Iñaki Baz Castillo wrote:
2008/10/13 Jiri Kuthan jiri@iptel.org:
The thing here is that actually a load-balancer vendor is free to build stuff his way -- he is not compelled to build a proxy or B2BUA and go to some certification authority, he is supposed to build something that load-balances well. I'm intimately aware of some load-balancers that are close to being a kind of "transparent proxy", which is just fine: it doesn't put itself in signaling and it handles routing by state table.
Well, but what I mean is that the vendor needs, not just a custom LB which doesn't add "Via" header, but also devices behind the LB (other proxies or gateways) being not SIP compliant in points 18.2.1 & 18.2.2 of RFC3261.
We do have garden variety proxies behind our load balancers and they are not aware of the presence of those load balancers. The trick is to give them all the same IP and have the balancers work one layer below. From the IP perspective, they are all one. Or something.
Regards, Martin