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disk. Implementation on an 8 node cluster showed that PRESS can improve the server

throughput by about 29% compared to the TCP/IP model. These studies support the

idea that a cluster based Web server is one of the most effective architectures, in terms

of both performance and cost.

However, many choices in designing and building cluster based Web servers re 

main to be explored. In addition, considering the complex features of cluster based Web

servers, a myriad of issues require investigation in regards to Web performance and ser 

vice quality. For example, little research has been done on the performance impact of the

Secure Socket Layer (SSL) [72] on cluster based Web servers or aggressive adopting of

new architectural trends such as the large amount of available memory on programmable

NICs to increase system throughput.

Therefore, the main motivation of this research is to design and analyze various

issues regarding cluster based Web servers. This research includes the following: i)

design of coscheduled Web servers, which exploit various coscheduling techniques to

minimize the latency time of the client requests, ii) design of a load balancing scheme

for the SSL connections between clients and application servers, and iii) investigation

of the NIC data caching scheme, which exploits the available large memory space in an

intelligent/programmable Network Interface Card (NIC) to enhance performance.