Designed And Implemented Of Standard Token Of STS And Virtual Token Of DLMS/COSEM

Nowadays,with the continuous development of communication network,the intelligent meter reading system based on DLMS/COSEM protocol has been gradually developed and improved,while the original STS standard selling electricity is outdated and inconvenient because the transmission medium adopts the original Token paper printing and IC card storage.Now STS association is drafting relevant draft,hoping to integrate STS into DLMS/COSEM protocol,so that STS can further reach.This paper is a practice based on this demand.In this paper,IEC62055-41 standard,IEC62055-42 draft,IEC62056-DLMS/COSEM series standards are studied in depth.Based on the DLMS/COSEM protocol,the planning and implementation of STS related data are carried out,so that STS standard can be combined with DLMS/COSEM standard.Firstly,the paper designs and implements the STS standard parsing,including extracting Token Class and Encrypted data,STA07 algorithm decrypting,extracting the subtype and valid data of Token,top up Token parsing,key modification Token parsing,clearing credit Token parsing,etc.,and uses the testing software of STS association’ s STSSimulator.exe to implement Token parsing is verified.Secondly,IEC62056-61 object identification and IEC62056-62 interface class used in Token are established,DLMS/COSEM is designed and implemented as a virtual Token carrier,and DLMS/COSEM security communication and STS related data management part are designed,and DLMS/COSEM protocol communication test,management test and the most important Token credit recharge test are carried out by upper computer software,which is confirmed the correctness and generality of the design and implementation of this paper,as well as the feasibility of using DLMS/COSEM as virtual token transmission for prepaid smart table.Thirdly,the paper focuses on the security of selling electricity,overlays the encryption of STS and the security of DLMS/COSEM,completes the access control and data transmission security of STS data in DLMS/COSEM protocol,and makes the selling electricity designed and implemented in this paper get the double security protection of STS protocol layer and DLMS/COSEM protocol layer.In the whole design process,the computer technology such as C language,IAR compiling environment and so on are mainly used,and the second development freedom of the chip supplier is fully utilized.On the basis of fully considering the STS-DLMS/COSEM function realization,the price problem when being sold as a commodity is considered as much as possible,so that the realization of this paper as a real product can achieve a good popularity.Of course,there are still many problems to be explored,such as how to recharge the electricity meter through direct remote communication with the master station,whether to consider introducing asymmetric ECC algorithm in DLMS/COSEM protocol layer for bidirectional authentication and sensitive data authentication,and how to reasonably run asymmetric algorithm in embedded system.