After years of mounting expectations, the worldwide VoIP market is experiencing significant growth as service providers, businesses, and consumers realize the deployment benefits of converged, packetized voice and data services. Designers are rapidly adding these mixed-media capabilities to what have heretofore been islands of voice-centric or data-centric networks.
In the residential market, the focus is on integrating basic voice features into a single packet-based gateway. Meanwhile, enterprise class designers are focusing on adding full voice quality and secure VPN data routing into converged mixed-media platforms. Carrier class systems also can benefit from this new mixed-media architectural model. In all three cases, the advent of open source voice applications has stimulated important new opportunities, providing designers with a head start on basic convergence features, and a foundation upon which they can add customized features and capabilities while optimizing quality, performance, and cost, with faster time to market.
The open source model including the ability to run open source and third-party applications and access a variety of hardware integration options enables manufacturers to cut development costs and execution risks while accelerating time to market for broader product offerings with expanded feature sets, improved real-time performance and scalability. At the same time, manufacturers also can leverage their development investment across a wide range of residential, enterprise, and carrier applications.
Design Examples for Small Businesses
VoIP migration has now reached the doorstep of small businesses as an exciting alternative to expensive private branch exchange (PBX) technology. The same concept illustrated by VoIP in the home applies to VoIP-based PBX technology in the small business environment with minor complications. First, the enterprise gateway has to support four or more phone lines, fax machines, and point-of-sale terminals. Additionally, voice quality and the telephony gateway application have become major issues. For the small business, even a small PBX is out of reach from a cost perspective. In contrast, a combination of off-the-shelf and open source VoIP technology building blocks combine to produce an elegant telephony solution.
The main required building block is the telephony application that runs the entire system and interacts with the telephony provider. Up until now, PBX vendors have kept their telephony applications proprietary and charged high fees for service contracts. The open source revolution disrupted this business model when the Asterisk PBX software solution finally was released to the public. Asterisk is an open source PBX and Internet Protocol (IP) PBX telephony application that offers both traditional and next-generation network features such as Session Initiation Protocol (SIP)-based IP telephony or peer-to-peer directory services. Installing and maintaining Asterisk requires some effort but is justified given the savings in the operating expense.
The other required building block is the hardware for running Asterisk. The standard hardware is an off-the-shelf PC with the desired telephony adapters. Asterisk runs with no modifications on a standard PC; however, this configuration may not be ideal when voice quality, scalability and reliability are key concerns. When special requirements exist in these areas, designers need to consider using an embedded media processor from companies that supply semiconductor devices to the telephony industry. In this application, Asterisk requires some modifications to offload the media processing to an embedded device. The latest embedded media processors offer direct access to off-the-shelf open source applications and dont require extensive software redesign, opening up a host of new opportunities for designers.
Working with Embedded Media Processors
Todays latest voice and data convergence platforms offer, on a single chip, the horsepower of two independent CPUs that share a common SDRAM and yet independently handle signal and packet processing. They also integrate a flexible high-performance encryption engine, all security and other VoIP features into a single device, and include a variety of high-speed interfaces. Their extensive software suites support all wireless and wireline voice/fax codec standards, echo-cancellation technology, and IP protocols and modulations. Additional functionality can be included through software upgrades. They run off-the-shelf open source Linux and Linux applications, and use standard open source development tools.
There are several examples of open source VoIP applications where the use of an embedded media processor offers significant advantages. The first is a company that has already invested in a PBX and wants to conserve its capital investment by moving the PBX onto a VoIP network. Another example is a small company that has invested in a small stand-alone telephony box that provides Internet access, routing functionality and IP PBX capabilities. In each of these examples, an open source VoIP application supported by an embedded media processor yields the desired voice quality, scalability, and reliability.
