Re: IP changeover Procedures
Akhil Jain <[email protected]> Fri, 11 Dec 2009 20:24:23 +0530 (IST)
| Newsgroups | gmane.ietf.megaco |
|---|---|
| Message-ID | <[email protected]> |
Hi Schwarz, Here are the answers and some more info: -- MGC will use a MID ([email protected]) in FQDN format (which get resolves in IP1 and IP2). 1. MG has entries for both the IP's i.e. IP1 and IP2 corresponding to MGC. 2. Now as soon as MG sends a ServiceChange Request to MGC (consider IP1) MGC replies through IP1 and association has been created. In this reply MGC has used [email protected] as MID. Following is the reply: MEGACO/1 <[email protected]>:2944 Reply=11{Context=-{ServiceChange=ROOT{Services{VERSION=2,ServiceChangeAddr=[IP1]:2944,20091211T13451100}}}} 3. Now after some time IP1 goes down at MGC end. 4. Now MGC sends a ServiceChange message from IP2,mentioned below: MEGACO/2 <[email protected]>:2944 Transaction=9{Context=-{ServiceChange=ROOT{Services{Method=HandOff,Reason="903 MGC Directed Change",MgcIdToTry=[IP2]:2944,20091211T13452000}}}}| In Handoff request MID has not been changed because Its the same MGC, only the active interface has changed to IP2.So Now, shall MG will reply to this service change and then again initiate Handoff procedure with IP2 ? The only difference with § 8.2/H.Sup7 is we have same MGC involved in Handoff Procedure and IP1,IP2 reside on same MGC and get resolved from same MID ([email protected]). ThanksAkhil Jain --- On Fri, 11/12/09, Schwarz Albrecht <[email protected]> wrote: From: Schwarz Albrecht <[email protected]> Subject: RE: [Megaco] IP changeover Procedures To: "Akhil Jain" <[email protected]>, [email protected] Date: Friday, 11 December, 2009, 3:03 PM Your description is still not complete, see below. See also § 8.2/H.Sup7. From: Akhil Jain [mailto:[email protected]] Sent: Donnerstag, 10. Dezember 2009 08:46 To: [email protected]; Schwarz Albrecht Subject: RE: [Megaco] IP changeover Procedures Hi Schwarz, Sorry for delay in responding. Here is the detailed info: 1. MGC makes an association with peer gateway.It fills MID as [email protected] and fills ServiceChangeAddress as IP1. [[Schwarz, Albrecht]] Did the MG accept the request? I.e., is there an established CA? 2. Now IP1 goes down at MGC end. 3. MGC is now sending a ServiceChange Message (Method Handoff) from IP2 with MID as [email protected] and fills MGCIDtotry field with IP2. [[Schwarz, Albrecht]] The H.248 Message for the MGC_1-initiated Handoff request is identified by "MID as xxx@yyy", but which MID value carries the ServiceChangeMgcID? Really ServiceChangeMgcID = 'IP2'? So shall MG be able to handle the request and will it reply to IP2 ? [[Schwarz, Albrecht]] only if the indicated secondary MGC is listed in the MG database of MGC instances, see Table 2/H.Sup7 Thanks Akhil Jain --- On Tue, 1/12/09, Schwarz Albrecht <[email protected]> wrote: From: Schwarz Albrecht <[email protected]> Subject: RE: [Megaco] IP changeover Procedures To: "Akhil Jain" <[email protected]>, [email protected] Date: Tuesday, 1 December, 2009, 11:29 AM Akhil, it's difficult to answer your questions because there's some information missing. The constitution of a CA (Control Association) is tightly coupled to the MID (see § 5.2/H.Sup7). The MID values are missing on your scenarios. Please provide that info, too. Concerning the ServiceChangeMgcID scenario, could you please refer to § 8/H.Sup7 (§ 8.2) and indicate the difference? Concerning the ServiceChangeAddress scenario, H.Sup7 is fairly clear that this parameter may be used for IP interface redirections, during CA establishment phases (i.e., the CA is NOT yet existent). Again pls refer to H.Sup7? From: [email protected] [mailto:[email protected]] On Behalf Of Akhil Jain Sent: Donnerstag, 26. November 2009 06:09 To: [email protected]; Kevin Boyle Subject: Re: [Megaco] IP changeover Procedures Hi, Can