Summary of SNMP Configuration Tasks

This section compares SNMP versions in terms of their support for features and usage scenarios to help you select the appropriate SNMP version for your network.

The device supports SNMPv1, SNMPv2c, and SNMPv3. Table 1 lists the features supported by SNMP, and Table 2 lists the SNMP versions supported by each feature. Table 3 describes the usage scenarios of SNMP versions, helping you choose the appropriate version for the communication between an NMS and managed devices according to the operation conditions of your network.

When a device is managed by multiple NMSs running different SNMP versions, configure SNMPv1, SNMPv2c, and SNMPv3 on the device so that it can communicate with all the NMSs.

**Table 1** Description of features supported by SNMP
Feature	Description
Access control	This function restricts a user's device administration rights. It gives specific users the rights to manage specified objects on devices, providing fine-grained management.
Authentication and privacy	Authentication and privacy packets are transmitted between the NMS and managed devices. This prevents data packets from being intercepted or modified, improving data sending security.
Error code	Error codes help the administrator to identify and rectify faults. More varied error codes make it easier for the administrator to manage the device.
Trap	Traps are sent from managed devices to the NMS. Traps help administrators to find device faults. The managed devices do not require the acknowledgement from the NMS after sending traps.
Inform	Informs are sent from managed devices to the NMS. The managed devices require the acknowledgement from the NMS after sending informs.
GetBulk	GetBulk allows an administrator to perform GetNext operations in batches. In a large network, GetBulk reduces the workload of administrators and improves management efficiency.

After a restart, an NMS can receive the informs that are sent by managed devices during the restart.

**Table 2** SNMP versions supported by each feature
Feature	SNMPv1	SNMPv2c	SNMPv3
Access control	Access control based on the community name and MIB view	Access control based on the community name and MIB view	Access control based on the user, user group, and MIB view
Authentication and privacy	Authentication based on the community name	Authentication based on the community name	Supported authentication and encryption modes are as follows: Authentication mode: MD5 SHA Encryption mode: DES56 AES128 AES192 AES256 3DES
Error code	6 error codes supported	16 error codes supported	16 error codes supported
Trap	Supported	Supported	Supported
Inform	Not supported	Supported	Supported
GetBulk	Not supported	Supported	Supported

**Table 3** Usage scenarios of different SNMP versions
Version	Usage Scenario
SNMPv1	Small networks with simple networking and low security requirements or small networks with good security and stability, such as campus networks and small enterprise networks.
SNMPv2c	Medium and large networks with low security requirements or with good security (for example, VPNs) but on which there are many services running, leading to traffic congestion. Configure the managed devices to send SNMP notifications as informs to ensure that the NMS can receive them.
SNMPv3	Networks of various scales, in particular, networks that have strict security requirements and can be managed only by authorized network administrators. For example, SNMPv3 can be used if data between the NMS and managed device needs to be transmitted over a public network.

If you plan to build a network, choose an SNMP version according to your usage scenario. If you plan to expand or upgrade an existing network, run the same SNMP version on the managed devices as that running on the NMS to ensure that they can communicate.