Registration-Termination-Request (RTR) Command
The Registration-Termination-Request (RTR) command is indicated by
the Command-Code set to 287 and the Command Flags' 'R' bit set. The
Diameter server sends this command to the Diameter client in a SIP
server to indicate to the SIP server that one or more SIP AORs have
to be deregistered. The command allows an operator to
administratively cancel the registration of a user from a centralized
Diameter server.
The Diameter server has the capability to initiate the deregistration
of a user and inform the SIP server by means of the Diameter RTR
command. The Diameter server can decide whether only one SIP AOR is
going to be deregistered, a list of SIP AORs, or all the SIP AORs
allocated to the user.
The absence of a SIP-AOR AVP in the Diameter RTR message indicates
that all the SIP AORs allocated to the user identified by the
User-Name AVP are being deregistered.
The Diameter server MUST include a SIP-Deregistration-Reason AVP
value to indicate the reason for the deregistration.
The Message Format of the RTR command is as follows:
<RTR> ::= < Diameter Header: 287, REQ, PXY >
< Session-Id >
{ Auth-Application-Id }
{ Auth-Session-State }
{ Origin-Host }
{ Origin-Realm }
{ Destination-Host }
{ SIP-Deregistration-Reason }
[ Destination-Realm ]
[ User-Name ]
* [ SIP-AOR ]
* [ Proxy-Info ]
* [ Route-Record ]
* [ AVP ]
8.10. Registration-Termination-Answer (RTA) Command
The Registration-Termination-Answer (RTA) is indicated by the
Command-Code set to 287 and the Command Flags' 'R' bit cleared. The
Diameter client sends this command in response to a previously
received Diameter Registration-Termination-Request (RTR) command.
In addition to the values already defined in RFC 3588 [RFC3588], the
Result-Code AVP may contain one of the values defined in
Section 10.1.
If the SIP server (Diameter client) requires a User-Name AVP value to
process the Diameter RTR request, but the Diameter RTR message did
not contain a User-Name AVP value, the Diameter client MUST set the
Result-Code AVP value to DIAMETER_USER_NAME_REQUIRED (see Section
10.1.2) and return it in a Diameter RTA message.
The SIP server (Diameter client) applies the administrative
deregistration to each of the URIs included in each of the SIP-AOR
AVP values, or, if there is no SIP-AOR AVP present in the Diameter
RTR request, to all the URIs allocated to the User-Name AVP value.
The value of the SIP-Deregistration-Reason AVP in the Diameter RTR
command has an effect on the actions performed at the SIP server
(Diameter client):
o If the value is set to PERMANENT_TERMINATION, then the user has
terminated his/her registration to the realm. If informing the
interested parties (e.g., subscribers to the "reg" event
[RFC3680]) about the administrative deregistration is supported
through SIP procedures, the SIP server (Diameter client) will do
so. The Diameter Client in the SIP Server SHOULD NOT request a
new user registration. The SIP server clears the registration
state of the deregistered AORs.
o If the value is set to NEW_SIP_SERVER_ASSIGNED, the Diameter
server informs the SIP server (Diameter client) that a new SIP
server has been allocated to the user, due to some reason. The
SIP server, if supported through SIP procedures, will inform the
interested parties (e.g., subscribers to the "reg" event
[RFC3680]) about the administrative deregistration at this SIP
server. The Diameter client in the SIP server SHOULD NOT request
a new user registration. The SIP server clears the registration
state of the deregistered SIP AORs.
o If the value is set to SIP_SERVER_CHANGE, the Diameter server
informs the SIP server (Diameter client) that a new SIP server has
to be allocated to the user, e.g., due to user's capabilities
requiring a new SIP server, or not enough resources in the current
SIP server. If informing the interested parties about the
administrative deregistration is supported through SIP procedures
(e.g., subscriptions to the "reg" event [RFC3680]), the SIP server
will do so. The Diameter client in the SIP Server SHOULD NOT
request a new user registration. The SIP server clears the
registration state of the deregistered SIP AORs.
o If the value is set to REMOVE_SIP_SERVER, the Diameter server
informs the SIP server (Diameter client) that the SIP server will
no longer be bound in the Diameter server with that user. The SIP
server can delete all data related to the user.
The Message Format of the RTA command is as follows:
<RTA> ::= < Diameter Header: 287, PXY >
< Session-Id >
{ Auth-Application-Id }
{ Result-Code }
{ Auth-Session-State }
{ Origin-Host }
{ Origin-Realm }
[ Authorization-Lifetime ]
[ Auth-Grace-Period ]
[ Redirect-Host ]
[ Redirect-Host-Usage ]
[ Redirect-Max-Cache-Time ]
* [ Proxy-Info ]
* [ Route-Record ]
* [ AVP ]
