I’ve often been asked if a proprietary SIP PBX or an open source PBX should be utilized in my environment. Well, the answer to this question can be rather complex, depending upon your needs. There are reasons one may be beneficial over the other, as I have explained below.

An open source SIP PBX will normally interoperate with any PBX, proprietary or open, as long as it supports the SIP RFC 3261, the IETF SIP standard. The great thing about an open PBX is you can customize the software to suit your needs. There is also plenty of online help to get you going and even to help you once you have started. The only negative thing about the open PBX is it may be more difficult to get paid support.

A proprietary SIP PBX may not interoperate with another proprietary SIP PBX. Many times companies add proprietary SIP extensions to their code, which prohibits some interoperability with other proprietary SIP PBX’s. Proprietary PBX’s may not completely follow the IETF standard either, which also adds to interoperability issues, especially with other proprietary PBX’s. A proprietary PBX will often limit you to purchase other peripheral hardware just from that one vendor. The nice thing about proprietary PBX’s though, is they normally have a paid support staff to aid you when you need assistance.

In conclusion, the open source SIP PBX will be much less in expense compared to the proprietary PBX. There are no licensing fees and you do not have to sign contracts for support. As long as you have a knowledgeable staff and want to save on costs, the open source SIP PBX is certainly the way to go. A proprietary PBX is just that, proprietary, and often keeps your selection down to just the one vendor.