Self-organization of Reconfigurable Protocol Stack for Networked Control Systems

In networked control systems （NCS）,the control performance depends on not only the control algorithm but also the communication protocol stack.The performance degradation introduced by the heterogeneous and dynamic communication environment has intensified the need for the reconfigurable protocol stack.In this paper,a novel architecture for the reconfigurable protocol stack is proposed,which is a unified specification of the protocol components and service interfaces supporting both static and dynamic reconfiguration for existing industrial communication standards.Within the architecture,a triple-level self-organization structure is designed to manage the dynamic reconfiguration procedure based on information exchanges inside and outside the protocol stack.Especially,the protocol stack can be self-adaptive to various environment and system requirements through the reconfiguration of working mode,routing and scheduling table.Finally,the study on the protocol of dynamic address management is conducted for the system of controller area network （CAN）.The results show the efficiency of our self-organizing architecture for the implementation of a reconfigurable protocol stack.

Implementation of Embedded Ethernet Based on Hardware Protocol Stack in Substation Automation System

Embedded Ethernet technology has been utilized increasingly widely as the communication mode in the substation automation system(SAS).This paper introduces the current applying situation about embedded Ethernet in SAS First.After analyzing the protocol levels used in SAS based on embedded Ethernet and the differences between the TCP and UDP,UDP/IP is selected as the communication protocol between the station-level and bay-level devices for its real-time characteristic.Then a new kind of implementation of the embedded Ethernet is presented based on hardware protocol stack.The designed scheme can be implemented easily,reduce cost significantly and shorten developing cycle.

An efficient cross-layer buffer management optimization scheme for 5G protocol stack

It is extremely challenging for the 5G User Equipment(UE)to meet the requirement of low-latency data transmission with higher achievable data rates.And user plane processing of 5G protocol stack(PS)is one of the dominating components for end-to-end data transmission in the network system.In this paper,a cross-layer buffer management scheme(CLBM)is proposed.CLBM adopts a zero-copy technique for protocol data unit(PDU)processing between protocol layers and allows to improve the memory operation efficiency significantly with reduced processing latency and CPU usage.Moreover,the PS performance profiling(PSperf)tool,a general evaluation framework for the performance measurement and analysis of PS,is implemented based on the OpenAirInterface(OAI)5G platform.The evaluation result shows that compared with the PS of OAI the CLBM strategy reduces the CPU usage of RLC,PDCP,and MAC layer processing significantly up to 20.6%,63.4%,and 38.8%,respectively.In result,the processing delay of the whole user plane of PS also has been reduced distinctly at various offered traffic load.

Research and improvement on packet capture mechanism in linux for high-speed network

With the increasing enlargement of network scale and the rapid development of network techniques, large numbers of the network applications begin to appear. Packet capture plays an important role as one basic technique used in each field of the network applications. In a high-speed network, the heavy traffic of network transmission challenges the packet capture techniques. This paper does an in-depth analysis on the traditional packet capture mechanisms in Linux, and then measures the performance bottleneck in the process of packet capture. The methods for improving the packet capture performance are presented and an optimized packet capture scheme is also designed and implemented. The test demonstrates that the new packet capture mechanism (Libpacket) can greatly improve the packet capture performance of the network application systems in a high-speed network.