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SNMPv3MessageSyntax by vendor RFC

SNMPv3MessageSyntax file content

The SNMP protocol is used to for conveying information and commands between agents and managing entities. SNMP uses the User Datagram Protocol (UDP) as the transport protocol for passing data between managers and agents. The reasons for using UDP for SNMP are, firstly it has low overheads in comparison to TCP, which uses a 3-way hand shake for connection. Secondly, in congested networks, SNMP over TCP is a bad idea because TCP in order to maintain reliability will flood the network with retransmissions.

Management information (MIB) is represented as a collection of managed objects. These objects together form a virtual information base called MIB. An agent may implement many MIBs, but all agents must implement a particular MIB called MIB-II [16]. This standard defines variables for things such as interface statistics (interface speeds, MTU, octets sent, octets received, etc.) as well as various other things pertaining to the system itself (system location, system contact, etc.). The main goal of MIB-II is to provide general TCP/IP management information.

Use ActiveXperts Network Monitor 2019 to import vendor-specific MIB files, inclusing SNMPv3MessageSyntax.

Vendor: RFC
Mib: SNMPv3MessageSyntax  [download]
Tool: ActiveXperts Network Monitor 2019 [download]    (ships with advanced SNMP/MIB tools)
-- WinAgents MIB Extraction Wizard
-- Extracted from rfc3412.txt 16.03.2005 20:21:58


    SNMPv3Message ::= SEQUENCE {
        -- identify the layout of the SNMPv3Message
        -- this element is in same position as in SNMPv1
        -- and SNMPv2c, allowing recognition
        -- the value 3 is used for snmpv3
        msgVersion INTEGER ( 0 .. 2147483647 ),
        -- administrative parameters
        msgGlobalData HeaderData,
        -- security model-specific parameters
        -- format defined by Security Model

        msgSecurityParameters OCTET STRING,
        msgData  ScopedPduData

    HeaderData ::= SEQUENCE {
        msgID      INTEGER (0..2147483647),
        msgMaxSize INTEGER (484..2147483647),

        msgFlags   OCTET STRING (SIZE(1)),
                   --  .... ...1   authFlag
                   --  .... ..1.   privFlag
                   --  .... .1..   reportableFlag
                   --              Please observe:
                   --  .... ..00   is OK, means noAuthNoPriv
                   --  .... ..01   is OK, means authNoPriv
                   --  .... ..10   reserved, MUST NOT be used.
                   --  .... ..11   is OK, means authPriv

        msgSecurityModel INTEGER (1..2147483647)

    ScopedPduData ::= CHOICE {
        plaintext    ScopedPDU,
        encryptedPDU OCTET STRING  -- encrypted scopedPDU value

    ScopedPDU ::= SEQUENCE {
        contextEngineID  OCTET STRING,
        contextName      OCTET STRING,
        data             ANY -- e.g., PDUs as defined in [RFC3416]