SAN JOSE, Calif. -- Intel Corp. will formally announce Tuesday (Sept 30) that version 1.0 of its Advanced Switching specification for PCI Express is finished. Seven companies are backing the spec by becoming board members of a new Advanced Switching Interconnect (ASI) special interest group.
Agere, Alcatel, Huawei, Intel, Siemens, Vitesse and Xilinx are joining the ASI SIG. Rajeev Kumar, an Intel initiatives manager who will become president of the SIG said other active members of the Arapaho Working Group that defined AS " including EMC Corp., IBM and Sun Microsystems " may join by the end of the year when the group formally convenes.
The group is positioning AS primarily as a backplane link for wired and wireless comms access and network edge gear as well as some server and storage systems. That position is meant to distance AS from alternative technologies such as HyperTransport aimed at chip-to-chip links and RapidIO that recently expanded its focus to include backplanes.
"The primary target is the backplane, but we do see AS being used as a chip-to-chip interconnect on line cards where there are multiple network processors or DSPs. And we're seeing a strong amount of interest for AS in storage systems," said Kumar.
Kumar reiterated Intel's stated plans to put AS links on a Pentium-class chip set and on members of its IXP network processor family that will sample in 2005. Vitesse and Agere are also expected to put native AS links on some of their network processors and switch fabric chips.
By contrast, Motorola is already putting RapidIO links on a variety of its processors. Other RapidIO backers including Analog Devices Inc, Agere, IBM and Texas Instruments are expected to follow suit.
For its part, AMD, Broadcom, Nvidia and PMC-Sierra among others are already using HyperTransport on some of their processors and chip sets.
HyperTransport and to a lesser extent RapidIO have a market leap on AS because those interconnects are already on shipping products. Indeed, International Data Corp. estimates as many as 30 million HyperTransport ports will have been shipped by the end of 2003 based on the interconnect's use in dual-ported Microsoft Xbox game consoles, Apple G5 Macs, AMD Athlon-based PCs and a handful of other products. Motorola and its partners began shipping components using RapidIO earlier this year.
Kumar said Intel will leapfrog its competitors quickly because it is committed to shipping the baseline PCI Express interconnect on all new PC chip sets starting in 2004."That represents some 200 million ports doubling every year for the next two years. That alone dictates the costs for AS will go rapidly down," said Kumar.
AS is a new protocol for handling peer-to-peer packet data riding on top of the physical layer specification of PCI Express. Both RapidIO and HyperTransport recently made announcements about enhancement to their protocols for handling packets in control and data plane operations in comms gear.
To date, only the AS spec has been written in a way to take into account use in a backplane. For example, AS supports 2- Kbyte packet sizes while HyperTransport handles 256-byte and RapidIO 64-byte packets. And AS accommodates up to 256 outstanding transactions, while HyperTransport and RapidIO handle 32 outstanding transactions, said Kumar. AS also supports path-based routing for security or fail over mechanisms, as well as both credit- and status-based flow control mechanisms, he added.
Kumar said some makers 3G cellular basestations and IP-based DSL access multiplexers are already deciding to use AS. Huawei is behind the concept because, unlike its rival Cisco Systems, the China-based telecom OEM lacks a large installed base of line cards with legacy interconnects it needs to support, he added.
Agere, Intel and Vitesse will collaborate on a demo of a pre-silicon simulation of AS during the keynote address of Intel communications group CTO Eric Mentzer at the Communications Design Conference here on Tuesday when the AS spec is formally announced.
"We believe there is a market for AS, and by introducing a standard we believe that market will expand," said Kumar.