CISCO-NTP-MIB

This MIB module defines a MIB which provides
        mechanisms to monitor an NTP server.
        
        The MIB is derived from the Technical Report
        #Management of the NTP with SNMP# TR No. 98-09
        authored by A.S. Sethi and Dave Mills in the
        University of Delaware.
        
        Below is a brief overview of NTP system architecture
        and implementation model. This will help understand
        the objects defined below and their relationships.
        
        NTP Intro:
        The Network Time Protocol (NTP) Version 3, is used to
        synchronize timekeeping among a set of distributed
        time servers and clients.  The service model is based
        on a returnable-time design which depends only on
        measured clock offsets, but does not require reliable
        message delivery.  The synchronization subnet uses a
        self-organizing, hierarchical master-slave
        configuration, with synchronization paths determined
        by a minimum-weight spanning tree.  While multiple
        masters (primary servers) may exist, there is no
        requirement for an election protocol.
        
        System Archiecture:
        In the NTP model a number of primary reference
        sources, synchronized by wire or radio to national
        standards, are connected to widely accessible
        resources, such as backbone gateways, and operated as
        primary time servers.  The purpose of NTP is to convey
        timekeeping information from these servers to other
        time servers via the Internet and also to cross-check
        clocks and mitigate errors due to equipment or
        propagation failures.  Some number of local-net hosts
        or gateways, acting as secondary time servers, run NTP
        with one or more of the primary servers.  In order to
        reduce the protocol overhead, the secondary servers
        distribute time via NTP to the remaining local-net
        hosts.  In the interest of reliability, selected hosts
        can be equipped with less accurate but less expensive
        radio clocks and used for backup in case of failure of
        the primary and/or secondary servers or communication
        paths between them.
        
        NTP is designed to produce three products: clock
        offset, round-trip delay and dispersion, all of which
        are relative to a selected reference clock.  Clock
        offset represents the amount to adjust the local clock
        to bring it into correspondence with the reference
        clock.  Roundtrip delay provides the capability to
        launch a message to arrive at the reference clock at a
        specified time.  Dispersion represents the maximum
        error of the local clock relative to the reference
        clock.  Since most host time servers will synchronize
        via another peer time server, there are two components
        in each of these three products, those determined by
        the peer relative to the primary reference source of
        standard time and those measured by the host relative
        to the peer.  Each of these components are maintained
        separately in the protocol in order to facilitate
        error control and management of the subnet itself.  
        They provide not only precision measurements of offset
        and delay, but also definitive maximum error bounds,
        so that the user interface can determine not only the
        time, but the quality of the time as well.
        
        Implementation Model:
        In what may be the most common client/server model a
        client sends an NTP message to one or more servers and
        processes the replies as received.  The server
        interchanges addresses and ports, overwrites certain
        fields in the message, recalculates the checksum and
        returns the message immediately.  Information included
        in the NTP message allows the client to determine the
        server time with respect to local time and adjust the
        local clock accordingly.  In addition, the message
        includes information to calculate the expected
        timekeeping accuracy and reliability, as well as
        select the best from possibly several servers.
        
        While the client/server model may suffice for use on
        local nets involving a public server and perhaps many
        workstation clients, the full generality of NTP
        requires distributed participation of a number of
        client/servers or peers arranged in a dynamically
        reconfigurable, hierarchically distributed
        configuration.  It also requires sophisticated
        algorithms for association management, data
        manipulation and local-clock control.
        
        Glossary:
        1. Host: Refers to an instantiation of the NTP
                protocol on a local processor.
        2. Peer: Refers to an instantiation of the NTP
                protocol on a remote processor connected by
                a network path from the local host.

