ATIS Telecom Glossary
Saturday, September 20, 2014

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grandfathered systems
Systems, including but not limited to: (a) PBX and key telephone systems, directly connected to the public switched telephone network on June 1, 1978, that may remain permanently connected thereto without registration unless subsequently modified, and (b) systems that are of the same type as those connected to the public switched telephone network on July 1, 1978, that were added before January 1, 1980, and that may remain permanently connected thereto without registration unless subsequently modified.

 

 

 

 

 

 

 

 

 

 



 
These definitions were prepared by ATIS Committee PRQC
 
For more information on the work related to these definitions,
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