Hi, Klaus! Thanks for your reply. In that case, is there any software that can be integrated with SER to function as SIP trunking? Thanks. Best regards, Roa Yu -----Original Message----- From: Klaus Darilion [mailto:klaus.mailinglists@pernau.at] Sent: Tuesday, July 10, 2007 2:34 PM To: roayu Cc: serusers(a)lists.iptel.org Subject: Re: [Serusers] How to configure Trunk capacity What do you mean by "trunk capacity"? The number of calls which may be sent to a certain gateway concurrently? If yes - you can't configure this in ser. ser is is transaction statefull, thus it does not count calls at all. Usually you just send the call to the gateway, and if the gateway is busy it will reponse with a certain response code. Then you configure ser to activate a failure to another gateway. regards klaus roayu wrote: