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SNMP, SNMPv2 and SNMPv3
There are three versions of SNMP. The original version of SNMPv1 has a multi security
mechanism, which is a password. In version 1 you can not identify the sender of a mes-
sage with all certainty. This makes SNMP open, which allows the reconfiguration of
devices in the network. As a consequence of this many equipment manufacturers have
chosen not to implement all the functions in the standard. These deficiencies were
identified from the offset and a significantly improved version, SNMPv2, was planned.
This uses an encryption algorithm for authentication of transfers between the SNMP
servers and agents. SNMPv2 can also encrypt the transfer. SNMPv2, which was
intended as the follow-up was never accepted as a standard. A contributing factor was
the inability to reach agreement about how security should be implemented. However,
SNMPv2 is an important link in the development of the next version, SNMPv3.
The SNMPv3 work group was formed in March 1997 with the task to examine the
submitted security and administration proposals and from this find a common solution
to the problem. The focus of the work was, as far as possible, to complete the submit-
ted proposals and not put forward any new ideas. The proposal for SNMPv3 was
finished in 1998. This was based on version 2 as well as a security and administration
concept that centred on different modules which could be switched depending on the
level of security to be attained.
SNMPv3, the current standard, provides many more opportunities to make net-
work devices secure, yet introduction is slow. Most installed devices still follow
SNMPv1.
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