Project 25 digital radio systems may support, as a standard option, a set of data communications bearer services. This document provides an overview of the standardized set of data communication bearer services such that, where these data bearer services are enabled, data connectivity will operate in accordance with the following goals:

• Through any Project 25 radio

• Across any Project 25 digital radio system

• Independent of the particular equipment manufacturer

• Adherence to the Common Air Interface

• Independent of Trunking or conventional system modes

This document updates ANSI/TIA/EIA-102.BAEA-2000 to incorporate the information from the ANSI/TIA-102.BAEA-1-2002 addendum document that defines the application of the Universal Serial Bus (USB) Specification and the Point-to-Point Protocol (PPP) to the Physical and Link Layers, respectively, of the A Reference Point between the Mobile Data Peripheral (MDP) and the Mobile Radio Controller (MRC) in the Project 25 General System Model in TSB-102-A.

Project 25 digital radio systems may support, as standard options, a standardized PPP interface and a standardized USB interface on the A Reference Point interface between the Mobile Data Peripheral (MDP) and the Mobile Radio Controller (MRC) in the Project 25 General System Model in TSB-102-A.

It should be noted that inherent in the natures of the OSI seven layer architecture and the IP four layer architecture is the opportunity to implement any of four (4) configurations of the SLIP, the PPP, the USB, and the TIA/EIA-232 protocols in the Link Layer and the Physical Layer as depicted in Table 1.1-1.

Refer to Annex A for a technical parameter listing for each of the four (4) Reference Point A standard option interface protocols. Annex A is informative (as opposed to normative as defined in 2.4.8 of the TIA Style Manual) in nature (as defined in 2.5.1 of the TIA Style Manual) and is not considered part of this Standard.