Tools make dumb bandwidth smart
Intelligent routing can monitor the network, balance speed and cost, and choose the best route
- By William Jackson
- Sep 13, 2002
ATLANTA'Network administrators need to work smarter'not just harder'at managing bandwidth, speakers said last week at the Networld+Interop and Comdex trade show.
'In the late 1990s, folks threw bandwidth at every problem,' said Madeline Chan, vice president of strategic marketing for Proficient Networks Inc. of San Francisco. Also, carrier bankruptcies and a surge of interest in continuity of operations have led organizations to acquire multiple connections to the Internet.
That means there's a lot of dumb bandwidth that does not necessarily deliver data any faster. Proficient Networks and other vendors are promoting so-called intelligent routing, either by a customer premises appliance or as a network service.
Intelligent routing chooses the best network route depending on user criteria. It monitors network performance, then balances speed and cost based on billing structures and customer traffic patterns.
If economy is paramount, it chooses routes that avoid data bursts, which incur a higher billing rate. If avoiding latency is tops, it routes traffic over the fastest path.
Representatives of Sockeye Networks Inc. of Waltham, Mass., said their routing service can improve performance over existing connections by two to 10 times, saving the cost of adding more bandwidth.
Intelligent routing sounds like quality of service, but it isn't, Chan said. Quality of service typically is guaranteed at the application layer, whereas Proficient's box, which sits on the customer's network, works at the lower link layer.
'We can't really deliver against service-level agreements,' Chan said, because available links might not be good enough. What intelligent routing does is provide 'the best quality, given what's available,' she said.
Multihoming'the use of multiple connections to public networks through multiple providers'has spurred the growth of intelligent routing.
Although the number of multihomed enterprises, by some estimates, has risen by 50 percent a year since 1996, Sockeye vice president Brendan Hannigan said his scan of the Internet turned up only 8,500 systems with multiple connections.
Chan said only about 20 percent of the top 2,000 global companies are multihomed.
Proficient Networks, Sockeye and their competitors are banking that the percentage will continue to grow.
'Ultimately, I think the carrier crisis has made this a must-have,' Chan said.
Circuits have not been disappearing as carriers declare bankruptcy, but customer service suffers, they said.
Although government is an attractive market for intelligent routing vendors, it is not setting the pace in adoption.Go with shortcuts
Governments 'are highly interested,' Chan said. 'But I think they are a little leery of the cutting edge.'
Multihoming requires use of the Border Gateway Protocol to set up connections between networks. BGP detects shortest paths to set up routing tables, even if shortest is not always best.
'BGP is absolutely necessary, but it doesn't solve all the problems,' Hannigan said. 'It cannot react to actual traffic conditions.' Nor does it avoid congested routes or understand billing structures that might make a longer route preferable.
The Proficient Network Policy Engine appliance talks with the router on a customer's network. The 0510A model has a 10/100-Mbps Ethernet port and can support up to six peering sessions. It starts at $35,000.
The larger 1010A model starts at $50,000 with more licensing costs depending on network needs. It has a Gigabit Ethernet port and supports up to 30 peering sessions.
The Policy Engine can help configure BGP and set static policy requirements for handling some types of traffic. It can also route traffic based on jitter, packet loss or latency, and it can balance loads between connections based on either cost or percentage of traffic. It periodically tests and re-engineers network connections.
Sockeye's GlobalRoute service uses a server-based agent on the customer network to monitor local conditions. It also gathers data from 13,000 servers on more than 1,000 networks around the world through Akamai Technologies Inc. of Cambridge, Mass.
From that global view of backbone conditions, it makes routing decisions according to customer-defined policy. The service is priced on a monthly basis.
William Jackson is freelance writer and the author of the CyberEye blog.