Foundry Networks this week added global server load-balancing and DNS redirection capabilities to its ServerIronGT E-series of Layer 4-7 appliances.
The upgrade allows a ServerIronGT appliance to balance Web traffic across the Internet to servers spread out across multiple sites. Server health monitoring, traffic congestion sensing and DNS attack prevention are also features included in the upgrade.
The ServerIronGT appliance, introduced in June, is a multipurpose traffic management box aimed at large data centers and Web farms. The device would be deployed in front of servers inside a data center; it adds Layer 4 load balancing and Layer 7 application switching, as well as other specialized traffic management features such as spam filtering and denial-of-service attack protection. The update adds Foundry's TrafficWorks Global Server Load Balancing (GSLB) software to ServerIronGT, letting ServerIronGT reroute traffic to Web servers at other sites if traffic congestion, server processor overload or other factors affect Web site availability.
The software uses standards-based IP routing and DNS protocols for traffic redirection. It also allows a ServerIronGT appliance to protect Web servers from DNS-based attacks, where attackers try to overload a server with DNS queries. The ServerIronGT box can now rate limit DNS requests made on servers to prevent such attacks.
The ServerIronGT appliances are based on network processor technology, rather than Foundry's homegrown Layer 4-7 ASICs, which are used in Foundry's ServerIron switches. The network processor-based systems are more adaptable for adding new features and applications, while the ASIC-based switches are built more for raw performance, Foundry says.
The ServerIronGT comes in four flavors: dual- and four-port Gigabit Ethernet versions for midsize enterprises, as well as a 16-port Gigabit and dual-port 10G Ethernet models for very large data centers or service provider networks.
The GSLB software upgrade for the ServerIronGT costs US$4,000. The ServerIronGT hardware ranges from US$16,000 to US$45,000.