Guest

Cisco ONS 15454 Series Multiservice Transport Platforms

Timing Reference

  • Viewing Options

  • PDF (1.3 MB)
  • Feedback

Introduction

This document provides information about Cisco ONS 15454 users and node timing.


Note


Unless otherwise specified, “ONS 15454” refers to both ANSI and ETSI shelf assemblies.

Note


With references provided to configuration guides, see:

  • For software releases 9.3 to 9.8, the Cisco ONS 15454 DWDM Configuration Guide
  • For software release 10.0 and later, an appropriate guide from one of these three:
    • Cisco ONS 15454 DWDM Control Card and Node Configuration Guide
    • Cisco ONS 15454 DWDM Line Card Configuration Guide
    • Cisco ONS 15454 DWDM Network Configuration Guide

The document contains the topics mentioned below.

Node Timing Parameters

SONET timing parameters must be set for each Cisco ONS 15454 shelf. Each ONS 15454 independently accepts its timing reference from one of three sources:

  • The building integrated timing supply (BITS) pins on the ONS 15454 backplane (ANSI) or MIC-C/T/P coaxial connectors (ETSI).
  • An OC-N/STM-N card installed in the ONS 15454. The card is connected to a node that receives timing through a BITS source.
  • The internal ST3 clock on the control card.

You can set ONS 15454 timing to one of three modes: external, line, or mixed. If timing is received from a BITS source, set ONS 15454 timing to external. If timing is received from an OC-N/STM-N card, set the timing to line. The BITS connection on Cisco ONS 15454 M6 shelf is through the external connection unit (ECU) and is through the power module on Cisco ONS 15454 M2 shelf.

In typical ONS 15454 networks:

  • One node is set to external. The external node derives its timing from a BITS source wired to the BITS backplane pins. The BITS source, in turn, derives its timing from a primary reference source (PRS) such as a Stratum 1 clock or global positioning satellite (GPS) signal.
  • The other nodes are set to line. The line nodes derive timing from the externally timed node through the OC-N/STM-N trunk (span) cards. The DWDM node normally derives timing from the line using the OSCM or OSC-CSM card that are inside an OC-3/STM-1 channel.

You can set three timing references for each ONS 15454 . The first two references are typically two BITS-level sources, or two line-level sources optically connected to a node with a BITS source. The third reference is usually assigned to the internal clock provided on every ONS 15454 control cards. However, if you assign all three references to other timing sources, the internal clock is always available as a backup timing reference. The internal clock is a Stratum 3 (ST3), so if an ONS 15454 node becomes isolated, timing is maintained at the ST3 level.

The CTC Maintenance > Timing > Report tab show current timing information for an ONS 15454 , including the timing mode, clock state and status, switch type, and reference data.


Caution


Mixed timing allows you to select both external and line timing sources. However, Cisco does not recommend its use because it can create timing loops. Use this mode with caution.

The OC3 port of the TNC/TNCE/TSC/TSCE card can be set as the timing reference. In the ONS 15454 M2 shelf, BITS-2 is not supported.

Network Timing

The following figure shows an ONS 15454 network timing setup example. Node 1 is set to external timing. Two timing references are set to BITS. These are Stratum 1 timing sources wired to the BITS input pins on the Node 1 backplane. The third reference is set to internal clock. The BITS output pins on the backplane of Node 3 are used to provide timing to outside equipment, such as a digital access line access multiplexer.

In the example, Slots 5 and 6 contain the trunk (span) cards. Timing at Nodes 2, 3, and 4 is set to line, and the timing references are set to the trunk cards based on distance from the BITS source. Reference 1 is set to the trunk card closest to the BITS source. At Node 2, Reference 1 is set to Slot 5 because it is connected to Node 1. At Node 4, Reference 1 is set to Slot 6 because it is connected to Node 1. At Node 3, Reference 1 could be either trunk card because they are at an equal distance from Node 1.

Synchronization Status Messaging

Synchronization status messaging (SSM) is a SDH and SONET protocol that communicates information about the quality of the timing source. SSM messages are carried on the S1 byte of the SONET Line layer or on S1 byte of the SDH section overhead. They enable SONET or SDH devices to automatically select the highest quality timing reference and to avoid timing loops.

