Smart routes

Freemarkets.com was conducting an international business-to-business auction last fall when an important bidder in Australia simply logged off because network latency had reached several minutes.

As a result of that and similar experiences, John Benzinger, vice president of IT and product development at the Internet auction service provider, implemented PathControl, an intelligent routing device from RouteScience Technologies.

The Australian customer's problem quickly went away, Benzinger says. Reports generated by PathControl showed that a congestion point on a Tier 1 backbone somewhere in Asia was causing the problem, and the RouteScience device shifted traffic to a Tier 2 provider that skirted around the traffic jam. Web page download time dropped from unavailable to around 4 seconds.

Congestion issues such as the one experienced by Freemarkets.com are a function of the limitations of Border Gateway Protocol (BGP), used by routers on the Internet to direct traffic. BGP, Benzinger says, looks for the nearest router hop, and doesn't distinguish between connection points that have a light traffic load and those where packets are waiting in the queue.

RouteScience is one of several companies introducing products and services aimed at using smart routing or intelligent routing technology to pick the best route on the fly for customers with two or more ISPs.

There's no place like multihome

The first step toward route nirvana is multihoming, or purchasing Internet connections from more than one vendor. For example, UAL Loyalty Services, a unit of United Airlines in Schaumburg, Ill., is now connecting two data centers -- a primary and a back-up -- through multihomed services provided by Internap Network Services (see story).

Igor Rafalovsky, director of networking and security for UAL, says two DS-3 links, one for each UAL data center, connect to two Internap junction points that in turn connect to multiple backbone providers. Rafalovsky says that approach provides an elegant disaster-recovery scheme while minimizing the number of router hops users around the world have to take to tap into content on the UAL servers.

Two approaches to smart routing

The next step would be to add smart routing. Rafalovsky says he's in discussions with Internap to add exactly those services, so UAL could distribute traffic between data centers based on source and destination addresses.

Intelligent routing appeals to Adam Joffe, vice president of IT for Sony Online Entertainment. He's been testing Flow Control Platform (FCP), an intelligent routing technology from netVmg, to even out the user experience of its online action game Tanarus across four Tier 1 service providers.

The number of gamers online at any given time varies widely, Joffe says. It can burst from just a few thousand during the week up to 95,000 simultaneous gamers on weekends. Joffe stresses his reason for trying the netVmg technology "is about stabilizing performance, not improving it."

He says, aside from some scaling problems, which Sony and netVmg are working on, "their software has worked as advertised and is making several thousand changes [selecting routes across multiple service providers] for us a day." Savings on bandwidth varies, but can be significant, ranging between 20% and 40%, compared with manually analyzing network performance and shifting the load between ISPs, Joffe says.

Same goal; different approaches

RouteScience's PathControl determines the best route among multiple service providers by reading latency and packet loss of a one-pixel GIF file sent out over multiple service provider links to user endpoints. The GIF generally resides on a home page or a site logon page. Every time that page is accessed, PathControl forces the GIF image to be routed across both active links, the ISP link chosen by BGP, and inactive links (ISP links ignored by BGP) to determine optimum routes.

In addition to sending out the GIF to measure performance on unknown endpoints, RouteScience's product also uses an active TCP probe to determine the best route to known endpoints -- a remote office that communicates with headquarters over a VPN, for example. The enterprise network manager specifies the known endpoints to be probed and the frequency of probing. "It would not be unreasonable to ping an enterprise's remote locations every second, so that real-time applications such as [voice over IP] can operate over constantly optimized IP-based connectivity," says RouteScience Vice President Andy Gottlieb. PathControl can cost up to $250,000.

NetVmg's FCP takes a different approach to best-path measurement. "We look at actual traffic, measuring the actual traffic to determine packet loss, latency and jitter. Then, we weed out healthy traffic from sick traffic and look for alternative paths for the sick traffic," says netVmg's Senior Vice President Eric Wolford, noting the FCP software running on a Linux box examines network flow through a mirrored port. Wolford adds that his company's technology monitors all IP-based traffic, including Sony's online gaming sessions that employ User Datagram Protocol (UDP).

The netVmg measurements from each link create a performance baseline. Network managers can then set policies for specific applications or classes of traffic, either by latency tolerance in milliseconds or by a standard deviation as a percentage from the mean of the baseline. FCP also costs up to $250,000, depending on the number of ports and bandwidth requirements.

Radware in Tel Aviv also has moved into intelligent routing with its PeerDirector product. PeerDirector, like PathControl and FCP, works with BGP routers probing a multihomed network for the best path.

Two other start-ups, Network Physics and Opnix, are working on intelligent routing technologies. Yahoo has tested Network Physics' NP-1000, which according to Mike Bennett, director of engineering for Yahoo's financial services group, shows promise in detecting choke points on the Internet and displaying the information via a graphical user interface. It uses algorithms based on chaos theory that the developers say can detect patterns in the mass of packets that make up the Internet. Bennett says the device, which costs between $25,000 and $90,000, gives network managers the information they need to manually route around the congestion points.

Network Physics says later this year the company will introduce a flow-control device that will automatically optimize net flow using the NP-1000 analytics.

Opnix's vice president of sales and marketing, Rajeev Arora, says the company's intelligent routing system consists of a $20,000 customer-premises box called the Orbit 1000 that sits next to a BGP router and sends out active probes to the multihomed ISPs to measure performance. That data is sent to a central route optimization engine managed by Opnix. Every 30 minutes, the route optimization engine updates the Orbit with best-path information. The optimization engine sells for $1,000 per month as a service, and can also be purchased for on-premises installation starting at $100,000.

Cope is a freelance writer living in Indiana. He can be reached at jc@jamescope.com.

Smart routes

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