ISCSI Protocol Simulation And Optimization

As data is growing explosively and becomes more and more important, traditional centralized storage system is unable to meet the storage requirements now. So new storage architectures such as storage area network (SAN) have been extensively researched and applied. Based on the ISCSI agreement, as a new network storage protocol, IP-SAN has become an important method to solve the problem. ISCSI (Internet SCSI) is a network storage specification. It integrates SCSI protocol into TCP/IP protocol and defines the mapping of SCSI between TCP/IP.In this article, it analyzed ISCSI agreement including its protocol stack model, protocol data unit format, session management, order and addressing, flow control mechanisms, re-transmission mechanism, error handling and recovery aspects. At the same time, we studied the simulation tool NS-2. Then, we implemented the ISCSI protocol using NS-2 based on the design of prototype. Through analyzing the data got from the simulation, we have done some researches on some parameters which have effects on the performance of ISCSI. The parameters involved in these tests include reading or writing, data PDU size, Maxburstlength, solicited or unsolicited data transfer, link length etc. At the same time, we presented a new interaction mechanism between the iSCSI and the TCP layer. As the iSCSI layer knows the change of network situation and changed accordingly in time, the experimental results showed that the method would improve the resource utilization and network throughput.