Multiple criteria should be considered in selecting a media processor platform. First, dual processor designs offer the advantage of an architecture with deterministic carrier grade voice quality and the ability to scale from data-only applications to full packet telephony capabilities operating on up to 32 complex voice channels. Secondly, the device should have a security engine for voice security and VPN connections. Thirdly, the device must have an extensive and programmable software suite, and deliver a sophisticated open source processing system for a complete mixed-media processing solution on a single chip. And finally, the system-on-chip (SoC) should not require extensive software redesign when integrated with an open source application, which eliminates the risk of any impact on the real-time functional blocks like voice processing.
The Asterisk Open Source telephony application provides an outstanding foundation for realizing the benefits of SoC media processors. It is now a mainstream application that is allowing businesses around the world to benefit from the VoIP revolution at a fraction of the original cost using traditional approaches. Any possible voice quality and scalability shortcomings of the Asterisk telephony application are easily overcome by augmenting the system architecture with single-chip media processing devices. Asterisks modular architecture was designed to allow the straightforward insertion of media processor devices, enabling systems to guarantee the voice quality that is absolutely required in a business setting.
Emerging Developer Ecosystems
Along with the availability of media processors and open source software applications have come comprehensive new development ecosystems consisting of multiple vendors collectively supporting a common open source hardware and/or software platform. These ecosystems enable VoIP system designers to quickly and easily integrate single-chip VoIP media processors with products and services from a growing network of participating hardware, software and contract manufacturing companies.
Open source development ecosystems give both new market entrants and established voice equipment players alike, the necessary resources with which to quickly create baseline designs and then value-add their own customized features and capabilities, as desired. Design options range from complete turnkey solutions to flexible designs that can be easily customized and differentiated for specific market segments. Basic elements of the development ecosystem include a processor platform optimized for open source VoIP applications, a rich library of open source and third-party applications, and a comprehensive development/manufacturing ecosystem.
New Applications, New Profit Opportunities
The open source approach differs dramatically from traditional component-centric approaches that require extensive internal development work on the part of the equipment manufacturer. In contrast, open source initiatives create a robust and significantly more comprehensive solution while offering numerous advantages to customers and partners, alike.
The design possibilities are broad and growing. For instance, a vendor can integrate a customized API channel module for a media processor into the Asterisk Open Source PBX application, enhancing the time to market advantage of enterprise equipment customers designing open source-based PBX systems. Another vendor might integrate session initiation protocol (SIP) software into the media processor, creating an enhanced system-on-chip voice processing solution for enterprise PBX, gateway, and voice-enabled router equipment. A third vendor might integrate a media processor into a family of voice-gateway modules, allowing equipment manufacturer to quickly add robust voice services to existing router, enterprise PBX and carrier gateway equipment.
The more comprehensive the development ecosystem including software application developers, design services partners, and turnkey ODM solutions providers the richer the design opportunities, and the faster the time-to-market. Increasingly, raw silicon performance isnt enough. Todays open source media processors with built-in encryption engines are capable of processing up to 32 channels of highly secure VoIP and routing data at up to 150 Kpps, with up to 60 Mbps of throughput for highly secure virtual private networks. While it is possible to find better performing SoC processors, this means sacrificing the ability to support off-the-shelf open source software, and the result is much more costly software rewrites and customization requirements. Indeed, it is increasingly important that designers consider the accompanying software development and/or customization, which is substantially streamlined through the use of open source software run on an embedded media processor and supported by a
comprehensive development infrastructure and ecosystem.
VoIP is here to stay. The technology is now in widespread use at millions of homes worldwide, and the open source model is poised to further accelerate its adoption. Everyone benefits. Manufacturers increasingly can leverage developer ecosystems and take advantage of reduced designs costs/cycles for modular and scalable products. Open source vendors benefit from the synergies inherent with offering a holistic and coordinated multi-vendor approach to VoIP equipment design based on a foundation of open source applications. Service providers benefit by diverting voice call profit from traditional operators. And finally, users benefit by having lower operating cost and access to next-generation applications that better integrate communications with the overall business process. IT
Diya Soubra is the director of marketing for the enterprise product line and manages the European Engineering Design Center for Mindspeed Technologies. For more information, please visit the company online at www.mindspeed.com.
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