Sweden-based Ingate produces session-initiation protocol (SIP)-capable firewalls and SIParators -- a device that plugs into an existing firewall to seamlessly enable SIP -- for enterprises that want the time and money saving benefits of SIP-based real-time communications including presence, instant messaging (IM), VoIP and conferencing.

SIP, or Session Initiation Protocol, is the Internet Engineering Task Force (IETF) signaling protocol that allows interoperable real-time communications regardless of who is providing the service. Providers including Microsoft, AOL, AT&T, MSN, Yahoo, Cisco Systems, Pingtel and CommWorks are either already offering or are developing SIP-based products and services. Some predict it will only be a matter of time before SIP is for real-time communications what HTTP is for the Web.

Because SIP is a new protocol, though, existing firewalls currently block SIP media streams. Ingate's technology allows SIP to interoperate with existing installed firewalls.

Ingate's suite of firewalls and SIParators are available in a range of models to meet the needs of the entire enterprise market. All include a SIP proxy and a SIP registrar, support NAT and PAT and have TLS support for encrypted SIP signaling, which means that instant messages are automatically encrypted, eliminating IM security concerns.

Bob Woods is the managing editor of InstantMessagingPlanet.