IP TRANSITION: THE CURRENT SITUATION
The growth of IP-based customer premise equipment (CPE) has helped businesses upgrade and converge network infrastructures and deploy exciting new IP-based features and capabilities while saving on recurring charges for analog lines and PSTN transport.
VoIP-based services (including IP Centrex and Hosted IP PBX) and equipment offer a range of new features otherwise unavailable, including voice-data integration, simple Web-based system management and desktop integration for presence-based features.
VoIP further allows service providers to make available new kinds of capabilities such as wireless-wireline integration, click-to-dial, teleworker/remote office applications and softphone support. To extend these next-generation carrier offerings most efficiently and seamlessly over the wide area to remote points, providers need to be able to directly connect, or "peer" over networks to IP PBXs at distant customer sites.
In a typical business network, the IP PBX serves as the interface to the LAN, enabling IP phones, PCs, conferencing devices, wireless equipment and other communications endpoints. At the same time, it also interfaces to the PSTN, enabling essential conversion of IP packets to traditional analog or digital signals and the reverse. This has typically been accomplished through adjunct IP telephony gateways, either at customer premises or in provider networks (see Figure 2, below).
But this packet conversion to TDM introduces delay (latency) that often degrades voice quality. Advanced IP-based signaling information and features meanwhile are often also stripped from the transmission by conversion, eroding the ability to deliver IP-based features. The bottom line: TDM routing of VoIP traffic is clearly an inferior, "Band-Aid" approach to next-generation communications that fails to support full VoIP capabilities.
Enabling IP PBXs rather to connect directly with VoIP service providers, eliminating the need for gateways and TDM traffic routing, is a far better approach, enabling the full capabilities of packet-based communications. To accomplish this peering, however, equipment and service providers must use common standards. Hence: SIPconnect.
While Session Initiation Protocol (SIP) adoption enables direct packet peering between compliant IP PBXs and compliant VoIP service providers, SIPconnect offers a well-defined method for applying SIP to connecting provider networks with IP PBXs. Figure 3, below, illustrates direct IP peering.
