| dc.description.abstract | Message broadcasting and file delivering are major concerns of a manager to transfer strategic information and keep system consistence within an enterprise. Traditionally, message broadcast uses a push-based scheme to deliver messages from headquarters to front-line staff within a large-scaled company. However, such push-based application could cause message loss. In addition, with industry evolved in fast pace, the software functions are constantly updating, then the changes have to be reflected in all client software through a pull-based file delivery approach before new services can be launched. However, the damage for a large-scaled service company would be caused by an inconsistent system, in which client software fails to receive updated content causing loss of emergency calls and possibility of recovery.
In addition, to avoid losing contents due to the push-based method, companies could adopt pull-based algorithms to deliver contents. However, although the pull-based method can ensure that content could be received, it has a critical problem, the network is easy to be congested. The push-based method can avoid congesting the network, but it needs a specific robust design to ensure that contents could be delivered to destination.
Utilizing pull-based mechanism could resolve problems related to push-based mechanism, but consuming heavy bandwidth. Hence, adopting only a pull-based or a push-based broadcasting algorithm is no longer feasible for a large-scaled company to broadcast messages with different network bandwidth between each connected peer. Therefore, to ensure that every receiver will read downward messages thereby reducing the consumption of network bandwidth, this work proposes a robust push- and pull-based broadcasting system for sending downward messages.
A reliable pull-based content-delivering service is needed for a large-scaled service company to ensure system consistency whenever a disaster occurs. This study also proposes a file delivery mechanism and reveals its availability through analyzing its fault tolerance and failover mechanisms while errors occurred. This work proposes a reliability model of this proposed disaster avoidance mechanism. This disaster avoidance mechanism is designed for preventing damage from disasters, such as earthquakes, tsunamis, nuclear plant explosions or war.
Finally, above proposed message broadcasting mechanism and file delivering mechanism were successfully applied to a large-scaled company. The user satisfaction level of the message broadcasting system was found to be above 82.2% for the five most important factors for measuring user satisfaction. Additionally, empirical results demonstrate that the file delivering mechanism runs on 19 servers with less than 3.4 content delivery failures per million hours is better than a six-sigma capable process. | en_US |