SSM messages are either Generation 1 or Generation 2. Generation 1 is the first and most widely deployed SSM message set. Generation 2 is a newer version. If you enable SSM for the ONS 15454 or the ONS 15454 SDH , consult your timing reference documentation to determine which message set to use.

The following table shows the SDH message set.

Table 1 SDH SSM Message Set

Message

Quality

Description

G811

1

Primary reference clock

STU

2

Sync traceability unknown

G812T

3

Transit node clock traceable

G812L

4

Local node clock traceable

SETS

5

Synchronous equipment

DUS

6

Do not use for timing synchronization

The following two tables show the Generation 1 and Generation 2 message sets for SONET.

Table 2 SSM Generation 1 Message Set

Message

Quality

Description

PRS

1

Primary reference source—Stratum 1

STU

2

Synchronization traceability unknown

ST2

3

Stratum 2

ST3

4

Stratum 3

SMC

5

SONET minimum clock

ST4

6

Stratum 4

DUS

7

Do not use for timing synchronization

RES

Reserved; quality level set by user

Table 3 SSM Generation 2 Message Set

Message

Quality

Description

PRS

1

Primary reference source—Stratum 1

STU

2

Synchronization traceability unknown

ST2

3

Stratum 2

TNC

4

Transit node clock

ST3E

5

Stratum 3 E

ST3

6

Stratum 3

SMC

7

SONET minimum clock

ST4

8

Stratum 4

DUS

9

Do not use for timing synchronization

RES

Reserved; quality level set by user

Procedures for ONS 15454 Timing

This section contains the procedure related to ONS 15454 timing.

NTP-G53 Set Up Timing

Purpose

This procedure provisions Cisco ONS 15454 timing.

Tools/Equipment

None

Prerequisite Procedures

"NTP-G51 Verify DWDM Node Turn Up" procedure in "Turn Up a Network" chapter of the Cisco ONS 15454 DWDM Network Configuration Guide

"DLP-G46 Log into CTC" task in Connect the PC and Log into the GUI document.

Required/As Needed

Required

Onsite/Remote

Onsite or remote

Security Level

Provisioning or higher

Procedure
    Step 1   Complete the DLP-G95 Set Up External or Line Timing task if an external building integrated timing supply (BITS) source is available. This is the most common ONS 15454 timing setup method.
    Step 2   If an external BITS source is not available, complete the DLP-G96 Set Up Internal Timing , on page 9 task. This task can provide only Stratum 3 timing.
    Step 3   Repeat this procedure at each node in the network.

    DLP-G95 Set Up External or Line Timing

    Purpose

    This task defines the ONS 15454 timing source (external or line).

    Tools/Equipment

    None

    Prerequisite Procedures

    "DLP-G46 Log into CTC" task in Connect the PC and Log into the GUI document.

    Required/As Needed

    Required

    Onsite/Remote

    Onsite or remote

    Security Level

    Provisioning or higher

    Procedure
      Step 1   In node view (single-node mode) or shelf view (multishelf mode), click the Provisioning > Timing > General tabs.
      Step 2   In the General Timing area, complete the following information:
      • Timing Mode-Choose External if the ONS 15454 derives its timing from a BITS source wired to the backplane pins (ANSI) or a MIC-C/T/P front-mount electrical connection (FMEC) (ETSI); choose Line if timing is derived from an OSC-CSM or OSCM card that is optically connected to the timing node. A third option, Mixed, allows you to set both external and line timing references. Because Mixed timing might cause timing loops, we do not recommend its use. Use this mode with care.
        Note   

        In ONS 15454 M6 the BITS is connected to ECU or ECU2 BITS Connectors. Refer to "DLP-G296 Install Timing Wires on ONS 15454 M6 - ANSI" in the Cisco ONS 15454 Hardware Installation Guide . In ONS 15454 M2 he BITS is connected to BITS connectors on the Power Unit.

      • SSM Message Set-Choose the Generation 2 synchronization status messaging (SSM) option. See the section Synchronization Status Messaging for more information about SSM, including definitions of the SONET timing levels.
        Note   

        Generation 1 is used only by SONET or SDH ONS 15454 nodes that are connected to equipment that does not support Generation 2.

