TL1

Transaction Language 1 (TL1) is a widely used management protocol in telecommunications. It is a cross-vendor, cross-technology man-machine language, and is widely used to manage optical (SONET) and broadband access infrastructure in North America. It is defined in GR-831 by Bellcore (now Telcordia Technologies).
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Transaction Language 1.
A subset of ITU-T's MML from Bellcore, with simpler syntax. TL1 is similar to USL. It is used in communications between telephone operating systems and remote network test equipment.
[OTGR, TR-TSY-000439, section 12, Bellcore].
(1994-12-14)