5.0 TL1 Protection Switching Messages

The following are the TL1 protection switching messages used by TL1 operators.
TL1 protection switching messages help switching capability between working, protection, and backup entities. You have messages to control the backup capabilities of redundant equipment units and facilities.

5.1 Switching Messages

NEs provide protection switching upon detecting trouble in the line. You can implement the functions using the switching messages shown below. These messages are defined in GR-833[1].
EX-SW - This command instructs an NE to exercise the algorithm for switching from a an equipment or facility entity from working to protection.
REPT-SW - Generated by the NE after it has autonomously switched an active unit of a duplex equipment pair to standby and switched its mate to active.
SONET  - Protection switching messages for SONET NEs.
Non-SONET  - Protection switching messages for non-SONET NEs.

5.2  SONET Protection Switching Messages

SONET provides automatic protection switching upon detecting trouble in the line. You can implement the functions using the switching messages shown below. These messages are defined in GR-833[1].
OPR-PROTNSW - Instructs a SONET NE to initiate a SONET line or path protection switch request. User switch requests initiated with this command (i.e., forced switch, lockout, and manual switch) remain active until they are released via the RLS PROTNSW command or overridden by a higher priority protection switch request. To initiate protection switch exercise, use EX SW.
RLS-PROTNSW - Instructs a SONET NE to release a SONET line or path protection switch.

5.3 Non-SONET Line Protection Switching Messages

The following commands instruct NEs to allow or inhibit automatic / manual switching to protection or working.

DO NOT USE THESE COMMANDS FOR SONET LINE PROTECTION SWITCHING.

ALW-SWDX This command instructs the NE to allow automatic or manual switching to protection for a managed inventory or facility entity on a duplex system. To inhibit from switching to protection, use INH-SWDX.

ALW-SWTOPROTN-xx This command instructs the NE to allow automatic or manual switching to protection for a managed inventory or facility entity. This function is sometimes called "release lockon" or "release lockout."The AID in this command identifies either the equipment unit or facility for which switching to protection is being allowed. The entity may be the working unit or the protection unit. · For a working unit, this command allows the unit to access any protection unit, and the state of the working unit changes from IS-NR-ACT-LOCK to IS-NR-ACT. · For a protection unit, this command allows the protection unit to be accessed by any working unit, and its state changes from IS-NR-STBY-LOCK to IS-NR-STBY.To inhibit from switching to protection, use INH-SWTOPROTN.

ALW-SWTOWKG-xx This command instructs the NE to allow automatic or manual switching to working for a managed inventory or facility entity that has been switched to protection. The ALW-SWTOWKG function is sometimes called "release lockon a protection unit" or "release lockout a working unit."To inhibit from switching back to working, use INH-SWTOWKG.

INH-SWDX-xx This command instructs the NE to inhibit automatic or manual switching to protection for a managed inventory or facility entity on a duplex system. Any NE for which switching to protection is inhibited with the INH-SWDX command should include the appropriate condition type information in response to a RTRV-COND request.

INH-SWTOPROTN-xx This command instructs the NE to inhibit automatic or manual switching to protection for a managed inventory or facility entity. Any NE for which switching to protection is inhibited with the INH-SWTOPROTN command should include the appropriate condition type information in response to a RTRV-COND request.

INH-SWTOWKG-xx This command instructs the NE to inhibit automatic or manual switching to working for a managed inventory or facility entity that has been switched to protection. Any NE for which switching to working is inhibited with the INH-SWTOWKG command should include the appropriate condition type information in response to a RTRV-COND request.

SW-DX-xx This command instructs an NE to switch an equipment unit or facility with the mate unit within the NE.

SW-TOPROTN-xx Perform a protection switch

SW-TOWKG-xx Release a unit from protection