Products: Global Load Balancing
Copyright © 2004 Open Enterprise Systems, Co., Ltd.
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April 16, 2004
This document will discuss a technique, which Open Enterprise Systems (OES) has developed, to optimize geographically-distributed web servers. This technique fulfills two usage requirements:
Speed. Web visitors should be directed to the closest [1] available server for high-speed, low-latency service.
Availability. If a server experiences a problem (for example, software failure, hacker defacement, or upstream network disconnection), all further requests for service will be routed to the other servers.
The most effective path to meet these criteria is using DNS name resolution to dynamically return the IP address of the most appropriate server.
[1] For this discussion, the term close means close in the networking sense, i.e. the fewest hops along the lowest-latency route. For example, for servers based in Hong Kong and San Francisco, a user in eastern Russia is geographically nearer to Hong Kong. However, since Russia has more high-quality connections with the U.S., she should be directed to the U.S. for better performance.