TL 9000 is the telecommunication industry’s supplement standard of ISO 9001. It was created in 1998 by Quality Excellence for Suppliers of Telecommunications Leadership (QuEST) Forum, a group of telecom service providers and suppliers dedicated to telecom supply chain quality and performance.

QuEST Forum established a common set of quality system requirements and measurement metrics for suppliers of telecommunications systems hardware, software, and services. These requirements are built upon industry standards already in use, including the ISO 9001 standard.

The goal of TL 9000 is to define the telecommunications quality system requirements for design, development, production, and service. In addition, it specifies the cost and performance metrics for suppliers to measure progress and evaluate the results of quality implementation and improvement programs.

The standard includes requirements in: performance measurements based on reliability of product, software development and life-cycle management, specialized service functions such as installation and engineering, how to address communications between telecom network operators and suppliers, and reporting of quality measurement data to a central repository.

TL 9000-registered organizations are also required to comply with all clauses of ISO 9001.

References:
 
 
http://www.tl9000.org/about/tl9000/overview.html
 
http://www.nqa-usa.com/services/tl9000.html