      • Quality of RES-Sets the timing quality for the user-defined, reserved (RES) S1 byte if your timing sources supports RES. Most timing sources do not use RES. If it does not support RES, choose RES=DUS (do not use for timing reference). Qualities are displayed in descending quality order as ranges. For example, in Generation 1 SSM, ST3<RES<ST2 means that the timing reference RES is higher than a Stratum 3 (ST3) and lower than a Stratum 2 (ST2)
      • Revertive-Select this check box if you want the ONS 15454 to revert to a primary reference source after the conditions that caused it to switch to a secondary timing reference are corrected.
      • Reversion Time-If Revertive is checked, choose the amount of time that the ONS 15454 will wait before reverting to its primary timing source. Five minutes is the default.
      Step 3   In the Reference Lists area, complete the following information:
      Note   

      You can define up to three timing references for the node and up to six BITS Out references. BITS Out references define the timing references used by equipment that can be attached to the node's BITS Out pins on the backplane (ANSI) or the MIC-C/T/P FMEC (ETSI). If you attach equipment to BITS Out pins, you normally attach it to a node with Line mode, because equipment near the external timing reference can be directly wired to the reference.

      • NE Reference-Allows you to define three timing references (Ref 1, Ref 2, Ref 3). The node uses Reference 1 unless a failure occurs to that reference, in which case the node uses Reference 2. If Reference 2 fails, the node uses Reference 3, which is typically set to Internal Clock. Reference 3 is the Stratum 3 clock provided on the control card. The options that appear depend on the Timing Mode setting.
        • If the Timing Mode is set to External, your options are BITS-1, BITS-2, and Internal Clock.
        • If the Timing Mode is set to Line, your options are the node's working OSCM cards, OSC-CSM cards, transponder (TXP) cards, muxponder (MXP) cards, and Internal Clock. Choose the cards or ports that are directly or indirectly connected to the node wired to the BITS source. Set Reference 1 to the card that is closest to the BITS source. For example, if Slot 5 is connected to the node wired to the BITS source, choose Slot 5 as Reference 1.
        • If the Timing Mode is set to Mixed, both BITS references and the OSCM, OSC-CSM, TXP, or MXP cards are available, allowing you to set a mixture of external BITS clocks and OSCM, OSC-CSM, TXP, or MXP cards as timing references.
      • BITS-1 Out/BITS-2 Out-Sets the timing references for equipment wired to the BITS Out backplane (ANSI) or MIC-C/T/P FMEC (ETSI) pins. BITS-1 Out and BITS-2 Out are enabled when BITS-1 Out and BITS-2 Out facilities are put in service. If Timing Mode is set to external, choose the OSCM, OSC-CSM, TXP, or MXP card used to set the timing. If Timing Mode is set to Line, you can choose an OSCM, OSC-CSM, TXP, or MXP card or choose NE Reference to have the BITS-1 Out, BITS-2 Out, or both, follow the same timing references as the network element (NE).
        Note   

        All TXP or MXP card client ports are available for timing regardless of the card's termination mode. TXP or MXP trunk ports can be a timing reference when ITU-T G.709 is set to OFF and the Termination Mode is set to LINE. You cannot choose TXP_MR_2.5G and OTU2_XP card client ports as a timing reference.

        Note   

        The system prevents BITS In and BITS Out timing to be set on the same node.

      Step 4   Click Apply .
      Step 5   Click the BITS Facilities tab.
      Note   

      The BITS Facilities section sets the parameters for your BITS-1 and BITS-2 timing references. Many of these settings are determined by the timing source manufacturer. If equipment is timed through BITS Out, you can set timing parameters to meet the requirements of the equipment.

