Differences between SNMP ver. 2 and ver. 3

Problem:

Do I have to use snmp ver. 3 or can I get the same results from using ver. 2?

Solution:

SNMPv3 was designed to address the weak V1/V2 security. SNMPv3 is based on SNMPv2 (same packet types, it also uses SMIv2, etc.), but the main difference is that it is a lot more secure. It does not use community strings but users with passwords, and SNMPv3 packets can be authenticated and encrypted depending of how your users have been defined. In addition, the SNMPv3 framework defines user groups and MIB-views which enable an agent to control the access to its MIB objects. A MIB-view is a subset of the MIB. You can use MIB-views to define what part of the MIB a user can read (SNMP GET/GETNEXT) or write (SNMP SET), etc. The SNMPv3 framework can also be used with V1 and V2 but it was defined for SNMPv3.