First off all, Merry X-mas ‘n stuff to you all ;) I’m using SER for a while now and I’m trying to get some answers to these questions: 1) Is there an indication on how many calls/s a reasonably simple server like a p IV 3.2 GHz / 1 gbyte ram can handle as a statefull proxy? 2) Would it be possible to use a stripped down ser to load balance a cluster of ser’s ? a. I want to build a scaleable, high available solution for minimal costs (as always :P) b. Reply’s need to come from the IP of the load balancer because of NAT traversal The internet -------→ Stripped ser -------------- SER Cluster | | Stripped Ser (standby) 3) Is it necessary for SIP messages within one call to end up on the same server within the cluster? IE if the loadbalancer sends the INVITE to ser_cluster_machine_1, which sends an PROXY AUTH Required, but the clients response ends up on ser_cluster_machine_2 what would happen? What would happen if the ser_cluster_machine_1 keeps waiting for an ACK for example? I think as a statefull proxy it would keep spitting out it's request until the reply ends up there by chance thru the loadbalancer Kind regards and best wishes, E. Versaevel