Research Of Auto-extension Cache System Based On Active Network

With the rapid development of Internet, the increasing Internet consumer and the delay of service network lead to a serial of issues, such as web service load and consumer accessing delay, and the service quality could be not guaranteed. Cache technology can solve this problem, and it is widely applied. However, the deployment and expansion of traditional network cache system need artificial preparation, and communication cooperation results in a great mount of load. Active network can download the cache service code and form cache service node automatically and expand and deploy them easily. Therefore, it is significant to research the self-expansion network cache system of network. This dissertation mainly consists of following aspects:Firstly, theory of active network technology is reviewed. The architecture of active network system and active nodes of kernel components are mainly analyzed, integrated and divergent project are simply introduced. The application of active network cache mechanism is summarized. And the advantage of active network is concluded.Secondly, theory of current network cache technology is discussed. System architecture of current popular network cache system is analyzed. For the communication mechanism, ICP and Cache Digest protocols are studied, the advantages and the disadvantages of two protocols and current algorithms are summarized. And current cache system's problems are concluded.Thirdly, automatic expanding cache system based on the active network mechanism is proposed for the advantage of active network in cache and the problem of current cache system. It is illustrated from its designing idea and systematic network topological structure. Active nodes in active network become cache serving node by cache code automatically downloaded and deployed, and distributed cache system is formed by adding them into the cache system through automatic expanding cache system and by the correspondence of RCD. Systematic frame mainly includes the monitor, communication cooperation device, file converter, and load balancer. Monitor completes its self-expansion by monitoring active nodes'entry or withdrawing from the cache system in network. Communication cooperation device mainly completes the communication cooperation of cache code. Load balancing device mainly complete load balance between nodes. Later, one correspondence process of this cache system used by the consumer is given. In addition, the system is theoretically evaluated from the time delay and cache hit ratio.Finally, evaluation standard adopted in general cache system is introduced. By network simulator, trace-driven stimulation method was applied, and stimulation experiments were conducted by the way of trace-driven simulation. The results of the stimulation experiments show that comparing with hierarchy configuration cache system active network cache system in this dissertation has the advantages in cache hit ratio and respond time delay.