TL1 protocol is an open, human-readable precursor to SNMP.

Being ASCII-based, it's not as efficient as a simple bit protocol. That's less important in the modern era, as all alarm management protocols use relatively little bandwidth by today's standards. What you gain for the small price of increased bandwidth is human-readability. Although you do need to know something about TL1 to know the messages, it's fairly easy with a bit of practice.

Where Can I Find TL1?

Despite its age, TL1 is found in a surprising number of networks. This is especially true if you have SONET optical network gear. You can find TL1 used for contact closure monitoring, event monitoring, SCADA, and remote site monitoring.

Sometimes, specific examples are the best way to start learning. These are very specific, but you can likely use similar TL1 implementations in your network:

  1. Monitor AFC gear via TL1 with T/Mon.

  2. Report to Your Alcatel TSM-8000 with T/Mon Mediation.

What good is a protocol if you don't know the commands you can use?

What good is a protocol if you don't know the commands you can use? TL1 commands are basic elements of TL1 alarm monitoring. The list below is a reference for some of the most common TL1 commands used in network reliability management.















Because it's ASCII-based, TL1 can be effectively parsed with a text-analyzing master station like T/Mon. With the T/Mon ASCII Processor software module, this master station is about to break down TL1 into its component parts and incorporate it into any modern monitoring system (ex. SNMP, DNP3...).

Products Related to TL1 Commands:


T/Mon LNX Remote Alarm Monitoring System T/Mon Slim
T/MonXM software on the T/Mon LNX hardware monitors, mediates, and forwards alarm data in over 25 standard and proprietary protocols, including legacy equipment no one else can support. T/Mon SLIM gives local/regional network managers effective, real-time control and visibility of their alarms.

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