      Step 6   In the BITS In area, complete the following information:
      • Facility Type-(TCC2P/TNC/TNCE/TSC/TSCE only) Choose the BITS signal type supported by your BITS clock, either DS1 or 64KHz+8KHz.
      • BITS In State-If Timing Mode is set to External or Mixed, set the BITS In state for BITS-1, BITS-2, or both, to IS (in service) depending on whether one or both BITS input pin pairs are connected to the external timing source. If Timing Mode is set to Line, set the BITS In state to OOS (out of service).
      Step 7   If the BITS In state is set to OOS, continue with Step 8. If the BITS In state is set to IS, complete the following information:
      • Coding-Choose the coding used by your BITS reference, either B8ZS (binary 8-zero substitution) or AMI (alternate mark inversion).
      • Framing-Choose the framing used by your BITS reference, either ESF (Extended Super Frame) or SF (D4) (Super Frame).
      • Sync Messaging-Check this check box to enable SSM. SSM is not available if Framing is set to Super Frame.
      • Admin SSM-If the Sync Messaging check box is not checked, you can choose the SSM Generation 2 type from the drop-down list. Choices are PRS (Primary reference source; Stratum 1), ST2 (Stratum 2), TNC (Transit Node Clock), ST3E (Stratum 3E), ST3 (Stratum 3), SMC (SONET minimum clock), and ST4 (Stratum 4).
      Step 8   In the BITS Out area, complete the following information, as needed:
      • Facility Type-(TCC2P/TNC/TNCE/TSC/TSCE only) Choose the BITS Out signal type, either DS1 or 64KHz+8KHz for ANSI and E1, 2Mhz, or 64Khz for ETSI.
      • BITS Out state-If equipment is connected to the node's BITS output pins on the backplane (ANSI) or MIC-C/T/P FMEC (ETSI) and you want to time the equipment from a node reference, set the BITS Out state for BITS-1, BITS-2, or both, to IS , depending on which BITS Out pins are used for the external equipment. If equipment is not attached to the BITS output pins, set the BITS Out state to OOS .
      Step 9   If the BITS Out state is set to OOS, continue with Step 10. If the BITS Out state is set to IS, complete the following information:
      • Coding-Choose the coding used by your BITS reference, either B8ZS, AMI, or HDB3.
      • Framing-Choose the framing used by your BITS reference, either ESF, SF (D4), or FAS+CAS+CRC.
      • AIS Threshold-If SSM is disabled or Super Frame is used, choose the quality level where a node sends an alarm indication signal (AIS) from the BITS 1 Out and BITS 2 Out backplane pins (ANSI) or MIC-C/T/P FMEC (ETSI). An AIS alarm is raised when the optical source for the BITS reference falls to or below the SSM quality level defined in this field.
      • LBO-If an external device is connected to the BITS Out pins, set the line build-out (LBO) distance between the ONS 15454 and an external device. If an external device is connected to BITS Out, choose the distance between the device and the ONS 15454 . Options are: 0-133 ft (default), 134-266 ft, 267-399 ft, 400-533 ft, and 534-655 ft. Line build out (LBO) relates to the BITS cable length. If an external device is not connected to BITS Out, leave this field set to the default.
      Step 10   Click Apply.
      Note   

      Refer to Cisco ONS 15454 DWDM Troubleshooting Guide for timing-related alarms.

      Step 11   Return to your originating procedure (NTP).

      DLP-G96 Set Up Internal Timing

      Purpose

      This task sets up internal timing (Stratum 3) for an ONS 15454 .

      Tools/Equipment

      None

      Prerequisite Procedures

      "DLP-G46 Log into CTC" task in Connect the PC and Log into the GUI document.

      Required/As Needed

      As needed (use only if a BITS source is not available)

      Onsite/Remote

      Onsite or remote

      Security Level

      Provisioning or higher


      Caution


      Internal timing is Stratum 3 and is not intended for permanent use. All ONS 15454 SONET (ANSI) or SDH (ETSI) nodes should be timed to a Stratum 2 (or better) primary reference source. Internal timing is appropriate for DWDM nodes.


      Procedure
        Step 1   In node view (single-node mode) or shelf view (multishelf mode), click the Provisioning > Timing > General tabs.
        Step 2   In the General Timing area, complete the following information:
        • Timing Mode-Choose External
        • SSM Message Set-Set to Generation 1.
        • Quality of RES-Does not apply to internal timing.
        • Revertive-Does not apply to internal timing.
        • Reversion Time-Does not apply to internal timing.
        Step 3   In the Reference Lists area, enter the following information:
        • NE Reference
          • Ref 1-Set to Internal Clock.
          • Ref 2-Set to Internal Clock .
          • Ref 3-Set to Internal Clock .
        • BITS-1 Out/BITS-2 Out-Set to None.
        Step 4   Click Apply .
        Step 5   Click the BITS Facilities tab.
        Step 6   In the BITS Facilities area, change the BITS In state and BITS Out state to OOS for BITS 1 and BITS 2. Disregard the other BITS Facilities settings; they are not relevant to internal timing.
        Step 7   Click Apply.
        Step 8   Return to your originating procedure (NTP).

