SNMP-COMMUNITY-MIB

All MIBs › SNMP-COMMUNITY-MIB

Organization: SNMPv3 Working Group

Last Updated: 2003-08-06

Category: SNMP Framework

Description: Defines objects for mapping between community strings and version-independent SNMP message parameters, with source address validation on incoming requests.

IPNetwork Monitor uses several OIDs from this MIB in network discovery and polling the applicable devices. Start monitoring SNMP-COMMUNITY-MIB with a free 30-day trial of IPNetwork Monitor.

What Is SNMP-COMMUNITY-MIB?

SNMP-COMMUNITY-MIB is an IETF standards MIB (RFC 3584) that defines objects for mapping SNMPv1/SNMPv2c community strings to version-independent SNMPv3 security parameters, enabling coexistence of SNMPv1, SNMPv2c, and SNMPv3 on the same agent. Categories exposed are security/access-configuration data — community-to-security-name mappings, context engine/name bindings, transport tags, and source-address validation for incoming community-based requests. It is a configuration/security-state MIB rather than a hardware/performance MIB — an operator uses it to confirm which communities are configured, their storage type (permanent vs. volatile), and row status (active/notInService), effectively auditing SNMP access-control configuration and management-plane software health rather than physical device status. It explicitly exists to bridge SNMPv1/v2c with the SNMPv3 USM/VACM security framework and is commonly deployed alongside SNMP-TARGET-MIB via its snmpTargetAddrExtTable extension. It is deployed on any SNMP agent — router, switch, server, or other managed device — that needs to support SNMPv1/v2c community-based access alongside SNMPv3. The SNMP-COMMUNITY-MIB RFC (RFC 3584) is cited directly in the module itself, underscoring its role as the standards-track bridge between legacy community-based access and SNMPv3 security.

IPNetwork Monitor allows you to monitor SNMP objects defined in SNMP-COMMUNITY-MIB. Use the built-in SNMP Monitoring Browser to explore available variables, view their current values and descriptions, and select the objects you want to monitor. You can then create SNMP monitors, configure thresholds, and receive alerts when monitored values change.

Supported Devices

vendor-neutral, standards-based MIB, not tied to a specific manufacturer
any SNMP-managed network device, server, or agent

Monitoring Examples

An admin would walk snmpCommunityTable to audit each snmpCommunityEntry's snmpCommunityName against its snmpCommunitySecurityName, snmpCommunityContextEngineID, and snmpCommunityContextName, confirming community strings map to the intended security identity. snmpCommunityStorageType and snmpCommunityStatus reveal whether a given community row is a permanent configuration entry or a volatile one that could disappear on reboot, and whether it is currently active. The snmpTargetAddrExtTable extension adds source-address tagging so an operator can verify a community is restricted to expected source addresses, flagging a misconfiguration if an unexpected source is accepted; an unexpected active row in snmpCommunityTable could reveal an unauthorized or forgotten legacy SNMPv1/v2c community still granting access.

What Can Be Monitored

community string to security name mapping
SNMP community row status
SNMP community storage type (permanent/volatile)
context engine/context name bindings
source-address restriction for community access

Imported Objects

From SNMP-FRAMEWORK-MIB

SnmpAdminString
SnmpEngineID

From SNMP-TARGET-MIB

SnmpTagValue
snmpTargetAddrEntry	OBJECT-TYPE

From SNMPv2-CONF

MODULE-COMPLIANCE
OBJECT-GROUP

From SNMPv2-SMI

Integer32
IpAddress
MODULE-IDENTITY
OBJECT-TYPE
snmpModules

From SNMPv2-TC

RowStatus
StorageType

OIDs

OID symbolic	OID numeric	Type	Access	Description
SNM snmpCommunityContextEngineID	1.3.6.1.6.3.18.1.1.1.4	SnmpEngineID	read-create	The contextEngineID indicating the location of the context in which management information is accessed when using the community string specified by the corresponding instance of snmpCommunityName. The default value is the snmpEngineID of the entity in which this object is instantiated.
STR snmpCommunityContextName	1.3.6.1.6.3.18.1.1.1.5	SnmpAdminString	read-create	The context in which management information is accessed when using the community string specified by the corresponding instance of snmpCommunityName.
snmpCommunityEntry	1.3.6.1.6.3.18.1.1.1		not-accessible	Information about a particular community string.
STR snmpCommunityIndex	1.3.6.1.6.3.18.1.1.1.1	SnmpAdminString	not-accessible	The unique index value of a row in this table.
snmpCommunityMIB	1.3.6.1.6.3.18			This MIB module defines objects to help support coexistence between SNMPv1, SNMPv2c, and SNMPv3. Copyright (C) The Internet Society (2003) This version of this MIB module is part of RFC 3584; see the RFC itself for full legal notices.
snmpCommunityMIBCompliance	1.3.6.1.6.3.18.2.1.1			The compliance statement for SNMP engines which implement the SNMP-COMMUNITY-MIB.
snmpCommunityMIBCompliances	1.3.6.1.6.3.18.2.1
snmpCommunityMIBConformance	1.3.6.1.6.3.18.2
snmpCommunityMIBFullCompliance	1.3.6.1.6.3.18.2.1.3			The compliance statement for SNMP engines which implement the SNMP-COMMUNITY-MIB with full read-create access.
snmpCommunityMIBGroups	1.3.6.1.6.3.18.2.2
snmpCommunityMIBObjects	1.3.6.1.6.3.18.1
OCT snmpCommunityName	1.3.6.1.6.3.18.1.1.1.2	OCTET STRING	read-create	The community string for which a row in this table represents a configuration. There is no SIZE constraint specified for this object because RFC 1157 does not impose any explicit limitation on the length of community strings (their size is constrained indirectly by the SNMP message size).
STR snmpCommunitySecurityName	1.3.6.1.6.3.18.1.1.1.3	SnmpAdminString	read-create	A human readable string representing the corresponding value of snmpCommunityName in a Security Model independent format.
ROW snmpCommunityStatus	1.3.6.1.6.3.18.1.1.1.8	RowStatus	read-create	The status of this conceptual row in the snmpCommunityTable. An entry in this table is not qualified for activation until instances of all corresponding columns have been initialized, either through default values, or through Set operations. The snmpCommunityName and snmpCommunitySecurityName objects must be explicitly set. There is no restriction on setting columns in this table when the value of snmpCommunityStatus is active(1).
STO snmpCommunityStorageType	1.3.6.1.6.3.18.1.1.1.7	StorageType	read-create	The storage type for this conceptual row in the snmpCommunityTable. Conceptual rows having the value 'permanent' need not allow write-access to any columnar object in the row.
snmpCommunityTable	1.3.6.1.6.3.18.1.1		not-accessible	The table of community strings configured in the SNMP engine's Local Configuration Datastore (LCD).
snmpCommunityTableGroup	1.3.6.1.6.3.18.2.2.1			A collection of objects providing for configuration of community strings for SNMPv1 (and SNMPv2c) usage.
SNM snmpCommunityTransportTag	1.3.6.1.6.3.18.1.1.1.6	SnmpTagValue	read-create	This object specifies a set of transport endpoints which are used in two ways: - to specify the transport endpoints from which an SNMP entity will accept management requests, and - to specify the transport endpoints to which a notification may be sent using the community string matching the corresponding instance of snmpCommunityName. In either case, if the value of this object has zero-length, transport endpoints are not checked when either authenticating messages containing this community string, nor when generating notifications. The transports identified by this object are specified in the snmpTargetAddrTable. Entries in that table whose snmpTargetAddrTagList contains this tag value are identified. If a management request containing a community string that matches the corresponding instance of snmpCommunityName is received on a transport endpoint other than the transport endpoints identified by this object the request is deemed unauthentic. When a notification is to be sent using an entry in this table, if the destination transport endpoint of the notification does not match one of the transport endpoints selected by this object, the notification is not sent.
