Abstract: Firewall sandwich configurations having improved levels of system availability as well as an application-space implementation of a firewall load balancer (FLB) which provides greater operational flexibility while reducing the need for custom hardware and/or operating system software. Also disclosed is a firewall capable of functionally replacing an FLB upon detecting a failure therein.

Abstract: Firewall sandwich configurations having improved levels of system availability as well as an application-space implementation of a firewall load balancer (FLB) which provides greater operational flexibility while reducing the need for custom hardware and/or operating system software. Also disclosed is a firewall capable of functionally replacing an FLB upon detecting a failure therein.

Abstract: A computer server and method for providing assured quality-of-service request scheduling in such a manner that low priority requests are not starved in the presence of higher priority requests. Each received data request is preferably assigned a priority having both a static priority component and a dynamic priority component. The static priority component is preferably determined according to a client priority, a requested resource priority, or both. The dynamic priority component is essentially an aging mechanism so that the priority of each request grows over time until serviced. Additionally, each assigned priority is preferably determined using a scaling factor which can be used to adjust a weighting of the static priority component relative to the dynamic priority component as necessary or desired for any specific application of the invention.

Abstract: Standalone and cluster-based servers, including Web servers, control the amount of data processed concurrently by such servers to thereby control server operating performance. Each server preferably includes a dispatcher for receiving data requests from clients, and at least one back-end server for processing such requests. The dispatcher preferably maintains a persistent connection, or a set of persistent connections, with the back-end server, and forwards the data requests received from clients to the back-end server over the persistent connections. Thus, instead of maintaining a one-to-one mapping of back-end connections to front-end connections as is done in the prior art, the back-end connections can be maintained by the dispatcher and used repeatedly for sending data between the dispatcher and the back-end server. In this manner, back-end connection overhead is markedly reduced.