Abstract: With the rapid development of network technology and the increasing popularity of 5G technology,the number of devices accessing the network is increasing exponentially,the network structure is becoming increasingly complex,and malicious network attacks are frequent.How to securely and efficiently manage the large number of complex network devices is becoming a new challenge for network management.Compared with v1 and v2,SNMP v3 adds a user-based security model that provides security services such as data confidentiality,integrity,and anti-replay.However,SNMPv3 still has problems,such as the default authentication algorithm and encryption algorithm strength,which are not high,and the cryptographic algorithm does not fully support the national standard for commercial confidentiality algorithms.Based on the analysis of the existing security mechanism of SNMPv3 protocol,this paper proposes an optimization scheme for the existing problems of SNMPv3 based on user security model,embedded SM3 and SM4 national security algorithms into SNMPv3 security mechanism,and designs HMAC-SM3-192 authentication protocol and PRIV-CBC-SM4 encryption protocol for SNMP protocol based on SM3 and SM4 national security algorithms.Without significantly increasing the response time,it improves the ability to resist security threats such as forgery,information tampering and information leakage during SNMP message transmission,and achieves the optimization of SNMP protocol in terms of security.

Key words: SNMPv3, User security model, SM3 hash algorithm, SM4 symmetric encryption algorithm