As service providers build out their broadband packet networks to offer enhanced triple-play services, telecom OEMs (TEMs) are working overtime to provide the equipment needed to deploy those services. Historically, TEMs have built this equipment from the ground up by using proprietary platforms. A growing number, however, is finding it increasingly difficult to deliver homegrown equipment in a timely, cost-effective fashion.
To enhance their competitive position, many TEMs are now utilizing open architecture platforms based on industry specifications and standards, which make it easier for them to outsource their equipment design and keep pace with the latest technology. Open platforms reduce the time and cost associated with designing and manufacturing telecom equipment, savings that are ultimately reflected in reduced capital expenditures for service providers. They also facilitate the design of modular, flexible telecom systems that are easier to scale, upgrade, service, and maintain, benefits that are ultimately reflected in reduced service provider operational expenditures.
Several organizations are working to define open platform standards for hardware, software, system integration, and high-availability design, including the PCI Industrial Computer Manufacturers Group (PICMG), the Linux Foundation, and the Service Availability Forum (SAF). Building on these baseline platform standards, industry groups such as the SCOPE Forum and the Communications Platform Trade Association (CP-TA) are also working on equipment profiles, application frameworks, and testing services that guide all phases of component selection, software development, integration, and verification. Meanwhile, the Mountain View Alliance (MVA) is emerging as an umbrella organization for providing system guidance, coordination, and marketing for all of these organizations.
Modular Architecture One of the first open platforms to pique the interest of equipment providers was CompactPCI, particularly after the addition of telecom-friendly features like hot-swap, a dedicated telephony bus (H.110), Ethernet-based packet transport (PICMG 2.16), and Integrated Peripheral Management Interface system management. More recently, however, ATCA has emerged as the dominant open platform for telecom infrastructure applications. Aimed squarely at next-generation packet networks, ATCA provides advanced features such as a high-bandwidth switched fabric, remote system management for individual modules, hot-swap, and provisions for implementing high-reliability architectures, all common requirements in telecom designs.
The Advanced Mezzanine Card (AMC) specification increases the modularity of ATCA systems, enabling OEMs to customize AdvancedTCA carriers with application-specific CPU, signal-processing, I/O, networking, and mass-storage capabilities. An ATCA card can carry as many as four AMC modules, giving designers a variety of potential configurations from a single card. And like an ATCA blade, AMC modules allow for remote system management and hot-swap for individual modules.
Building on the success of ATCA and AMC, PICMG has also developed a small-form-factor chassis specification targeting telecom applications with tight space and cost constraints. Known as MicroTCA, this specification defines a hot-swappable, switched-fabric chassis that can accept AMC modules directly, without the need for an ATCA carrier. With MicroTCA, designers can leverage not only the installed base of AMC cards, but also the same switched-fabric, transport, and management protocols.
The software foundation for telecom systems starts with the operating system (OS), typically carrier-grade Linux, which provides advanced high-availability features such as failure detection, fail-over, and hot-swap management (Fig. 1). The middleware extends the OS, providing advanced interprocess communications, event logging, fault management, and network management services that speed the development of portable, scalable applications.
The hardware platform interface adapts the software for a particular hardware architecture, while the application interface specification (AIS) layer couples applications with the system software platform. Application software sits atop this hardware/software platform, providing the vendor-specific service enhancements that TEMs use to differentiate themselves from their competitors.
Open Standards Follow System Structure Efforts to develop open standards and specifications for building telecom systems follow the same basic structure as the system design. Each layer requires its own set of documents, with a host of industry consortia developing those requirements. An entire standards and specifications ecosystem has emerged from this combined effort. Some groups address the needs of a specific layer. Others address the interfaces between layers, testing, and overall coordination.
The telecom standards ecosystem begins with the open platform building blocks, including the interfaces between those blocks (Fig. 2). Several organizations are involved in the definition of open platform standards.
PICMG is responsible for hardware specifications such as ATCA, MicroTCA, and Advanced Mezzanine Card. All three hardware specifications are now well established, but PICMG’s efforts aren’t over. Currently, the group is defining specifications for a ruggedized version of MicroTCA that addresses the needs of harsh working environments.
It also recently completed the hardware platform management specification (HPM.1), which will allow firmware downloads. A change in form factor for ATCA, ATCA300, is undergoing definition as well. And, change notices for ATCA and AMC.1 PCI Express are under way to resolve issues and upgrade performance specifications.
On the software front, the Linux Foundation continues to develop standards for a carrier-grade, Linux-based operating system. Meanwhile, the Service Availability Forum (SAF) is tackling the specific needs of high-availability system design, defining the management functions and interfaces that building blocks must offer. OpenSAF has assumed stewardship of an open-source implementation of SAF’s application interface specification (AIS).
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