        NTP-G87 Change Node Timing Parameters

        Purpose

        This procedure changes the timing parameters for the ONS 15454 . To switch the timing reference, see the NTP-G112 Change the Node Timing Reference procedure.

        Tools/Equipment

        None

        Prerequisite Procedures

        NTP-G53 Set Up Timing

        "DLP-G46 Log into CTC" task in Connect the PC and Log into the GUI document.

        Required/As Needed

        As needed

        Onsite/Remote

        Onsite or remote

        Security Level

        Provisioning or higher


        Caution


        The following procedure might be service affecting and should be performed during a scheduled maintenance window.


        Procedure
          Step 1   Complete the "NTP-G103 Back Up the Database" procedure in the chapter, "Maintaining the Node" of the Cisco ONS 15454 DWDM Network Configuration Guide .
          Step 2   Click the Provisioning > Timing > General tabs.
          Step 3   In the General Timing section, change any of the following information:
          • Timing Mode
            Note   

            Because mixed timing can cause timing loops, Cisco does not recommend using the Mixed Timing option. Use this mode with care. Because mixed timing can cause timing loops, Cisco does not recommend using the Mixed Timing option. Use this mode with care.

          • SSM Message Set
          • Quality of RES
          • Revertive
          • Revertive Time

          See the NTP-G53 Set Up Timing task for field descriptions.

          Step 4   In the Reference Lists area, you can change the following information:
          Note   

          Reference lists define up to three timing references for the node and up to six BITS Out references. BITS Out references define the timing references used by equipment that can be attached to the node's BITS Out pins on the backplane. If you attach equipment to BITS Out pins, you normally attach it to a node with Line mode because equipment near the external timing reference can be directly wired to the reference.

          • NE Reference
          • BITS 1 Out
          • BITS 2 Out
          Step 5   In node view (single-shelf mode) or shelf view (multishelf mode), click the Provisioning > Timing > BITS Facilities tabs.
          Step 6   In the BITS In section, you can change the following information:
          Note   

          The BITS Facilities section sets the parameters for your BITS1 and BITS2 timing references. Many of these settings are determined by the timing source manufacturer. If equipment is timed through BITS Out, you can set timing parameters to meet the requirements of the equipment.

          • BITS In State
          • Coding
          • State
          • Framing
          • Sync Messaging
          • Admin SSM
          Step 7   In the BITS Out section, you can change the following information:
          • Coding
          • Framing
          • AIS Threshold
          • LBO
          Step 8   Click Apply. Confirm that the changes appear.
          Caution   

          Internal timing is Stratum 3 and is not intended for permanent use. All ONS 15454s should be timed to a Stratum 2 or better primary reference source.

          Step 9   Complete the "NTP-G103 Back Up the Database" procedure in the chapter, "Maintaining the Node" of the Cisco ONS 15454 DWDM Network Configuration Guide .

          Stop. You have completed this procedure.

          NTP-G112 Change the Node Timing Reference

          Purpose

          This procedure enables automatic timing reference switching or returns the node timing to normal operation.

          Tools/Equipment

          None

          Prerequisite Procedures

          "DLP-G46 Log into CTC" task in Connect the PC and Log into the GUI document.

          Required/As Needed

          As needed

          Onsite/Remote

          Onsite or remote

          Security Level

          Maintenance or higher

          Procedure
            Step 1   Complete the DLP-G259 Manual or Force Switch the Node Timing Reference task as needed.
            Step 2   Complete the DLP-G260 Clear a Manual or Force Switch on a Node Timing Reference task as needed.

            Stop. You have completed this procedure.

            DLP-G259 Manual or Force Switch the Node Timing Reference

            Purpose

            This task commands the node to switch to the timing reference you have selected.

            Tools/Equipment

            None

            Prerequisite Procedures

            "DLP-G46 Log into CTC" task in Connect the PC and Log into the GUI document.

