Symmetricom Time Server user manual Variable Definitions

Symmetricom SNMP Enterprise MIB Appendix D: SNMP – Simple Network Management Protocol

The trap message group holds the ASCII string data to send whenever an SNMP trap message is transmitted. The NTS agent sends SNMP trap messages to SNMP management hosts notifying them of some critical event at the NTS agent. The NTS issues three types of trap messages. The first type is a cold start trap message indicating when the box boots or re-initializes. The second type of trap message is issued when the NTS estimated time error has exceeded the minimum time accuracy threshold. The third trap message is issued when a packet received by the NTS agent fails SNMP authentication. The second feature notifies a network administrator immediately if the time server lost its ability to tell accurate time.

The NTP Enterprise Group furnishes information on the Network Time Protocol. This group provides packet information for the number of received, rejected, and transmitted NTP packets exchanged between the UDP transport and the NTP application layers.

Packets are rejected when they are malformed or the MD5 encryption authentication failed. In addition, time quality can be assessed by looking at the current estimated time error and comparing it with the time accuracy threshold. Finally, all of the NTP control information transmitted by the NTS in an NTP packet is available in this enterprise group. One important variable in this group is ntpSysLeap because it is the clearest indication if the NTS is telling correct time.

When GPS is used as the time synchronization source, the GPS Enterprise MIB Group provides detailed information about the satellites used by the NTS. Complete GPS satellite information exists on the number of satellites tracked and used for timing purposes, their signal strengths, the tracking mode, altitude, longitude, and latitude of the GPS antenna. This information allows you to properly set up the GPS antenna and to use the unit for time information.

When ACTS is used as the time synchronization source (see Appendix E for details), the ACTS Enterprise MIB Group provides detailed information on the ACTS dial-up modem time service. Complete information on the number and success of the ACTS phone calls as well as a detailed break down of the various possible modem and line failures that can occur. This information allows you to fine tune calling frequency with the desired time accuracy and assess the telephone line quality of the connection to the ACTS service.

Obtaining the enterprise MIB information requires you to have an SNMP management program running on your computer.

Variable Definitions

This section contains a complete and formal definition of Symmetricom’s SNMP enterprise MIB group, including all the variables in Symmetricom's Enterprise MIB, along with the MIB OID address and data types.

An electronic form of this file was included with this manual. If the disk has been misplaced or corrupted, a copy can be obtained from Symmetricom’s web site (www.truetime.net). Select Products and Literature>Reference Material to get there. The file’s name is “TrueTime.MIB”, and should compile for virtually any SNMP management software. It has been verified to work for Sun’s Solaris X-SNMP and Hewlett Packard’s OpenView management software packages.

6000-100AppD.fm Rev. D TimeVault™ User’s Manual D-111