INTRODUCTION

This Telecommunications Systems Builetin (TSB) applies to TiA/EIA/IS-637. It introduces the following modifications:

• 14.4kbps data rate support

• Service negotiation support

• IS-637 layering problem correction, editorial corrections

This TSB uses the same structure and section numbering as TIA/EIA/IS-637. Sections of this TSB that remain unchanged relative to TIA/EIA/IS-637 are represented using ellipses contained within brackets ([...])Modified sections are either reproduced in their entirety or use the [...] notation to represent unchanged portions. Within modified sections, change bars indicate the specific paragraphs, figures, or table cells that have changed. Within modified paragraphs and table cells, strike-through indicates deleted text and underline indicates new text.