|
 |
 |
To SIP or Not To SIP
By Ken Osowski |
Is it Better To Leverage the Market or Fight It?
For prepaid service providers, the future is now. New vendors are entering and incumbents are aggressively expanding the prepaid market - with new low cost solutions - and building services and revenues by leveraging the increasingly-pervasive IP infrastructure and the Session Initiation Protocol (SIP) services ecosystem. In doing so, they’re accessing a long-term opportunity and business model that’s completely inaccessible via traditional TDM networks.
The Opportunity
Large carriers such as XO, Interoute, and Level 3 are providing wholesale IP voice services via SIP-enabled components that perform functions such as local number access and IP-to-PSTN call conversion. This “SIP trunking” provides comprehensive PSTN interconnection – and in the near future, service interworking – creating the compelling global arbitrage opportunity for Prepaid Service Providers to economically address the market with prepaid services, without TDM-based switches or PSTN-to-IP media gateways.
This architectural approach decomposes the old TDM service model in much the same way that the PC and Server model decomposed the ‘60s era mainframe. Hardware and software components have distinctive functions, and their interfaces are based on open communications protocols: SIP, MGCP, Real-time Transport Protocol (RTP), and commercially available computer systems, databases, and web servers. Service logic is independent of the hardware and runs on what is generically called an application server. An XML-based Service Creation Environment (SCE) simplifies the generation of services, and keeps them independent of the underlying hardware platform. This enables infrastructure expansion and growth, as well as service evolution/innovation and the ongoing freedom to incorporate new best-of-breed services and components.
The key components to realize this opportunity are the service delivery platform and the session controller. The service delivery platform consists of 1) an application server to run the prepaid service logic, 2) an IP media server to play prompts and collect DTMF digits and 3) a database management for storing subscriber and call detail record information. Some service providers also incorporate a web server to allow subscribers to access and manage accounts online. As with any growing market, SIP-based service delivery platform vendors have recognized and are leveraging the relatively new SIP trunking market, and are providing comprehensive suites with attractive entry cost points and incremental expansion potential.
You Say You Want An Evolution
The biggest single reason this new SIP trunking model will continue to grow and create service provider opportunity is that SIP delivers the software control over features and integrations that proprietary systems cannot. It also lets service providers leverage best of breed innovations that lower service costs, such as the session border controller, an extremely efficient, economical replacement to old least cost routing of programmable TDM-based switches.
In the future, such flexibility could mean a great deal more. In the wake of an unprecedented series of natural disasters around the world, FCC Chair Kevin Martin is now calling on the U.S. Government and its key vendors to “take full advantage” of IP-based technologies to enhance their networks. How this will affect service provider requirements to re-shape services on the fly, accommodate emergency call re-routing, sustain subscriber access during sharply reduced network capacities, etc. is anyone’s guess. But early discussions raise the potential for new ‘evolve or die’ mandates for all levels of the public voice service delivery chain.
The Time Has Come to Ditch the Switch
In any business, and especially in competitive markets, you’ve got to know when to hold ‘em, and know when to fold ‘em. For the last 15+ years, service providers have used TDM-based programmable switches to offer add-on voice services. Because the Class 5 switches were not easily or cost effectively upgraded, overlay networks were built using programmable switches to support “enhanced” services, a decidedly pricy and non-flexible business model. Moreover, in the TDM switch environment, enhanced service applications could work only with ONE programmable switch product, which locked the service provider and application vendor into a rigid relationship.
The first step forward in the IP switching evolution came in the late ‘90s with the advent of the media gateway and softswitch, which formed an intermediate step towards today’s VoIP networks by creating the first real bridge between PSTN and IP networks. This allowed service providers to play in both networks. Early deployments of small gateways were used for international voice traffic arbitrage, soon followed by larger gateways used for VoIP trunking, acting as a “Class 4” switch.
A key advantage of the media gateway is that it made enhanced services totally independent of a manufacturer’s switch hardware for the first time, via the use of the SIP protocol. SIP application servers emerged, and this server-based model cleanly separated service logic from the switching fabric.
SIP application servers gained immediate market traction by providing traditional enhanced services such as prepaid calling card and audio conferencing to TDM-based subscribers. The media gateway and softswitch connected to the application servers using IP protocols, while subscribers remained connected through PSTN-based phones on the TDM side of the media gateway. Today, there’s fast-growing market demand for SIP-based, primary line VoIP services such as those from Lingo and Vonage. Along with these new services, (as with any voice service), “prepaid” is an attractive option for many subscribers as well as a way for every service provider to expand his customer base. SIP application servers are delivering these services, and providing a rapidly configurable, low cost solution for the successful carrier business models of the future.
The entry to opportunity provided by SIP-based solutions renders the TDM-based programmable switch for voice service delivery the equivalent of the dedicated word processor, circa 1980s. The application’s useful, but the dedicated hardware’s increasingly obsolete.
Like the PC, SIP-based solutions are driving new prepaid market opportunities based on flexibility, reliability, redundancy, economy and the ability to evolve.
They’re also the reason that profit-driven providers are bypassing programmable switches and other SIP-less gear, consigning them to the same technology closet that now houses those Wang systems, ‘60s era mainframes, BetaMax decks, 8-Tracks and sundry turnkey, vendor-locked products. Profit-driven providers avoid it, but if you do decide to go there, please be nice to those folks standing guard. They’re from the “Flat Earth Society.” As they proclaim their impending return to relevancy, just nod politely. Then, back away quickly and re-join the market.
Ken Osowski is VP of Product Management for Pactolus Communications Software, an IP service applications provider. He can be reached at 508-616-0900 ext. 328 or kosowski@pactolus.com.
 |
|
.gif)
