Open source group posts free IP PBXb

  • Tim Greene (Network World)
  • 17 January, 2005 14:00

An open source group has posted free Session Initiation Protocol-based PBX software that lets businesses create their own phone switches from standard Linux servers -- but drawing business customers to the technology could be an uphill effort.

Called sipX, the PBX offering is compatible with SIP phones and media gateways that can change IP voice to traditional TDM voice and vice versa so calls can be switched onto traditional phone networks.

SipX was written by SIPFoundry, whose goal is to encourage businesses to develop interoperable SIP products so end users can readily take advantage of SIP features, such as presence, without tweaking the equipment they use. The organization considers itself a developer community where members can contribute to writing open source code, similar to the Linux development community.

Development of sipX parallels similar efforts that produced Asterisk free PBX software, backed by equipment vendor Digium. Asterisk was released last September.

While free software might be attractive to some, it is unlikely to become a major force in large businesses. "It has potential for small organizations or homes, but it's unlikely to make a significant dent in the enterprise," where customers want more than just a PBX, says Paul Strauss, a research manager at IDC. "You do need support; you do want assurances of quality; you do need to see what's going on inside it; you want the vendor to sell you phones."

SIPFoundry's key founder, PingTel, says it hopes that businesses interested in the open source SIP software will buy it along with supplemental software tools and support from PingTel, using the same model Red Hat uses with Linux. PingTel sells PBX support services wrapped around a version of sipX.

Sterling National Bank & Trust says it likes the idea of open source PBX software, but chose to acquire it through PingTel and hire the vendor to support the bank's phone system rather than go it alone. "We're probably not that brave," says Eliot Robinson, the bank's executive vice president. "We want somebody to call on when we need some help to configure the system or to support some users' specific requests."

He says he also likes the idea of an open source development community that he believes will innovate new features quickly. "It's good to know there's multiple developers out there enhancing the system," he says.

PingTel's share of the IP PBX market is too small to count, Strauss says. According to IDC, IP PBX technology is driven not by traditional circuit-switched PBX vendors but by new vendors, and that doesn't mean start-ups. 3Com and Cisco Systems, which have quickly dominated corporate IP voice, are considered new vendors because they only leapt into PBX sales with IP offerings. Avaya, Nortel Networks, Siemens, NEC and Toshiba -- the traditional PBX leaders -- all have revamped their offerings to embrace IP.

What might give hope to the open source effort is the current small size of pure-IP PBX sales At the same time, Cisco dominates in sales of this category, which will be formidable competition, says Matthias Machowinski, directing analyst for enterprise voice and data at Infonetics.

Also available for download from SIPFoundry is reSIProcate, a SIP software stack around which developers can build SIP-enabled gear. Commercial products already using reSIProcate include Jasomi Networks's session boarder controller that aids moving VoIP calls through firewalls, Xten Networks Inc.'s softphone and call-agent software, and Jabber's presence-based messaging software.

SIPFoundry also is developing a set of SIP interoperability tests that vendors can run on their own gear to better ensure it will be compatible with other vendors' equipment when they get together at interoperability bake-offs, says Robert Sparks, the president of the SIPFoundry board and CTO at Xten.