Silicon Access Launches Billing Chip
The iFlow Accountant is the industry's first dedicated billing and policing co-processor, the company claims. It's designed to give carriers the ability to bill for services on a per-flow, per-service, and per-packet basis, and that's something they are crying out for, according to Anthony Gallo, director of product marketing for Silicon Access.
Right now, carriers are stuck in the trap of supplying commodity IP services, which have little added value other than getting the data from destination to source, he says. Carriers can only compete in this market by slashing their prices, and with many of them in financial difficulties, they don't want to do that.
The answer is to supply multiple services with different service-level agreements (see The Service-Aware Switch). But, as Gallo points out, manufacturers of routers and switches have had their work cut out, keeping up with the escalating line rates and aggregate capacities of the Internet, and have had limited resources to throw at the problem of service differentiation.
What's more, in Gallo's view, many vendors of merchant silicon such as Applied Micro Circuits Corp. (AMCC) (Nasdaq: AMCC) seem to have tumbled into the same trap. The majority are concentrating on offering a single-chip solution for packet processing, where the focus is on transport. They can do higher level processing, but only at the expense of speed, and in any case, the statistics and policing functions are restricted, he contends.
Enter the Accountant. It performs three main functions: classification, enforcement, and billing. "No matter how many flows, you need to classify them all, to determine what sort of data they're carrying," explains Gallo. "Then you need to enforce the service, to make sure the customer gets what he paid for and no more. And last, you need to keep track of all the statistics, to ensure the bill is accurate."
Gallo claims that the Accountant can handle policing operations on 128,000 flows at any one time. This is good, but does not put it at the top of the class in terms of number of flows. Some traffic managers also do policing, Vitesse Semiconductor Corp.'s (Nasdaq: VTSS) being one of them. Its traffic manager chip, PaceMaker 2.5 can support 256,000 flows (see Vitesse Offers PaceMaker, TeraStream).
However, Gallo contends that the Accountant is the only chip to offer policing of thousands of flows in conjunction with statistics for billing. It can maintain up to 1 million counters for billing purposes, he claims.
From a billing perspective, the chip also contains several nifty features to ensure the accuracy of the data. Gallo claims that the Accountant is unique, even among custom ASICs, in having a "snapshot" mode, which freezes a counter and redirects new requests to another counter. This freezes information so it can be downloaded to the billing system, preventing customers from being double billed.
Another point worth noting is that at 10 Gbit/s the rollover rate of a 42-bit counter is 1 hour, meaning that there is plenty of time in which to request an information update before the counter gets overwritten. (The chip also contains 21-bit counters, which are more appropriate for keeping track of lower-speed flows.)
To do all this requires an extremely sophisticated chip, Gallo notes. To wit, it's built in state-of-the-art 0.13 micron process technology, and contains 24 Mb of on-board SRAM (the state-of-the-art in SRAM is 18 Mb on a single chip, he says).
The iFlow Accountant is the third chip Silicon Access has released. In August 2001, it launched -- and is now shipping -- the iFlow Address Processor, which provides an address lookup function similar to a CAM (content addressable memory). And in October 2001, it announced the iFlow Packet Processor, a programmable network processing unit that is expected to begin sampling later this quarter (see Silicon Access Processes Packets). The Accountant is already shipping, the company claims. It costs about $300.
Silicon Access is planning to launch two further chips in its portfolio: a classifier, which is currently at the fab, and a traffic manager, which is scheduled for the second half of 2002. All five chips in the portfolio are designed to work together, but that doesn't exclude them from working separately. "We have design wins for all these chips individually," says Gallo.
Indeed, with internal ASIC teams representing the most significant source of competition to off-the-shelf network processors, it makes sense for Silicon Access to offer a piecewise solution rather than a single-chip one, Gallo claims. "When we go to a customer, we ask 'What's your problem?' and we sell them a solution to that, rather than offering a fork-lift upgrade."
Silicon Access has raised $85 million in funding to date from a group of top-drawer investors, including Comdisco, Intel Capital, Morgan Stanley Dean Witter & Co., Norwest Venture Partners, Raza Foundries, and Tallwood Venture Capital.
— Pauline Rigby, Senior Editor, Light Reading