Anagran Promises TLC for TCP

It's not Caspian. That's one of the main things Lawrence Roberts wants everyone to know about his new company, Anagran Inc.

But there's plenty more that Roberts, founder of now-defunct IP equipment vendor Caspian Networks, is keen to say about Anagran, which today unveils its maiden product, the FR-1000 Intelligent Flow Router.

The FR-1000, says Roberts, is an edge router that can control traffic more efficiently than deep packet inspection (DPI) products, allowing TCP networks to run at 95 percent of capacity instead of the usual 30 percent. It's a 1U box with 48 Gbit/s of capacity (not double-counting inputs and outputs), and has its roots in the Flow-Based Networking that was also the basis of Caspian Networks's router.

But Roberts left Caspian more than three years ago, convinced the company wouldn't fly. And he was right; Caspian folded last year. (See Caspian Closes Its Doors.)

Roberts is known for a lot more than Caspian. He's part of that elite group that helped build the Internet in the first place. (See Dr. Lawrence Roberts.) And, with Robertsian flair, he's willing to proclaim that Anagran could "shift the Internet to a fundamentally new technology."

But he's worried that people will dismiss Anagran as a Caspian clone.

"Caspian came at a time when it looked like it should be a core box," Roberts says. "Their margin was too low, even though the product worked and everybody was happy with it. I had quit halfway through because I saw the margins would be zip, and I thought there were a lot of other things we could do with the technology."

Compared with Caspian's costs, Anagran comes cheap. The company first came to light in 2004 as Roberts collected his early funding. Three years later, investors have put just $28 million into the 75-employee company. Caspian's third round alone was worth three times that. (See Supercomm Snippets: The Sequel, Anagran Raises $8M, and Anagran Attracts $12M.)

Roberts was able to keep development costs low by relying on off-the-shelf chips, something startups couldn't necessarily do circa 1999. The heart of the FR-1000 is an FPGA programmed with Anagran's algorithms, alongside what Roberts describes as an inexpensive routing chip. All told, the box lists for $70,000.

Anagran isn't just an exercise in pinching pennies, though. Roberts says he's spent the last few years expanding on what he started with Caspian, coming up with a more powerful way to use flow-based networking.

So, what is the FR-1000?

Inside the box
Anagran's router was conceived as an add-on to live networks, something that would be deployed as an aggregation box at the network edge.

Like Caspian, Anagran uses flow-based routing, where the router processes traffic in terms of flows and not just by individual packets. But this time, Anagran adds the wrinkle of being able to control the bandwidth used by each flow.

The goal is to avoid the high packet loss that comes when the network gets overloaded. Put differently, Anagran claims to turn TCP into a better juggler, letting the network maintain high throughput on a higher number of flows.

When a normal router reaches overcapacity, it starts discarding packets, often in a round-robin fashion, sometimes affecting traffic flows that aren't contributing to the problem. "The result is, everybody slows down at once. Then, they all start speeding up at once," Roberts says. To avoid this oscillatory behavior and the congestion that comes with it, carriers run their routers at around 30 percent of capacity, to leave enough headroom for surges in traffic, according to Roberts.

To Page 2

The FR-1000 is pickier. It watches each flow and, depending on its behavior and the bandwidth available, assigns it a maximum rate. Video gets a higher rate than voice, for instance. Then, if a particular flow approaches the assigned maximum, the router drops one packet from that flow, slowing it down without affecting any others.

The end result is that the router can handle surges in traffic more gracefully, which in turn suggests operators can safely run the network at higher capacity. "It's the first time you've been able to get every flow exactly the rate you want," Roberts says.

One possible application would be in the data center, where the flow router could be the last aggregation box pointing to the outside world. It could tell video servers that a particular stream doesn't have the available bandwidth for video, so the server could notify the user rather than deliver a substandard stream.

'Cheap as mud'
This idea, called intelligent flow discard, has been kicked around for decades, Roberts says, but it was too expensive to be practical, in part because of the amount of memory it required. Now that DRAM is "cheap as mud," as Roberts puts it, Anagran was able to give it a shot.

Others can, too, although Roberts thinks he's got a substantial headstart. "I don't think people can do it that fast, because it was seven years work on my part between Caspian and here. I don't think anybody could do it in less than three years after they decide to do it -- and that [decision] could be another year."

Roberts claims ISPs are asking for Anagran's kind of functionality even though it hasn't existed yet. And it does appear operators are looking for ways to better control traffic. Juniper Networks Inc. (NYSE: JNPR), for instance, is pitching the use of policy management for building more services-aware networks. (See Juniper Pushes Services Policy.)

Anagran's more direct competitors appear to be the DPI vendors, including Allot Ltd. (Nasdaq: ALLT), Ellacoya Networks Inc. , and Sandvine Inc. . But the philosophies are different. DPI relies on peeking into packet payloads, while Anagran ignores that level of detail in favor of managing the flows to which the packets belong.

Because it's so different, Anagran will have to prove its benefits are worth using instead of more familiar equipment, says David Vorhaus, an analyst with Yankee Group Research Inc.

"Service providers don't have experience with this kind of thing, and you're talking about fixing something that's not necessarily broken," Vorhaus says. "To layer on a DPI solution and a policy management solution to major networks is not prohibitively expensive."

Even so, Vorhaus says Anagran's onto something novel. "I'm going to be interested, along with everybody else, to see the reaction."

Speaking of reaction, what does Cisco Systems Inc. (Nasdaq: CSCO) think of all this? It's mostly Cisco routers, after all, that hit the capacity crunch Anagran claims to fix, and Cisco owns some DPI technology through its acquisition of P-Cube. (See Cisco Plucks P-Cube for $200M.)

Cisco didn't immediately return a call for comment, but Roberts says he doesn't expect to see Cisco develop a technology akin to Anagran's. "They'll never do this, because it'll drop their revenues 10 to 1," he says.

— Craig Matsumoto, West Coast Editor, Light Reading