            Required/As Needed

            As needed

            Onsite/Remote

            Onsite or remote

            Security Level

            Maintenance or higher

            Procedure
              Step 1   In node view (single-shelf mode) or shelf view (multishelf mode), click the Maintenance > Timing > Source tabs.
              Step 2   From the Reference drop-down list for the desired Clock, choose the desired reference.
              Step 3   From the Operation drop-down list for the desired Clock, choose one of the following options:
              • Manual -This operation commands the node to switch to the reference you have selected if the synchronization status message (SSM) quality of the reference is not lower than the current timing reference.
              • Force-This operation commands the node to switch to the reference you have selected, regardless of the SSM quality (if the reference is valid).
                Note   

                For information about the Clear option, see the DLP-G260 Clear a Manual or Force Switch on a Node Timing Reference task.

              Step 4   Click Apply next to the timing source.
              Step 5   Click Yes in the confirmation dialog box. If the selected timing reference is an acceptable valid reference, the node switches to the selected timing reference. If the selected timing reference is invalid, a warning dialog box appears. Click OK; the node will not switch to the new timing reference.
              Step 6   Return to your originating procedure (NTP).

              DLP-G260 Clear a Manual or Force Switch on a Node Timing Reference

              Purpose

              This task clears a Manual or Force switch on a node timing reference and reverts the timing reference to its provisioned reference.

              Tools/Equipment

              None

              Prerequisite Procedures

              "DLP-G46 Log into CTC" task in Connect the PC and Log into the GUI document.

              Required/As Needed

              As needed

              Onsite/Remote

              Onsite or remote

              Security Level

              Maintenance or higher

              Procedure
                Step 1   In node view (single-shelf mode) or shelf view (multishelf mode), click the Maintenance > Timing > Source tabs.
                Step 2   Find the Clock reference that is currently set to Manual or Force in the Operation drop-down list.
                Step 3   From the Operation drop-down list, choose Clear .
                Step 4   Click Apply.
                Step 5   Click Yes in the confirmation dialog box. If the normal timing reference is an acceptable valid reference, the node switches back to the normal timing reference as defined by the system configuration. If the normal timing reference is invalid or has failed, a warning dialog box appears. Click OK; the timing reference will not revert.
                Step 6   Return to your originating procedure (NTP).

                NTP-G113 View the ONS 15454 Timing Report

                Purpose

                This procedure displays the current status of the ONS 15454 timing references.

                Tools/Equipment

                None

                Prerequisite Procedures

                "DLP-G46 Log into CTC" task in Connect the PC and Log into the GUI document.

                Required/As Needed

                As needed

                Onsite/Remote

                Onsite or remote

                Security Level

                Maintenance or higher

                Procedure
                  Step 1   In node view (single-shelf mode) or shelf view (multishelf mode), click the Maintenance > Timing > Report tabs.
                  Step 2   In the Timing Report area, you can view node timing information. The date and time of the report appear at the top of the report. The time stamp is the same as the alarms time stamp and can be configured using the DLP-G118 Display Alarms and Conditions Using Time Zone task in the Alarm and TCA Monitoring and Management document.
                  Step 3   To update the report, click Refresh. The following table describes the report fields and entries.
                  Table 4 ONS 15454 Timing Report

                  Item

                  Description

                  Option

                  Option Description

                  Clock

                  Indicates the timing clock. The report section that follows applies to the timing clock indicated.

                  NE

                  The node timing clock.

                  BITS-1 Out

                  BITS-2 Out

                  BITS-2 Out

                  The BITS-2 Out timing clock.

                  Status

                  Indicates the status of the timing clock.

                  INIT_STATE

                  The timing reference has not been provisioned. For an NE reference, this status appears just before the first provisioning messages when the control card is booting. Timing is provisioned to the internal clock of the node.

                  HOLDOVER_STATE

                  The clock was locked onto a valid timing reference for more than 140 seconds when a failure occurred. Holdover state timing is a computation based on timing during the normal state combined with the node's internal clock. The node holds onto this frequency until the valid reference is restored. This status appears for NE references only.

