/> | [[Image:notify_request_overview.png|700px]]<br/> | ||
Line 26: | Line 26: | ||
== Topology hiding (contact remapping) == | == Topology hiding (contact remapping) == | ||
− | + | FreeSBC will remap SIP headers (from/to/contact/via/route...) while forwarding messages between users Registrars/PBX to perform "topology hiding": | |
− | * Users always send SUBSCRIBE requests to | + | * Users always send SUBSCRIBE requests to FreeSBC, and receive NOTIFY from FreeSBC, even if there are multiple Registrars behind. |
− | * Registrars/PBX addresses are hidden from the users by | + | * Registrars/PBX addresses are hidden from 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 | + | * 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:subscribe_topology_hiding.png|700px]] | [[Image:subscribe_topology_hiding.png|700px]] | ||
Line 35: | Line 35: | ||
== SIP authorization == | == SIP authorization == | ||
SIP authorization requests (401/407 Unauthorized) are forwarded from Registrar to users, allowing users to send request again with appropriate credentials.<br/> | SIP authorization requests (401/407 Unauthorized) are forwarded from Registrar to users, allowing users to send request again with appropriate credentials.<br/> | ||
− | + | FreeSBC does not perform authorization by itself, only forwards between users and registrars. | |
== NAT traversal == | == NAT traversal == | ||
− | * | + | *FreeSBC handles SIP Subscribe NAT traversal to allow interaction between SIP User Agents from public and private networks. |
− | ** | + | **FreeSBC detects the actual IP from which users are sending messages, so responses and Notify messages can be forwarded properly, even in case users are unaware that they are behind a NAT |
== Configuring == | == Configuring == |
Revision as of 13:23, 20 June 2018
FreeSBC can forward SIP Subscribe, Notify and Publish messages between users and registrars (PBX).
Forwarding of these messages follow the same rules as forwarding of SIP registration.
Contents |
SIP Subscribe overview
The SIP SUBSCRIBE method allows users to subscribe to various services, and get notified of events related to these services. Typical services (packages) that phones will register to are:
- Voice mail
- Presence
- Conference
Each user's device can register to various packages, then receive notifications for each of these package (independently).
SIP Subscribe/Publish forwarding
FreeSBC will forward SUBSCRIBE or PUBLISH requests from users to Registrar (PBX)
SIP Notify forwarding
FreeSBC will forward NOTIFY requests from Registrar (PBX) back to users.
Topology hiding (contact remapping)
FreeSBC will remap SIP headers (from/to/contact/via/route...) while forwarding messages between users Registrars/PBX to perform "topology hiding":
- Users always send SUBSCRIBE requests to FreeSBC, and receive NOTIFY from FreeSBC, even if there are multiple Registrars behind.
- Registrars/PBX addresses are hidden from 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
SIP authorization
SIP authorization requests (401/407 Unauthorized) are forwarded from Registrar to users, allowing users to send request again with appropriate credentials.
FreeSBC does not perform authorization by itself, only forwards between users and registrars.
NAT traversal
- FreeSBC handles SIP Subscribe NAT traversal to allow interaction between SIP User Agents from public and private networks.
- FreeSBC detects the actual IP from which users are sending messages, so responses and Notify messages can be forwarded properly, even in case users are unaware that they are behind a NAT
Configuring
SIP Subscribe/Publish/Notify forwarding is automatically available when configuring SIP Domain for SIP Registration forwarding: