Next-generation networks will usher in revolutionary changes, not just in the networking infrastructure deployed, but also in the services offered by a new generation of Network Servers. Such services will include traditional information access (over the World Wide Web) and novel emerging E-commerce applications, such as on-line computing and database services. The Network Server, in such an environment, will play a significant role in a corporate entity's presence on the Internet and especially the Web. Server responsiveness and availability will become even more important in next-generation networks than they are in today's client/server dominated network environments.
Improving either network bandwidth or server capacity, in isolation, is unlikely to satisfy all seven desired attributes of high-performance Network Servers: scalability, availability, quality of service, low-cost implementation, maintainability, accessibility and heterogeneity. A Network Server that contains all seven of these attributes is a Super Server. Given the variegated nature of these attributes, it is clear that a piece-meal approach to performance improvement, which ignores the inter-related nature of the internal network and external network capabilities on the one hand, and the server and disk (I/O) subsystem capabilities on the other is, at best, insufficient and at worst, short-sighted. The proposed solution should be ``network-centric'' in that the network operations should be optimized as much as possible, without relying solely on the availability of faster processors.
Recently, researchers have begun to consider cluster-based computers using commodity hardware as an alternative to expensive specialized hardware for building scalable Network Servers. Clustering low-cost personal computer systems is a cheap alternative to upgrading a single high-end Network Server with faster hardware. Such a solution benefits from an integrated approach aimed at achieving improved system performance and has some (but not all) of the Super Server attributes.
The objective of this project is to investigate and develop the networking technology necessary to build a Super Server. This research extends prior work on cluster-based servers by creating a network-centric server architecture, called SuperServer, that contains all seven attributes of a Super Server.
We have built two prototype Network Servers that form the foundation of the SuperServer design. The first prototype uses an OSI-Model Level-2 clustering technology called LSMAC (Load Sharing using Medium Access Control). The second prototype uses an OSI-Model Level-3 clustering technology called LSNAT (Load Sharing using Network Address Translation). Through the course of this project, we will augment the functionality of the prototypes until they meet the requirements of a Super Server.
The expected contributions of this research are summarized as follows: