Knowledge about SNMP application entities and communities

I know that software that uses SNMP to communicate with each other on the network management workstation (Operation Management Process) and network elements to manage the network is called the SNMP application entity. SNMP defines the relationship between a management process (manager) and a management agent. This relationship is called a community ). The semantics of the description community is very complex, but its syntax is very simple.

The Simple Network Management Protocol (SNMP) is first proposed by the research team of Internet Engineering Task Force (IETF) to solve the router management problem on the Internet.

Several Application entities and SNMP are combined to form a community. Different communities are distinguished by names. The community names must comply with the hierarchical naming rules of the Internet, it is composed of non-reserved strings. In addition, an SNMP application entity can join multiple communities.

The SNMP application entity operates on the management objects in the Internet management information library. A subset of management objects that an SNMP application entity can operate on is called the snmp mib authorization range. The SNMP application entity still has further access control restrictions on access to management objects within the authorization scope, such as read-only and read/write.

In the SNMP architecture, each community is required to define its authorization scope and access methods to each object. The files that record these definitions are called "Community definition files ".

The SNMP message is always from each SNMP application entity. The message contains the name of the community where the SNMP application entity is located. In SNMP, such packets are called "packets with identity signs". The community name is used when management processes and management agents exchange and manage information packets. Management information reports include the following two parts:

(1) The community name, along with some sender's identification information (additional information), is used to verify that the sender is indeed a member of the community. The community is actually used to implement identity authentication between management SNMP application entities;

(2) data, which is the information that needs to be exchanged between two management SNMP application entities.