US telecoms and network specialist Remwave has launched Mac2Phone, its IP-based telephony service for Mac OS X 10.2.

Remwave CEO Nikolai Manek said: "With we’ve launched our support and commitment to the OS X platform. As a perfect system for Java applications we see huge opportunities in developing for it."

The solution integrates modern voice-over-IP (VOIP) telephony solutions, such as the rapidly emerging SIP (Session Initiation Protocol) and H.323 protocols.

Manek added: "Now the Mac community can make free phone calls between Macs running OS X or to PCs running the Buddyphone software".

Industry observers believe Mac2Phone is the closest yet to the long-rumoured iPhone solution for enabling VOIP telephony on Macs. Remwave is a well-established global Internet telephony service provider with clients among cable and telecommunications companies worldwide.

Critical to the development of robust IP telephony solutions is the move to a digital, rather than analogue infrastructure. However, SIP and, to a lesser extent, H.323, offer the facility to access traditional analogue telephone lines – with the addition of special switching equipment.

Two versions of Remwave's OS X-supporting software are available: Mac2Phone Basic is the company's freeware version, although registration is required, while Mac2Phone Pro ($19.95) offers additional functionality.

Mac2Phone Basic offers free calls with "excellent" voice quality over the Internet from any Mac-to-Mac or -PC, the company claims. It also offers the facility to talk to people using Remwave's SoftPhone or any SIP-enabled IP Phone "without costs".

The solution lets users call mobile or established analogue telephones at low rates, though users need to set-up an account to take advantage of this feature.

Users can also receive calls from mobile, fixed analogue phone-lines, or SIP-based telephones. Users must be running OS X 10.2, and have a microphone and speaker installed.

Mac2Phone Basic maintains a list of all calls placed. In use, broadband connections have the advantage – the company warns that slower modem connections are best used for Mac to computer calls. Calls to regular analogue telephones require the equivalent of a cable or ADSL modem. The solution also supports SIP and AIM-based messaging and creates and manages searchable buddy lists.

SIP is a signalling protocol for Internet conferencing, telephony, events notification and instant messaging. The Internet Engineering Task Force's (IETF) Multiparty Multimedia Session Control working group has been developing SIP since September 1999. Apple has not commented on whether it plans to adopt the open standard in its products.

Additional features are likely to emerge as SIP-supporting networks are rolled out worldwide. This is very likely to occur, as Microsoft recently introduced SIP support as part of the Windows Messenger application of Windows XP.

Despite Microsoft's support, SIP adoption has been hindered by the WorldCom-led wave of financial insecurity within the telecoms industry.