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Netli looks to cut 'Net delay
Service provider uses proprietary protocol that it says is faster than TCP
Network World, Tim Greene: April 21, 2003
PALO ALTO - Start-up service provider Netli promises to improve the Internet speeds of corporate Web applications without making changes to the applications and without adding software to the remote computers making Web connections.
Called NetLightning, the service reduces the delay that Internet traffic suffers when it crosses long distances.
This reduction is important with e-commerce pages in which potential customers leave a site if it takes too long to reach the resources they want. Netli says it pushes Internet delay below 1 second regardless of where Web servers and the computers accessing them are located.
Medical equipment vendor Millipore says using Netli's service reduced download times for its customers in Japan by more than 50% on average, says Jeff O'Halloran, manager of Internet services for the company. The most dramatic drop was from 7 seconds to 1.7 seconds in the time it took users in Tokyo to receive Millipore's home page, which originates in Bedford, Mass., he says.
To set up NetLightning, users redirect incoming Web-server traffic to a Netli point of presence, and the service provider takes care of the rest. For Millipore, those administrative changes took about 15 minutes, O'Halloran says. Netli sets up virtual Layer 4 trunks between the POP nearest the server and the POP nearest the requesting computer, basing the trunk on Netli's proprietary replacement for TCP called Netli Protocol.
Netli Protocol over IP uses fewer connections than TCP/IP to access the same Web data. Netli claims, for example, that the protocol can reduce from 31 to two the number of round-trip interactions needed to send a 70K byte Web page with 25 objects on it.
Netli Protocol also eliminates the slow-start feature of TCP that builds up the rate at which data is transferred gradually before reaching top speed. These and other refinements of TCP reduce the time it takes to download pages and to interact with Web applications, says Netli CEO John Peters.
While TCP/IP is still used to connect Web servers and remote computers to Netli POPs, the traffic travels a relatively small distance to reach these POPs and introduces little delay relative to the delay incurred when traffic crosses vast reaches of the Internet, Peters says. POP-to-POP tunneling improves response time so applications time-out less often.
Added benefits seen
O'Halloran says alternatives to NetLightning, such as a caching service, cost a little more but also would have required expensive changes to Millipore's Web infrastructure, and that put caching outside the budget.
Netli's service monitoring has had unexpected benefits, O'Halloran says. In one case Netli discovered an unresponsive server about 5 minutes before Millipore did, and isolated a problem with a T-1 line more quickly than Millipore could with its diagnostics, he says.
NetLightning works to improve only HTTP and Secure HTTP-S (HTTP-S) traffic and doesn't improve the downloading of streaming content. It also doesn't improve server slowdowns from traffic spikes.
Alternative services such as those from content delivery network provider Akamai address the flash-crowd problem better, says Peter Christy, co-founder of NetsEdge Research. Whereas Akamai tries to move content close to those who request it, Netli leaves the content where it is but makes it possible to reach it faster. This makes Netli more suitable for sites getting lower volumes of hits, he says.
NetLightning would be a good fit for customers that have Web applications they want their employees or business partners to reach reliably, Christy says.
Typically, the most delay is introduced between regions, so Netli has distributed 13 POPs to oversee traffic among them. Several POPs are in the U.S. where traffic is heavy. The POPs are in London, Tokyo, Shanghai, China, Singapore, Sydney, Australia, Seattle, San Francisco, Los Angeles, Chicago, Dallas, Boston, Atlanta and Washington, D.C.
These POPs are housed in collocation facilities run by Equinix and InterNAP. Peters says Netli will add more POPs as customer demand dictates.
Netli buy bit IP connections from its POPs to the Internet from multiple carriers around the world including AT&T, Singapore Telecom, NTT and Optus.
Charges for NetLightning are based on the number of applications being handled, peak number of hits they get and whether the traffic is just HTTP or whether it includes HTTP-S. Netli also charges a premium for custom reports on hits. A typical bill ranges from $10,000 to $15,000 per application per month, Netli says.
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