Project 25 Technology Information Group

Wednesday, April 25, 2018

Project 25 Technology Information Group

P25 Standards Update from TIA TR-8 Meetings, Mesa AZ, February 6-8

Andy Davis, TR-8 Chairman

This document highlights TR-8 accomplishments and work in progress for 2018. The document will be updated after every TR-8 face to face meeting occurring in 2018. The filename reflects the date of the latest update. After the first 2018 version, each update will use blue font to indicate the updates.

Completed in 2018:

Air Interfaces

An Addendum to the trunking Control Channel Messages standard was approved for publication

This addendum introduces an "Accessory Sensed Emergency" flag to the emergency alarm message.

Wireline Interfaces
• An addendum to the ISSI Messages and Procedures for Supplementary Data was approved for publication.
This addendum introduces the messages and procedures for Individual Regrouping control across an ISSI/CSSI.





Work in Progress:

Air Interfaces
• A revision to the Conventional Interoperability Test standard is in progress.
This revision corrects editorial errors and makes clarifications on various test procedures but does not add, remove or technically alter tests.
• Creation of a High Signal Strength Intermodulation Rejection Test is in progress.
This test will measure the ability of a P25 or analog conventional FM receiver to reject an unwanted broadband base station signal, thereby preventing degradation to the reception of a desired signal. Performance specifications are expected to follow completion of the measurement method.

Wireline Interfaces
• Group Regrouping for the Trunking ISSI/CSSI Standard is in progress.
This work will enable dispatch equipment connected to Trunking Infrastructures via the ISSI/CSSI to control group regrouping services. Note the control channel messaging for these services has already been standardized.
• A revision of the ISSI Recommended Compliance Assessment Tests bulletin is in progress.
This revision will add recommended interoperability tests for Trunking CSSI applications and add recommended interoperability tests of TDMA operation of the Trunking ISSI and CSSI.
• A new Interoperability test standard for Trunked ISSI Supplementary Data Services is in progress.
This document will provide a standard set of tests for validating interoperability of Supplementary Data Services (Emergency Alarm, Call Alert, etc) operating across a Trunked ISSI.

• Definition of a Link Layer Encryption Security Service is in progress.
This is the first big new technology upgrade for improved Security for all air interfaces of P25. It protects control channel control messages, and hides group and individual IDs.
• An addendum to the Key Fill Interface standard is in progress.
This will enable Key Fill Device (KVL) interface to a KMF, an Authentication Facility and another Key Fill Device

• A revision of the Tier 2 Location Service is in progress.
This revision corrects editorial errors and makes corrections to EXI Encoding examples.

• Definition of 3GPP Mission Critical standard services interworking with TIA Land Mobile Radio standard services is in progress.
This document will describe interworking of features (example; group and individual calls) that are common between 3GPP LTE standards and P25 Trunking, P25 Conventional and Analog Conventional FM LMR standards.


A copy of the report can be downloaded using the link below:

P25 Standards Update February 2018






Web Boy Design Website Development by Web Boy Design, Inc