                  FREERUN_STATE

                  The node is running off its internal clock without any modification except the calibrated value to bring timing to 0 PPM. Freerun state can occur when a Force switch to the Internal clock is initiated, when all references fail without the 140 seconds of holdover data, or when only Internal timing references are defined. This status appears for NE references only.

                  NO_SYNC_STATE

                  A synchronization timing reference is not defined. BITS-1 Out or BITS-2 Out default to this status until an OC-N/STM-N card is defined as its reference on the Provisioning > Timing tab. This status appears for external references only.

                  NE_SYNCH_STATE

                  BITS-1 Out and BITS-2 Out use the same timing source as the NE. This is displayed when NE Reference is selected in the BITS-1 Out and BITS-2 Out Reference List on the Provisioning > Timing tab.

                  NORMAL_STATE

                  The timing reference is locked onto one of its provisioned references. The reference cannot be Internal or NO SYNC STATE.

                  FAST_START_STATE

                  The node has switched references, but the reference is too far away to reach NORMAL_STATE within an acceptable amount of time. FAST_START_STATE is a fast acquisition mode to allow the node to quickly acquire the reference. After it achieves this goal, the node progresses to NORMAL_STATE.

                  FAST_START_FAILED_ STATE

                  A timing reference is too far away to reach in normal state. The FAST_START_STATE could not acquire sufficient timing information within the allowable amount of time.

                  Status Changed At

                  Date and time of the last status change.

                  -

                  -

                  Switch Type

                  Type of switch.

                  AUTOMATIC

                  The timing switch was system-generated.

                  Manual

                  The timing switch was a user-initiated Manual switch.

                  Force

                  The timing switch was user-initiated Force switch.

                  Reference

                  Indicates the timing reference.

                  Three timing references are available on the Provisioning > Timing tab.

                  -

                  Selected

                  Indicates whether the reference is selected.

                  Selected references are indicated with an X.

                  -

                  Facility

                  Indicates the timing facility provisioned for the reference on the Provisioning > Timing tab.

                  BITS-1

                  The timing facility is a building integrated timing supply (BITS) clock attached to the node's BITS-1 pins.

                  BITS-2

                  The timing facility is a BITS clock attached to the node's BITS-2 pins.

                  OC-N/STM-N card with port number

                  If the node is set to line timing, this is the OC-N/STM-N card and port provisioned as the timing reference.

                  Internal clock

                  The node is using its internal clock.

                  State

                  Indicates the timing reference state.

                  IS

                  The timing reference is in service.

                  OOS

                  The timing reference is out of service.

                  Condition

                  Indicates the timing reference state.

                  OKAY

                  The reference is valid to use as a timing reference.

                  OOB

                  Out of bounds; the reference is not valid and cannot be used as a timing reference, for example, a BITS clock is disconnected.

                  Condition Changed

                  Indicates the date and time of the last status change in MM/DD/YY HH:MM:SS format.

                  -

                  -

                  SSM

                  Indicates whether SSM is enabled for the timing reference.

                  Enabled

                  SSM is enabled.

                  Disabled

                  SSM is not enabled.

                  SSM Quality

                  Indicates the SSM timing quality.

                  8 to 10 SSM quality messages might be displayed.

                  For a list of SSM message sets, see Timing Reference chapter.

                  SSM Changed

                  Indicates the date and time of the last SSM status change in MM/DD/YY HH:MM:SS format.

                  -

                  -


                  Stop. You have completed this procedure.

                  Cisco and the Cisco logo are trademarks or registered trademarks of Cisco and/or its affiliates in the U.S. and other countries. To view a list of Cisco trademarks, go to this URL: http:/​/​www.cisco.com/​go/​trademarks. Third-party trademarks mentioned are the property of their respective owners. The use of the word partner does not imply a partnership relationship between Cisco and any other company. (1110R)

                  Obtaining Documentation and Submitting a Service Request

                  For information on obtaining documentation, using the Cisco Bug Search Tool (BST), submitting a service request, and gathering additional information, see What's New in Cisco Product Documentation, at: http:/​/​www.cisco.com/​en/​US/​docs/​general/​whatsnew/​whatsnew.html.

                  Subscribe to What's New in Cisco Product Documentation, which lists all new and revised Cisco technical documentation, as an RSS feed and deliver content directly to your desktop using a reader application. The RSS feeds are a free service.