SNMP stands for Simple Network Management Protocol. It is a network protocol for monitoring and controlling network elements via a central station. It is structured as a manager/agent model and operates in a request/response format. The network manager sends requests and the network agent responds to them. Agents are software that run on the devices themselves that are being monitored.

There are three different versions of SNMP:


This is the first version of this protocol. It is very easy to set up, but also does not provide security during transmission, since the password is transmitted unencrypted.


In the second version, the agent becomes more self-sufficient. After sending an “Inform report” the agent expects a response. If the agent does not receive a response, it sends the report again. Other advantages are the encryption of the community string and the introduction of communication among managers.


The third version is the latest available. The biggest advantage is the further expansion of security features. The User-Based Security Model (USM) was introduced for message security and the View-Based Access Control Model (VACM) for access control. In addition, SNMPv3 uses an “engine ID” identifier. These IDs are required for authentication. In this process, created messages receive a special key based on the engine ID. If the correct ID is not present, the message will only contain disjointed characters thanks to the encryption.

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