Snmpv3 Support; Snmp's View Of A Network - NEC Express5800/ftServer Administrator's Manual

SNMP Foundations and Concepts

SNMPv3 Support

SNMPv3 support includes implementation of IETF RFCs 3410 through 3418. The third
version of the Simple Network Management Protocol, presented by the IETF as the
Internet Standard Management Framework RFC3410, SNMPv3 incorporates elements
of SNMPv1 and SNMPv2, and shares the same basic modular architecture. This
framework consists of four structures: a data definition language (SMIv1), a
management information base (MIB) defining management information, a separately
defined communication protocol, and security and administration applications and
engines.
Features of SNMP version 1, SNMP version 2, and SNMP version 3 are not mutually
exclusive. IETF Best Current Practices 74 (BCP74) describes how to implement these
protocols compatibly on networks and on internetworked environments so that objects
can be managed using the least sophisticated protocol required. In this way, networked
and internetworked objects may be managed using SNMPv1, for example, without
becoming obsoleted if the network is commingled into a larger network where objects
are managed using SNMPv2 or SNMPv3.
This is necessary because the SNMP schema treats all networks as potentially a single
network, providing for addressing every object uniquely with a single MIB. Accordingly,
implementing conformant extensions to SNMP should not cause interoperability
conflicts with existing standards-conforming SNMP implementations. In the SNMP
network universe, any number of SNMP servers can exist, and they can manage the
objects they know about using SNMPv1, SNMPv2, SNMPv3, and with confidence that
any SNMPv4 or subsequent protocol that may be defined will not obsolete existing
SNMP servers and their managed objects.

SNMP's View of a Network

SNMPv1 defines a simple and robust internet protocol-based communications method
for tracking the status of and managing almost any network-interactive item that is
sufficiently defined as an object in a MIB.
SNMP normally uses UDP protocol implemented on socket-based IP communications,
but may also be implemented using TCP/IP and another IP-based protocol, and also
on non-IP protocols such as RS-232 serial communications by spoofing an IP-based
communication or by piggybacking it on another transmission or transfer protocol.
SNMP can also take advantage of common security enhancements implemented over
IP, such as the Secure Socket Layer and other encryption, authentication, and remote
access technologies provided by, for example, ssh, the Openssh package.
SNMPv2 expands management capabilities of SNMPv1 by providing a mechanism for
more easily defining the managed objects that SNMP communicates with. SNMP
refines SNMPv2 definitions and adds important security features. Net-SNMP supports
SNMPv1, SNMPv2, and SNMPv3 protocols. Because of the simple basic structure of
8-14 Express5800/ftServer: System Administrator's Guide for the Linux Operating System