Under control

Route control customers say they're experiencing unexpected benefits.

Route control products and services are primarily designed to pick the best paths for Internet traffic at companies that use more than one ISP. But early adopters of the technology say it delivers a range of additional benefits.

In deciding which way traffic should go, route controllers gather data that companies can also use to decide how much more bandwidth they might need to buy, to ensure that ISPs are living up to service-level agreements (SLA) and to negotiate new service provider contracts.

Route controllers are network appliances that sit behind firewalls in multihomed networks as peers to Border Gateway Protocol (BGP) routers. They probe to determine how well each available ISP connection is performing and pick the best one. Vendors of this type of equipment and service include netVmg, Proficient, Route Science Technologies and Sockeye.

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Click to see: Early Adopters

In deciding which way traffic should go, route controllers gather data that companies can also use to decide how much more bandwidth they might need to buy, to ensure that ISPs are living up to service-level agreements (SLA) and to negotiate new service provider contracts.

Route controllers are network appliances that sit behind firewalls in multihomed networks as peers to Border Gateway Protocol (BGP) routers. They probe to determine how well each available ISP connection is performing and pick the best one. Vendors of this type of equipment and service include netVmg, Proficient, Route Science Technologies and Sockeye.

Jonathan Davies, COO of hosting provider UPNetworks in San Francisco, says his Proficient equipment directs as much traffic as possible to his Williams Internet link rather than his others because it is one-third the cost. "We clearly want to use the cheap stuff whenever we can," he says, as long as performance is up to par.

BGP alone picks the route that involves the fewest router hops. But users want to factor in other parameters such as delay and which link costs the least. Route controllers do this and then update BGP route tables accordingly to determine which ISP traffic gets sent to. Later, if another ISP's performance becomes the best choice, the route controller changes the route tables again.

Widener University in Chester, Pa., uses RouteScience equipment primarily to keep performance up by preventing any one ISP link from becoming overloaded. When a certain percentage of one link is being used, the box shifts more traffic over to links that haven't reached their high-water mark, says Larry Pfeifer, Widener's network engineer. This is a core function of route control equipment, but it has value in helping users figure out how much more capacity to buy when traffic increases.

Before, if BGP was favoring one link, and it became congested over time, the school had to buy more bandwidth for that link. But it was never clear how much more bandwidth was really needed because BGP could be unpredictable, Pfeifer says. With route control, Widener now knows its traffic will be distributed across its links, so it can buy extra capacity from any of its ISPs based on how much traffic servers are generating. "Now we apportion bandwidth going out more fairly and use the full capacity we buy. It's huge," Pfeifer says.

Data gathered by route control gear in the course of performing its functions can be used to keep ISPs honest, says Scott Ellentuch, president of TTSG Internet Services in New York. The data TTSG gathers from Sockeye's route optimization service tells whether its ISPs are meeting SLAs.

TTSG also shares the data it gathers with its ISPs in hopes of encouraging them to improve their service, Ellentuch says. If the ISP sees that TTSG is diverting traffic from its link because performance is subpar, it might take steps to improve, he says. Or if it sees that traffic is being diverted because another ISP is less expensive, it might offer a better deal.