Impact of Media Gateways on Voice Solutions

This is the latest in a series of posts on how voice development has been moving from hardware to software centered models. In my last post, we reviewed the classic approach to developing voice-centered solutions, which typically utilized voice boards. In this post, I’ll review how media gateways helped change the model.

In the classic voice model, the voice board often was used both for voice processing and to connect to a phone network, which might be either digital or analog. When Voice over IP (VoIP) began to emerge, new options became available for voice solutions. In the early days of VoIP, the H.323 stack was used to connect to IP networks, but the Session Initiation Protocol (SIP) got some crucial support in the 2000-2001 time frame from Microsoft and the Third Generation Partnership Program (3GPP), the leading standards organization for mobile phone networks. Within a few years, voice developers began to add SIP to their development capabilities. This had multiple implications.

Let’s look at some business side drivers. After the dot com crash and the related “Telecom Downturn,” which decimated the ranks of engineering staffs of the large vendors known as The Equipment Manufacturers (TEMs), these companies were looking for ways to reduce the amount of hardware in their solutions. In the classic voice solution, the voice board processed media and also connected to the circuit-switched networks. When SIP became popular, many of the TEMs started saying they wanted to move away from the hardware business. Some of these companies started processing media as part of their voice applications and others continued to rely upon voice boards for this processing.  In either case, if they outsourced the connection to the network to another box, they could reduce the number of hardware dependent elements in their solution and simplify the process of building and shipping their solutions.

Enter the Media Gateway. As the application developer included SIP in their solutions, they could connect to a media gateway via SIP and then let the media gateway take over the role of connecting to the existing circuit-switched network. This had been possible before SIP with H.323, but SIP offered much more flexibility for doing the complex call processing needed by the voice developers and continued to gain market momentum. In turn, various hardware companies started building purpose-built media gateway appliances to connect to digital or analog networks. The gateways supported the most common networks such as ISDN first, but eventually some gateways got more sophisticated and added Signaling System #7 (SS7) support as well.  This decomposition  of the voice solution offered benefits for both types of vendors. The solution vendors could start their move away from hardware and focus more on software, whereas the media gateway vendors were able to specialize in connections between SIP and the circuit-switched networks. Each type of company could specialize in their area of expertise and the solutions providers could add value to their solutions by buying best-of-breed media gateways.  Since the network protocols were standards-based,  the gateways needed to have robust standard protocol implementations and this helped create a competitive market for media gateways.

As a result, solution developers took another step along the path of reducing their dependency on embedded hardware, since they could now outsource the network connection to a media gateway.  In the next post, I’ll talk about developments in IP-based media which continued the evolution toward software-based voice applications.

If you participated in the evolution described here, please feel free to weigh in with your comments. If you’d like to explore strategies on how to evolve your company’s solutions to meet customer needs, you can reach me on LinkedIn.