amount of linkage between the SLA design and the capabilities of the client side proxy as it 

was necessary to be able to capture specific parameters if they were to be specified in the 

SLA. The use of derived parameters made the SLA design a lot more flexible as it allowed 

parameters to be defined from the base parameters that the proxy captures. Again this part of 

the framework was successfully completed. 

The third and final part of the primary objective was to investigate SLA verification and 

feedback to the customer and Service Provider. This part of the primary objective was only 

partially implemented due to time restrictions. The 

SLAReporter

 class implemented a basic 

verification and feedback system for the customer, which was discussed previously in the 

case study. 

6.5.2 Future Development and System Improvements 

The work completed in this dissertation was a proof of concept. It investigated the 

possibility of capturing performance and availability information of Web delivered services 

from the end user perspective using a client side proxy. It also investigated how to specify 

SLAs for Web delivered services that could encompass the QoS requirements as perceived 

by the end user. These components became part of an overall framework that enable a 

Service Provider and the Customer to specify the performance and availability requirements 

of a service using a generic SLA. Once the SLA is defined it can be passed to a third party, 

which provides SLA verification and feedback to the Service provider and the Customer. 

These features were successfully implemented but improvements and extensions could be 

made to a number of aspects of the framework. These include: 

The issue of what information to send data back to the SLAVSP and Service Provider 

needs further investigation including what processing should be done locally by the 

proxy and what should be done remotely. 

A more flexible method is needed that the current implementation to specify the 

mappings of service functions. The basic URL matching that was implemented in the 

a

a

a