Lance Russell

Modular TCP Handoff Design in STREAMS-Based TCP/IP Implementation

Content-aware request distribution is a technique which takes into account the content of the request when distributing the requests in a web server cluster. A handoff protocol and TCP handoff mechanism were introduced to support content-aware request distribution in a client-transparent manner. Content-aware request distribution mechanisms enable the intelligent routing inside the cluster to provide the quality of service requirements for different types of content and to improve overall cluster performance.We propose a new modular TCP handoff design based on STREAMSbased TCP/IP implementation in HP-UX 11.0. We design the handoff functions as dynamically loadable modules. No changes are made to the existing TCP/IP code. The proposed plug-in module approach has the following advantages: flexibility-TCP handoff functions may be loaded and unloaded dynamically, without node function interruption; modularity- proposed design and implementation may be ported to other OSes with minimal effort.

Customized library of modules for STREAMS-based TCP/IP implementation to support content-aware request processing for Web applications

Content-aware request processing enables the intelligent routing and request processing inside a cluster to provide the QoS (quality of service) requirements for different types of content and to improve the overall cluster performance. A STREAMS-based TCP/IP implementation in HP-UX 11.0 provides a convenient framework to design a library of new STREAMS modules to support content-aware request distribution and differentiation inside a cluster. The proposed modules take into account the specifics of different cluster architectures and workload characteristics. These modules are designed as dynamically loadable modules, and no changes are made to the existing TCP/IP code. The proposed design has the following advantages: flexibility (new modules may be loaded and unloaded dynamically, without node function interruption) and modularity (the proposed modules may be ported to other operating systems with minimal effort; more importantly, the proposed STREAMS modules can be easily integrated and deployed into commercial operating systems, so that end-users may take advantage of these solutions much sooner).