On 03/22/2012 11:45 PM, Vivek Batra wrote: > Hi Folks, > > Just a small bit about the registration behaviour of Registrar server to > take care of errorneous condition; > > 1. UA sends REGISTER message with Call-Id 1 and from IP Address 1 to > Registrar server. Registrar server stores the location (IP1) of UA. > 2. UA application crashes (power down, bug etc) and restarts, so DHCP server > assigns IP2 to UA. UA again sends REGISTER message with Call-Id 2 and from > IP2. Registrar server stores new location (IP2 along with IP1) of UA. > > Now Registrar server has two registration bindings of same physical UA viz > IP1 and IP2. Till the timeout of IP1 (by default 3600 seconds), that binding > (IP1) shall remain live in the registrar server. Any proxy module requesting > registrar sever for the location information of UA gets two binding viz IP1 > and IP2 however IP1 nowhere exists in the network. Any solution to take care > of this?
First, the registrar doesn't store IP1 and IP2, it stores the Contact URIs supplied in the REGISTER requests. Second, the answer to your question is 'no', at least as far as the RFCs can state it. SIP REGISTER requests don't provide any guaranteed way for a registrar to recognize that the second request is from the same endpoint that sent the first request. Even if they arrived from the same IP address and port number, they still might be from different endpoints, if they passed through a network element that masked the real origins in some fashion. It is certainly possible for a SIP UA to include some sort of identifier in its REGISTER request that a suitably-programmed registrar could use to *replace* an AoR binding instead of adding a new one, but this behavior would not be specified by any RFC (and to some extent would not be RFC compliant, as you'd be changing the semantics of the REGISTER request). -- Kevin P. Fleming Digium, Inc. | Director of Software Technologies Jabber: [email protected] | SIP: [email protected] | Skype: kpfleming 445 Jan Davis Drive NW - Huntsville, AL 35806 - USA Check us out at www.digium.com & www.asterisk.org _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
