At ComNet '98 this week, RND Networks, Inc. will take the wraps off a new version of its IP load-balancing servers, including one that is designed for distributed environments.
The company's Web Server Director Distributed Sites (WSD-DS) is a hardware device that allows users and service providers to balance IP traffic load between distributed server farms to ensure high availability. This enhances quality of service by transparently redirecting intranet and Internet clients to optimal server destinations when primary servers are down or busy, RND said.
For example, WSD-DS at a site in New York can redirect traffic to Paris or Los Angeles based on a user-defined traffic saturation point. Also, if the New York site is disabled, users will receive service from other locations without disruption.
WSD-DS hardware is based on an Intel Corp.-based Reduced Instruction Set Computing platform. It sports two or four Ethernet ports, or two Fast Ethernets for server and LAN attachments. WSD-DS devices also employ an RND proprietary load reporting protocol to communicate load information to one another.
Software for the WSD-DS servers allows users to define traffic thresholds by which devices redirect traffic.
These thresholds, called "user-defined weighting" by RND, can be applied to each server or server farm.
Traffic control
WSD-DS refers to these weighting thresholds during traffic redirection to ensure that no site or individual server is overloaded by user requests.
If an Internet service provider has major sites in several physical locations, each site can be configured to redirect traffic to another site in the network once the site reaches a predefined traffic threshold.
Traffic will be forwarded to this alternate site until the redirecting site traffic load drops within acceptable operating ranges.
User-defined weighting enables WSD-DS devices to provide load balancing and server/site failure detection for up to 512 logical server farms, RND said. WSD-DS also lets users retain legacy equipment and extend the life span of existing servers by relieving them of some or most of the IP traffic load.
Pricing for WSD-DS starts at $16,400 for Ethernet. The Fast Ethernet version costs $22,500.
RND: (201) 512-9771
RELATED LINKS
Review: Web server load balancers
Has links to vendor info. Network World, 9/22/97.
Web Server Director overview
From RND.
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