The ISSI Messages and Procedures specification [TIA-102.BACA] defines the messages and procedures necessary to provide mobility management and voice services over the P25 ISSI. This specification defines the messages and procedures necessary to provide Supplementary Data Services over the P25 ISSI. Supplementary Data Services include:

1. Emergency Alarm¹

2. Emergency Alarm Cancellation¹

3. Group Emergency Cancellation¹

4. Call Alert ([TSB102A], Section 5.4.2.3.10)

5. Short Message ([TSB102A], Section 5.4.2.2.7)

6. Status Query¹

7. Status Update¹

8. Radio Unit Monitor ([TSB102A], Section 5.4.2.3.8)

9. Radio Check¹

10. Radio Detach¹

11. Radio Inhibit ([TSB102A], Section 5.5.5)

12. Radio Un-Inhibit ([TSB102A], Section 5.5.5)

Note that [TSB102A], [TIA-102.AABC], and [TIA-102.AABD] refer to these as "Supplementary Services".

In order to support supplementary data distribution to recorders and consoles, this specification requires additions to the mobility management protocol of the ISSI to provide mechanisms for expressing various types of interest in supplementary data. These are included in the ISSI Messages and Procedures Specification [TIA-102.BACA].

This document defines the Messages and Procedures associated with the Supplementary Data services in the ISSI standard. Supplementary Data services in the ISSI will be fully defined when the following suite of ISSI related documents is completed:

• ISSI Conformance Tests for Supplementary Data Services

• ISSI Methods of Measurements for Supplementary Data Services

• ISSI Performance Recommendations for Supplementary Data Services

• ISSI Interoperability Test Methods for Supplementary Data Services

¹ These Supplementary Data Functions are not explicitly called out in TSB102A, but are provided for throughout the standards.