Difference Between SNMPv2 and SNMPv3

SNMPv2 vs SNMPv3

Internet Protocol (IP) networks use managing devices such as Simple Network Management Protocol (SNMP) to monitor network attached devices. In a computer network, a group of devices are attached, and they are managed and monitored by a manager. An agent, which is a software module in a managed device, reports information through the SNMP to the manager which has a Network Management System (NMS) that executes the applications that monitor and control managed devices.
There are seven SNMP protocol data units (PDU):

GetRequest – request to retrieve the value of a variable from the manager to the agent.
SetRequest – request to change the value of a variable from the manager to the agent.
GetNextRequest – request to find variables from the manager to the agent.
GetBulkRequest – enhanced version of GetNextRequest.
Response – reply from the agent to the manager through the return of variables.
Trap – simultaneous message from the agent to the manager.
InformRequest – simultaneous messages between managers.




There are three versions of SNMP:

1. SNMPv1, which is the network management protocol being used by the Internet.
2. SNMPv2, which is a revised version of the SNMPv1. It contains improvements in performance, confidentiality, security, and communications between managers. Its party-based security system is very complex, though, and has to be revised in order to be able to use it with the SNMPv1.
3. SNMPv3, which has added cryptographic security and new concepts, terminology, remote configuration enhancements, and textual conventions. Its new security features are:

 
It provides confidentiality through the encryption of packets to block intruders from the outside. It assures message integrity by protecting packets with a protection mechanism. It ensures that the message is from a reliable source.

The Request for Comments (RFC), a memorandum that describes methods, research, and changes that are applied to the Internet has given SNMPv3 full Internet standard and regards older versions as outmoded. SNMPv2 agents can be used as proxy agents for SNMPv1 managed devices. It has improved error handling and SET commands over that of SNMPv1. Its Inform features allows acknowledgement of the receipt of messages by the manager. SNMPv3, on the other hand, has a better security system. It ensures that the messages are read only by the designated recipient, and any messages that are intercepted by unauthorized users are garbled especially if they are forwarded through the Internet.



Summary:

1.Simple Network Management Protocol version 2 (SNMPv2) is a managing device used to monitor devices in a computer network while the Simple Network Management Protocol version 3 (SNMPv3) is the latest version of the SNMP.
2.SNMPv2 has a complex party-based security system while the SNMPv3 has a cryptographic security system.
3.SNMPv2 agents can be used as proxy agents for SNMPv1 managed devices.
4.SNMPv2 introduced the Inform features which allow acknowledgement of the receipt of messages by the manager while the SNMPv3 introduced an enhanced security system that authenticates messages and ensures their privacy especially if they are forwarded through the Internet.