Your right, of course. Using DNS SRV for reliability has its limitations. The idea is to combine various methods to come as close as you can get. I assume that your statement is based on how RFC3263 specifies handling of outbound server going down mid-dialog?
g-)

Ritesh Jalan wrote:
Hi
 
DNS SRV is a Load Balance system, How it can be a fail over.
 
Only for call initialisation a UAC will search for DNS SRV records, but after the the call starts, if First server (From which call is beaing initiated) goes down then thebye message will not go to second server
 
 
 
 
 
net4.in
Ritesh Jalan
Senior Engineer - Business Solution
Net4India Ltd.
D-25 Sector - 3
Noida - 201301
India
Tel: 91-120-5323500
Mobile: 91-9818616329
Fax: 91-120-5323520
MSN: ritesh_jalan@hotmail.com
URL: http://www.net4.in
----- Original Message -----
From: samuel
To: G. Jacobsen
Cc: seruser List
Sent: Friday, July 07, 2006 2:00 PM
Subject: Re: [Serusers] Global Failover Server

Following lines are an extract from the SIPit preliminary report regarding supported DNS features in current implementations:

>160 people from 16 countries attended SIPit 18 with 73 different SIP implementations:

>Full 3263                             25
>3263 (no naptr,SRV on)      13
>A only                                  22
>IP only (no DNS)                   9

Which gives a percentage of 38/73 supporting SRV records, so more or less half of the implementations supports this type of load balancing.

This value should be used with care because implementations include both UAs and proxies/redirect/* servers.
I can also say that a higher percentage of desktop SIP phones supports DNS SRVs, but since it's just my impression from the ones I have touched I can not assure nor give a percentage...

Hope it helps,

Samuel.



2006/7/6, G.Jacobsen < g_jacobsen@yahoo.co.uk >:
Samuel,
 
Do you happen to know what percentage of UAs out there are really "Compliant" UAs  ?
 
My impression so far regarding SRV DNS records is that they are theoretically a nice feature but unfortunately almost useless since one needs to cater for those non-compliant UAs anyway. I would love to be convinced of the contrary.
 
Can anyone supply real usage figures regarding compliant/non-compliant UAS ?
 
TIA
 
Gerry
 
 
 
-----Original Message-----
From: serusers-bounces@lists.iptel.org [mailto: serusers-bounces@lists.iptel.org]On Behalf Of samuel
Sent: Donnerstag, 6. Juli 2006 14:52
To: Ritesh Jalan
Cc: seruser List
Subject: [Bulk] Re: [Serusers] Global Failover Server


Look at RFC 3623.
Cofigure two SRV entries in your DNS, one pointing to the UAS SERver and another to the UK server. "Compliant" UAs will try to contact the other proxy upon failure of their current one.

Samuel.

2006/7/5, Ritesh Jalan <ritesh.j@net4.in>:
Hi All
 
Pls. guide me how can we implement failover on SIP Server located globally, Like one server in USA another in UK.
 
 
 
Ritesh Jalan
Mobile: 91-9818616329
MSN: ritesh_jalan@hotmail.com

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