Imported Objects

ciscoMgmtCISCO-SMI
InetAddress, InetAddressTypeINET-ADDRESS-MIB
MODULE-COMPLIANCE, OBJECT-GROUP, NOTIFICATION-GROUPSNMPv2-CONF
MODULE-IDENTITY, OBJECT-TYPE, NOTIFICATION-TYPE, Integer32, IpAddress, Gauge32, Unsigned32SNMPv2-SMI
TEXTUAL-CONVENTION, TruthValue, RowStatusSNMPv2-TC
ciscoNtpMIB .1.3.6.1.4.1.9.9.168
ciscoNtpMIBNotifs .1.3.6.1.4.1.9.9.168.0
ciscoNtpSrvStatusChange .1.3.6.1.4.1.9.9.168.0.1
ciscoNtpHighPriorityConnFailure .1.3.6.1.4.1.9.9.168.0.2
ciscoNtpHighPriorityConnRestore .1.3.6.1.4.1.9.9.168.0.3
ciscoNtpGeneralConnFailure .1.3.6.1.4.1.9.9.168.0.4
ciscoNtpGeneralConnRestore .1.3.6.1.4.1.9.9.168.0.5
ciscoNtpMIBObjects .1.3.6.1.4.1.9.9.168.1
cntpSystem .1.3.6.1.4.1.9.9.168.1.1
cntpSysLeap .1.3.6.1.4.1.9.9.168.1.1.1
cntpSysClock .1.3.6.1.4.1.9.9.168.1.1.10
cntpSysSrvStatus .1.3.6.1.4.1.9.9.168.1.1.11
cntpSysStratum .1.3.6.1.4.1.9.9.168.1.1.2
cntpSysPrecision .1.3.6.1.4.1.9.9.168.1.1.3
cntpSysRootDelay .1.3.6.1.4.1.9.9.168.1.1.4
cntpSysRootDispersion .1.3.6.1.4.1.9.9.168.1.1.5
cntpSysRefId .1.3.6.1.4.1.9.9.168.1.1.6
cntpSysRefTime .1.3.6.1.4.1.9.9.168.1.1.7
cntpSysPoll .1.3.6.1.4.1.9.9.168.1.1.8
cntpSysPeer .1.3.6.1.4.1.9.9.168.1.1.9
cntpPeers .1.3.6.1.4.1.9.9.168.1.2
cntpPeersVarTable .1.3.6.1.4.1.9.9.168.1.2.1
cntpPeersVarEntry .1.3.6.1.4.1.9.9.168.1.2.1.1
cntpPeersAssocId .1.3.6.1.4.1.9.9.168.1.2.1.1.1
cntpPeersPeerPoll .1.3.6.1.4.1.9.9.168.1.2.1.1.10
cntpPeersHostPoll .1.3.6.1.4.1.9.9.168.1.2.1.1.11
cntpPeersPrecision .1.3.6.1.4.1.9.9.168.1.2.1.1.12
cntpPeersRootDelay .1.3.6.1.4.1.9.9.168.1.2.1.1.13
cntpPeersRootDispersion .1.3.6.1.4.1.9.9.168.1.2.1.1.14
cntpPeersRefId .1.3.6.1.4.1.9.9.168.1.2.1.1.15
cntpPeersRefTime .1.3.6.1.4.1.9.9.168.1.2.1.1.16
cntpPeersOrgTime .1.3.6.1.4.1.9.9.168.1.2.1.1.17
cntpPeersReceiveTime .1.3.6.1.4.1.9.9.168.1.2.1.1.18
cntpPeersTransmitTime .1.3.6.1.4.1.9.9.168.1.2.1.1.19
cntpPeersConfigured .1.3.6.1.4.1.9.9.168.1.2.1.1.2
cntpPeersUpdateTime deprecated.1.3.6.1.4.1.9.9.168.1.2.1.1.20
cntpPeersReach .1.3.6.1.4.1.9.9.168.1.2.1.1.21
cntpPeersTimer .1.3.6.1.4.1.9.9.168.1.2.1.1.22
cntpPeersOffset .1.3.6.1.4.1.9.9.168.1.2.1.1.23
cntpPeersDelay .1.3.6.1.4.1.9.9.168.1.2.1.1.24
cntpPeersDispersion .1.3.6.1.4.1.9.9.168.1.2.1.1.25
cntpPeersFilterValidEntries .1.3.6.1.4.1.9.9.168.1.2.1.1.26
cntpPeersEntryStatus .1.3.6.1.4.1.9.9.168.1.2.1.1.27
cntpPeersUpdateTimeRev1 .1.3.6.1.4.1.9.9.168.1.2.1.1.28
cntpPeersPrefPeer .1.3.6.1.4.1.9.9.168.1.2.1.1.29
cntpPeersPeerAddress .1.3.6.1.4.1.9.9.168.1.2.1.1.3
cntpPeersPeerType .1.3.6.1.4.1.9.9.168.1.2.1.1.30
cntpPeersPeerName .1.3.6.1.4.1.9.9.168.1.2.1.1.31
cntpPeersPeerPort .1.3.6.1.4.1.9.9.168.1.2.1.1.4
cntpPeersHostAddress .1.3.6.1.4.1.9.9.168.1.2.1.1.5
cntpPeersHostPort .1.3.6.1.4.1.9.9.168.1.2.1.1.6
cntpPeersLeap .1.3.6.1.4.1.9.9.168.1.2.1.1.7
cntpPeersMode .1.3.6.1.4.1.9.9.168.1.2.1.1.8
cntpPeersStratum .1.3.6.1.4.1.9.9.168.1.2.1.1.9
cntpFilter .1.3.6.1.4.1.9.9.168.1.3
cntpFilterRegisterTable .1.3.6.1.4.1.9.9.168.1.3.2
cntpFilterRegisterEntry .1.3.6.1.4.1.9.9.168.1.3.2.1
cntpFilterIndex .1.3.6.1.4.1.9.9.168.1.3.2.1.1
cntpFilterPeersOffset .1.3.6.1.4.1.9.9.168.1.3.2.1.2
cntpFilterPeersDelay .1.3.6.1.4.1.9.9.168.1.3.2.1.3
cntpFilterPeersDispersion .1.3.6.1.4.1.9.9.168.1.3.2.1.4
ciscoNtpMIBConformance .1.3.6.1.4.1.9.9.168.2
ciscoNtpMIBCompliances .1.3.6.1.4.1.9.9.168.2.1
ciscoNtpMIBGroups .1.3.6.1.4.1.9.9.168.2.2