Switched serial interconnects are emerging as the architecture of choice for high-performance
computing and communications systems. They are fundamentally different from conventional
bus-based architectures in that they create dynamic, high-speed connections between
sources and destinations of data. They offer a high degree of modularity and scalability,
so designers can craft systems from common components that can serve anything
from a small enterprise to a large metro-area network. They can be made very robust,
incorporating any level of redundancy that an application requires. As the long
awaited convergence between telecom and datacom finally becomes a reality, switched
serial interconnect architectures are ideal for handling extremely large volumes
of packetized voice, video and data.
AdvancedTCA, developed by members of the PCI Industrial Computer Manufacturers
Group (PICMG), is the industry’s first high-performance open platform standard
delivering carrier-grade quality and robustness utilizing switched interconnect
technology. While applicable to a wide range of computing applications, it broke
new ground because it was designed from the bottom up to be suitable for Central
Office (CO) telecom-grade equipment. AdvancedTCA is the first open platform that
serves this market, which has historically known only proprietary, single vendor
Telecom is a Very Large Market
Despite the tough market conditions in the last few years, telecom is still an
enormous business by any measurement. The total worldwide telecommunications marketplace
in 2002 was $1994B ($2236B projected in 2003), according to a Telecommunications
Industry Association (TIA) study. That number is huge, and includes equipment,
but also takes into account engineering, installation, maintenance and everyone’s
A more useful number is the total global capital expenditure (CAPEX) for telecom
equipment. According to a recent RHK study, the total amount spent on equipment
was $215B in 2002. This is the total of $133B of wireline and $82B of wireless
equipment. RHK further estimates a CAGR of 7% per year through 2007. While this
growth rate seems modest by comparison to the recent years of “irrational
exuberance,” it is still healthy by any reasonable standard and is on
top of a very large base. If AdvancedTCA achieves only 10-20% market penetration
in the next 5-10 years, its dollar volume will completely dwarf older modular
platform standards like VME and CompactPCI.
Why an Open Standard for Telecom?
Telecom equipment manufacturers have traditionally designed and built just about
everything they deploy. There have been good reasons for this, as the quality,
reliability, performance and robustness requirements are so demanding that commercial,
off-the shelf equipment just hasn’t been good enough. During the years before
deregulation, there was little pressure on development costs or the time it took
to design and install equipment. Deregulation has changed all that.
Open industry standards, once they are accepted, tend to create a large number
of suppliers who must constantly innovate in order to remain competitive in both
performance and price. Suppliers typically concentrate on their core competencies,
providing specific platform elements without needing to supply everything.
Platforms based on open standards have additional appeal to telecom equipment
suppliers because commercially available hardware and software building blocks
can be used as the basis for many different applications (see “ATCA Platform
Building Blocks”, by Chuck Byers, p 35). This reduces the cost and time
required to bring a complete system to deployment or to upgrade an existing one.
Reusing these elements, instead of starting from scratch for each application,
keeps costs down. Systems based on common architecture building blocks also reduces
the time required to train installers and operators, and helps keep the size of
the spares pool down.
Telecom equipment suppliers are demanding open platforms for another simple reason:
the large engineering staffs that may have been present before the recent business
correction cycle have been downsized and they must focus on their core added value
(usually software), not wasting time re-inventing common building blocks.
AdvancedTCA was conceived with these needs in mind. Several major telecom companies
were involved with the development of AdvancedTCA since the beginning and have
provided many of the requirements.
computing networks are not just a requirement of the telecommunications industry.
Increasingly, all businesses rely on their data and their ability to exchange
information electronically. Large data centers are demanding the same levels
of reliability, robustness, maintainability and scalability that the telecom
companies have required for many years.
As the PSTN moves from a circuit-switched to a packet-switched infrastructure,
competition will emerge between providers of telecommunications services—including
the Local Exchange Carriers—and providers of Enterprise datacom services.
AdvancedTCA provides the high levels of performance and robustness required, and
it is reasonable to assume that suppliers of Enterprise equipment will adopt AdvancedTCA
in the coming years.
While much has been written in this journal and others about the specifics of
AdvancedTCA, a few features stand out from traditional, bus-based modular platforms
like CompactPCI and VME. They include:
- Switched serial interconnect architecture (no parallel bus like PCI) capable
of aggregate bandwidths in excess of 2 Terabits/second in a single chassis.
One advantage of a fabric architecture is that the failure domain can be as
small as one board or module. Failure of a single element need not bring down
the entire system.
- NEBS level environmental specifications, including shock, vibration, earthquake,
flammability, EMI, etc. AdvancedTCA does not use the familiar IEEE 1101-style
mechanics, but instead specifies a modular sheet metal construction that is
the norm in Central Office (CO) equipment. Cooling up to 200 watts per board
can be provided. Both 19” and 600 mm ETSI frame standards are supported.
- • A fabric-agnostic base design. AdvancedTCA currently supports 10
Gbyte Ethernet, Infiniband, StarFabric and PCI-Express. PCI-E Advanced Switching
will likely be added by the middle of next year.
- Sophisticated system management functions. AdvancedTCA is the first open
standard with this type of open system management architecture, and derivatives
are being used in other specification development efforts, including PICMG’s
CompactTCA and Advanced Mezzanine Card (AMC) specs currently under development.
Joe Pavlat has been President of the PCI Industrial Computer Manufacturers
Group (PICMG) consortium since 1995. He can be reached at Pavlat@picmg.org