snmpProxyTrapForwardCompliance	1.3.6.1.6.3.18.2.1.2			The compliance statement for SNMP engines which contain a proxy forwarding application which is capable of forwarding SNMPv1 traps using SNMPv2c or SNMPv3.
snmpProxyTrapForwardGroup	1.3.6.1.6.3.18.2.2.3			Objects which are used by proxy forwarding applications when translating traps between SNMP versions. These are used to preserve SNMPv1-specific information when translating to SNMPv2c or SNMPv3.
snmpTargetAddrExtEntry	1.3.6.1.6.3.18.1.2.1		not-accessible	Information about a particular mask and mms value.
snmpTargetAddrExtTable	1.3.6.1.6.3.18.1.2		not-accessible	The table of mask and maximum message size (mms) values associated with the snmpTargetAddrTable. The snmpTargetAddrExtTable augments the snmpTargetAddrTable with a transport address mask value and a maximum message size value. The transport address mask allows entries in the snmpTargetAddrTable to define a set of addresses instead of just a single address. The maximum message size value allows the maximum message size of another SNMP entity to be configured for use in SNMPv1 (and SNMPv2c) transactions, where the message format does not specify a maximum message size.
I32 snmpTargetAddrMMS	1.3.6.1.6.3.18.1.2.1.2	Integer32	read-create	The maximum message size value associated with an entry in the snmpTargetAddrTable. Note that a value of 0 means that the maximum message size is unknown.
OCT snmpTargetAddrTMask	1.3.6.1.6.3.18.1.2.1.1	OCTET STRING	read-create	The mask value associated with an entry in the snmpTargetAddrTable. The value of this object must have the same length as the corresponding instance of snmpTargetAddrTAddress, or must have length 0. An attempt to set it to any other value will result in an inconsistentValue error. The value of this object allows an entry in the snmpTargetAddrTable to specify multiple addresses. The mask value is used to select which bits of a transport address must match bits of the corresponding instance of snmpTargetAddrTAddress, in order for the transport address to match a particular entry in the snmpTargetAddrTable. Bits which are 1 in the mask value indicate bits in the transport address which must match bits in the snmpTargetAddrTAddress value. Bits which are 0 in the mask indicate bits in the transport address which need not match. If the length of the mask is 0, the mask should be treated as if all its bits were 1 and its length were equal to the length of the corresponding value of snmpTargetAddrTable. This object may not be modified while the value of the corresponding instance of snmpTargetAddrRowStatus is active(1). An attempt to set this object in this case will result in an inconsistentValue error.
IP snmpTrapAddress	1.3.6.1.6.3.18.1.3	IpAddress	accessible-for-notify	The value of the agent-addr field of a Trap PDU which is forwarded by a proxy forwarder application using an SNMP version other than SNMPv1. The value of this object SHOULD contain the value of the agent-addr field from the original Trap PDU as generated by an SNMPv1 agent.
OCT snmpTrapCommunity	1.3.6.1.6.3.18.1.4	OCTET STRING	accessible-for-notify	The value of the community string field of an SNMPv1 message containing a Trap PDU which is forwarded by a a proxy forwarder application using an SNMP version other than SNMPv1. The value of this object SHOULD contain the value of the community string field from the original SNMPv1 message containing a Trap PDU as generated by an SNMPv1 agent. There is no SIZE constraint specified for this object because RFC 1157 does not impose any explicit limitation on the length of community strings (their size is constrained indirectly by the SNMP message size).

RFC description

Defines SNMP community-based security model for SNMPv1/v2c authentication and access control (RFC 3584).

Start monitoring vendor-neutral, standards-based MIB, any SNMP-managed network device, server, or agent (community-to-security mapping) with a free 30-day trial of IPNetwork Monitor. Import MIBs, browse SNMP OIDs, create custom SNMP monitors, configure alerts, and monitor any SNMP-enabled network device from a single console.

Download SNMP-COMMUNITY-MIB

What Is SNMP-COMMUNITY-MIB?

Supported Devices

Monitoring Examples

What Can Be Monitored

This MIB depends on

Related MIBs

RFC description