[Serusers] Serving multiple domains

Hi List, We have a few local domains that we will be using SER act as a proxy and to protect our gateway. In the near future we will also be providing PSTN breakout for other SIP domains that are not on our proxy. What is the best way to allow traffic from certain know SIP domains out through our gateways? I've thought about having users authenticate to our proxy, but this could get very complex and messy serving multiple local & remote domains. Other option is just to allow traffic through from the trusted domains I guess. One last question, is any one familiar with the Cisco AS5300? How do you go about locking it down so that only authorised users can pass calls out onto the PSTN? We have a number of Vega 100's that have the option of only allow proxy invited calls. Is there something similar on the AS5300 or would that have to do authentication aswell, AAA ? I know that this question is slightly off topic, but with it being related I thought someone my be able to answer my question. Many Thanks, Alan ------------------------------------------------------------------------------------------------------- This email, and any files transmitted with it, is copyright and may contain confidential information. The contents are intended for the use of the addressee(s) only. Unauthorized use may be unlawful. If you receive this email by mistake, please advise sender immediately. The views of the author may not necessarily constitute the views of Telco Electronics Limited. Nothing in this mail shall bind Telco Electronics Limited in any contract or obligation. Telco Electronics Limited 6-8 Oxford Court Brackley Northants NN13 7XY Tel 07000 701999 Fax 07000 701777