MX2800 STS-1 User Manual Introduction, Section 1SNMP61204659L1-1A 1-5the unit to switch to the secondary source, if available. When in External Nonrevertive timing mode, thetiming source will not switch back to the Primary External Clock in the event that it becomes available. Ifin External Revertive timing mode, the timing source will switch back to the Primary External Clock if itbecomes available. In the event that both the primary and secondary sources are lost, the unit will enterHoldover mode as described previously. Holdover mode will be exited upon recovery of at least one clocksource.3. SNMPThe embedded SNMP feature of the MX2800 STS-1 allows the unit to be accessed and controlled by anetwork manager through the 10Base-T local area network (LAN) port. The MX2800 STS-1 supports theMIB-II standard, RFC 1213, RFC 1595, and the ADTRAN Enterprise Specific MIB.NOTEMIB files are available from ADTRAN in the support section of theADTRAN Website at www.adtran.com.The term SNMP broadly refers to the message protocols used to exchange information between thenetwork management system (NMS) and the managed devices, as well as to the structure of devicemanagement databases. SNMP has three basic components:• Network manager• Agent• MIBNetwork ManagerThe network manager is a set of control programs that collect, control, and present data pertinent to theoperation of the network devices. These programs reside on a network management station.AgentThe agent is a control program that resides in every network device. This program responds to queries andcommands from the network manager, returns requested information or invokes configuration changesinitiated by the manager, and sends unsolicited traps to the manager.MIBA MIB is an industry standard presentation of all status and configuration parameters supported by anetwork device.