someone please help ? --Akhil Jain --- On Sat, 21/11/09, Akhil Jain <[email protected]> wrote: From: Akhil Jain <[email protected]> Subject: RE: [Megaco] IP changeover Procedures To: [email protected], "Kevin Boyle" <[email protected]> Date: Saturday, 21 November, 2009, 9:33 PM Hi Kevin, Thanks for the reply. So if MGC-active sends a Service change from IP2 (as IP1 has been down) then shall it will fill Handoff as reason and new IP address as IP2 in MGCIDtotry field ? If that is the case then shall MG will reply on the new IP i.e. IP2 ? Kindly help. Thanks Akhil Jain --- On Wed, 18/11/09, Kevin Boyle <[email protected]> wrote: From: Kevin Boyle <[email protected]> Subject: RE: [Megaco] IP changeover Procedures To: "'Akhil Jain'" <[email protected]>, [email protected] Date: Wednesday, 18 November, 2009, 8:49 PM Hi Akhil, A change of address for the MGC implies a new control association. That does not necessarily mean that any contexts will be altered; all it means is that the control association has undergone a change. It is up to the MGC to clean up anything on the MG that is out-of-whack. Given that this is really the same MGC (though the MG cannot possibly know that), the MGC can choose to take NO action and continue everything as it is. I will note that the change of interface will take a non-zero amount of time, so there is the possibility that messages will be lost. The spec is pretty clear that the MG has to send replies back to where the command came from, so there is no way that a change of IP address can not result in a change of association (see H.248.1, Clause 9). There is no way the MG could know that the MGC is the same one after the change of interfaces. Please see H.248.1 Annex F for normative details on the ServiceChange procedures that are then used in the overall procedures in Supplement 7. Kevin From: [email protected] [mailto:[email protected]] On Behalf Of Akhil Jain Sent: Wednesday, November 18, 2009 5:30 AM To: [email protected] Subject: [Megaco] IP changeover Procedures Hi All, Per our Implementation, we need to provide Interface Redundancy at MGC end, the architecture we were going to implement is MGC-Active will have 2 IP interfaces and MGC-Standby will have 2 IP interfaces.Can someone help in answering following things: 1. If an Association has been established between MGC-Active (IP1) and peer MG, and now IP1 of MGC-Active has gone down and IP-2 of MGC-Active needs to takeover without breaking the current control association how can we achieve that? <<< Per "Updated Draft ITU-T H.Sup7 “Gateway Control Protocol: Establishment Procedures for the H.248 MGC-MG Control Association” (Ed. 0.14)" ServiceChangeAddress field can be used by MGC to tell new IP address for remaining association. But the document has suggested the use of Service Change Address field in the "Association Establishment Phase". Another thing if MGC sends ServiceChangeMethod as "Handoff" then It would mean that MGC wants a new association but that is not the case, MGC only wants to change the address for rest of the association. >>> 2. If we use MGCIDtotry field in the ServiceChange command then MGC will send this command through IP2 (as IP1 of MGC has been down) so, how will MG got to know that this request has been sent by MGC that has been registered on IP1. Shall it recognizes the MGC via MID ? Kindly help! Thanks Akhil Jain Now, send attachments up to 25MB with Yahoo! India Mail. Learn how. The INTERNET now has a personality. YOURS! See your Yahoo! Homepage. The INTERNET now has a personality. YOURS! See your Yahoo! Homepage. The INTERNET now has a personality. YOURS! See your Yahoo! Homepage. The INTERNET now has a personality. YOURS! See your Yahoo! Homepage. http://in.yahoo.com/ _______________________________________________ Megaco mailing list [email protected] https://www.ietf.org/mailman/listinfo/megaco