Media gateway developers, manufacturers and service providers face a daunting task: looking for ways to lower cost and meet time-to-market demands as consumers' insatiable desire for more advanced applications accelerates at an unprecedented pace. Nowhere is this challenge more evident than in the digital signal processor (DSP) development community where cost, time-to-market and shelf life are the mantra to usher media gateways into the future.

Media gateway vendors are continuously challenged by new network requirements that demand advanced voice signal processing, video support and more stringent quality metrics, while DSP vendorsmust demonstrate a broad experience in both voice and video processing in order to deliver on the promise of better quality.

Initially, media gateways, based on industry standards, were designed using generic DSPs for a specific purpose--Voice over Internet Protocol (VoIP). As the market grew, DSP vendors began to provide system-on-a-chip (SoC) solutions that included all the necessary hardware to perform TDM-to-IP (time-division multiplexing to IP) or IP-to-IP conversion. This often involves having the right balance of performance-to-power consumption and the appropriate physical input/output (I/O) interfaces.

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Standards are important to ensure interoperability between systems and to help drive down cost by offering a common language between vendors and developers. The large number of standards for voice and video codecs, for example, is the main "raison d'être" of media gateways. Media gateways serve as the universal translators between many of these different standards, and therefore, as new standards are developed and deployed, the gateways must also evolve and provide the platform for new and emerging technologies and applications. This accelerated technology development has caused a shift in the way media gateway and DSP engine developers prepare for the future.

VoIP is not just VoIP anymore

About eight years ago, the industry began to see the emergence of complete media gateway products, offering both hardware and firmware components, which enabled original equipment manufacturers (OEMs) to focus on upper-layer application software. These products have matured over the past decade to a point where the underlying DSP technology has stabilized and the basic feature set is well understood.

While the basic TDM-to-IP media gateway market has matured, a slew of new requirements--to support not only pristine quality in VoIP but also emerging applications--have appeared. The emergence of session border controllers (SBCs), fixed mobile convergence (FMC) and video communications, as examples, have created specific design challenges.