Diameter Session establishment and disconnection


Diameter Session establishment and disconnection

Diameter session could be initiated from any message that contains Auth-Session-State set to STATE_MAINTAINED or this AVP is absent because it's default value is STATE_MAINTAINED.when server receives this it shall maintain state and does not release resources used in session till session terminates.

All the messages exchanged between a session must have same session-id. A session can initiate another child session usually called sub-session and generally used in Accounting sessions identified by Accounting-Sub-Session-Id AVP. Similarly we can associate multiple session in a scenario, called as Multi-Session. Acct-Multi-Session-Id AVP is used to logically link accounting sessions.



Multi-Session ----------------------------------------------

Session *************************************

Sub-session ================
(I)   
                                       ================
(A) Sub-session ================
(II)
                                       ================

*************************************
(1)

Session *************************************

Sub-session ================
(I)   
                                       ================
(B) Sub-session ================
(II)
                                       ================

*************************************
          -------------------------------------------------


A session shall remain established till one of the following thing
1) Session-Termination-Request is received from client.
2) Abort-Session-Request is issues by server.
3) Session Life time is completed.
4) If either client or server is rebooted, causing change in Origin-State-Id.

Your Comments /Suggestions and Questions are always welcome, shall clarify with best of knowledge. So feel free to put Questions

9 comments:

  1. Hi,
    Is it allowed to have more than one diameter connection under the same Origin-Host? I checked RFC and only found "Origin-Host AVP may resolve to more than one address as the Diameter peer may support more than one address." I think more than one IP address caters for SCTP multi-homing and doesn't fit for TCP.

    ReplyDelete
    Replies
    1. Hi wenming chen,

      Sorry for delayed response, Host-IP-Address AVP is used to share multiple IP addresses those could be used for Multi-Homing feature of SCTP.


      Thanks for your query.
      Happy to help you again.
      Team-Diameter

      Delete
  2. Thanks for your response.
    Does it make any sense in reality that a single diameter endpoint(identified by AVP Origin-Host) to have multiple diameter connections to another endpoint?
    Or shall standard prohibit more than one diameter connections between two diameter endpoints?

    ReplyDelete
    Replies
    1. Hi wenming chen,

      As we know that Multi-Homing is feature of SCTP protocol that runs over Transport Layer, Now in ideal case there would be one Diameter connection with SCTP Multi-Homing feature (i.e. Multiple IP address are published by SCTP ), Rather than multiple diameter connection with peer because DIAMETER runs over Application Layer.

      We hope below link could help you.
      http://diameter-protocol.blogspot.in/2013/08/diameter-connection-establishment.html

      We hope it suffice you, don't shy to revert if not.

      Happy to help you again.
      Team-Diameter

      Delete
    2. Sorry for misleading you to SCTP multi-homing.
      My question is not related to SCTP, but for TCP case. I'm not sure if any Diameter stack implementation shall support more than one Diameter connection which has the same Origin-Host. I tried to search an answer from the RFC but failed. Thus I posted the question here.

      Delete
  3. Does anybody have document supporting that there could be only one SCTP association with a “unique” hostname

    ReplyDelete
  4. Does anybody have some documents to understand that two SCTP links cannot have same HOST name as far as HSS is concerned

    ReplyDelete
  5. Hi team,
    Can CCR-I and CCR-T can come from different Origin-Host with same session-ID over TCP?

    ReplyDelete
  6. Thank you for your information that you've shared.

    Holly

    ReplyDelete