TBR21 is a European telecommunications standard published by ETSI, and is the standard to which all telephone equipment must adhere to, to be allowed connection to Europe's public switched telephone network.[1]

It is somewhat equivalent to the US part 68 standard.

TBR-21 has been replaced by the new ETSI standard ES 203-021[2]

The "advisory notes" (ATAAB notes) are no longer being maintained.


  This article uses material from the Wikipedia page available here. It is released under the Creative Commons Attribution-Share-Alike License 3.0.



Connect with defaultLogic
What We've Done
Led Digital Marketing Efforts of Top 500 e-Retailers.
Worked with Top Brands at Leading Agencies.
Successfully Managed Over $50 million in Digital Ad Spend.
Developed Strategies and Processes that Enabled Brands to Grow During an Economic Downturn.
Taught Advanced Internet Marketing Strategies at the graduate level.

Manage research, learning and skills at defaultlogic.com. Create an account using LinkedIn to manage and organize your omni-channel knowledge. defaultlogic.com is like a shopping cart for information -- helping you to save, discuss and share.

  Contact Us