Research On Communication Protocol Of The Intelligent Network Disk Storage System

Because Internet technology drive the development of computer technology, the need of data storage have been extraordinary changed. These require the storage system have tremendous capability, quickly and effectively access the data and effectively manage data. On the one hand, to meet the increasingly massive data storage and backup needs of enterprises and institutions, the number of storage devices has been more and more investment; On the other hand, many domestic and foreign well-known research institutions and large enterprises have attached greater importance to the research of storage technology. Network storage technology in recent years has become the hotspot of computer storage technology research.First, the paper introduces the architectonic, advantages and disadvantages of DAS, NAS and SAN. DAS is restricted by server and has extensibility. Aiming to solve the problem in network storage system, this paper proposes the framework of intelligent network disk storage system. This framework has good performance, scalability and reliability. And it is intelligent and cost little to build and manage.The main content of this paper is on the IND storage system communication design and implementation. To overcome the deficiency of the poor performance of network storage system caused by multi-copy and context switch in TCP/IP, this paper introduces a light weight transport protocol .The achieved major research results include the following aspects.1. This paper proposes the framework of intelligent network disk storage system. This framework has intelligent, good performance, little cost, high scalability and high reliability.2. This paper introduces the Research and Implementation of a LAN-based lightweight data transfer protocol --High-performance Disk Storage Protocol (HDSP).The HDSP protocol Includes the following features:(1) Streamlining the protocol level: As to avoid high load caused by the complex TCP / IP protocol to the IND storage system services, HDSP protocol bypassing the TCP / IP protocol, communicate to data link layer directly.(2) Using efficient transmission control mechanism: the characteristics of a reliable link for the LAN design a NACK-based transmission control mechanism, to avoid TCP / IP protocol communication process generated a large number of ACK signals occupy both communication bandwidth and CPU processing cycles.(3) Optimize the data access path: In order to transfer data from card to hard disk, TCP / IP protocol requires three times memory copy and 2 times context switching. We designed a one-time-copy data path mechanism, making HDSP protocol data packets transferred from network card to hard disk requires only 1 CPU memory copy ,without any context switch.3. We Implement the HDSP protocol based on the Linux system and Realtek8169C network card, provides a class of SAN block-level data access methods for the client of the IND storage systems.Finally, this paper experiment the performance of the HDSP protocol. The results showed that: compared to NFS protocol (based on TCP / IP protocol), HDSP protocol allows the server's throughput increased by 18%, the system load (CPU utilization) decreased by 23%.