Project 25 ( P25 or APCO-25 ) is a suite of standards for digital radio communications for use by federal, state / province and local public safety agencies in North America to enable them to communicate with other agencies and mutual aid response teams in emergencies.

P25 was established to address the need for common digital public safety radio communications standards for first-responders and homeland security / emergency response professionals.

The Telecommunications Industry Association's TR-8 engineering committee facilitates such work through its role as an ANSI-accredited standards development organization ( SDO ) and has published the P25 suite of standards as the TIA-102 series of documents, which now include forty-nine separate parts on Land Mobile Radio and TDMA implementations of the technology for public safety.

In addition, the P25 suite of standards provides an open interface to the radio frequency ( RF ) subsystem to facilitate interlinking of different vendors ' systems.

The goal of P25 is to enable public safety responders to communicate with each other and, thus, achieve enhanced coordination, timely response, and efficient and effective use of communications equipment.

This leads to the situation that almost all P25 networks are based in Northern America where it has the advantage that a P25 system has the same coverage and frequency bandwidth as the earlier analogue systems that were in use so that channels can be easily upgraded one by one.

* P25 Phase 2 Forum, for more information on P25 Phase 2

P25 may be used in " talk around " mode without any intervening equipment between two radios, in conventional mode where two radios communicate through a repeater or base station without trunking or in a trunked mode where traffic is automatically assigned to one or more voice channels by a Repeater or Base Station.

* Fixed Station Interface – standard specifies a set of mandatory messages supporting digital voice, data, encryption and telephone interconnect necessary for communication between a Fixed Station and P25 RF Subsystem

The difficulties inherent in developing P25 networks using features such as digital voice, encryption, or trunking sometimes result in feature-backlash and organizational retreat to minimal " feature-free " P25 implementations which fulfill the letter of any APCO-25 migration requirement without realizing the benefits thereof.

The British Racing Partnership BRM P25 with which Stirling Moss took second place in the 1959 British Grand Prix.

This research was the result of the OP25 project OP25 Project homepage which uses GNUradio and the Ettus USRP to implement an open source P25 packet sniffer and analyzer.

The BRP BRM P25 which Stirling Moss drove to second place in the 1959 British Grand Prix, BRP's first podium finish. The race was won by Australian Jack Brabham taking his second Grand Prix victory in a works Cooper T51.

Dodge Kingsway models assembled in Australia included a version based on the 1954 US Plymouth P25 Sedan, which was produced by Chrysler Australia from 1954 to 1957.

As of mid-2004 there were 660 networks with P25 deployed in 54 countries.

With other systems, jammers have to expend a lot of power to block communications, but the P25 radios allow jamming at relatively low power, enabling the researchers to prevent reception using a $ 30 toy pager designed for pre-teens.

Stirling Moss believed that the BRM engine was superior to the Coventry-Climax unit used in his Cooper, and a P25 was briefly run in 1959 by the British Racing Partnership, for Moss ( and also Hans Herrmann ), and Rob Walker also backed the construction of a Cooper-BRM to gain access to the engine.

Recognizing and understanding this need, Project 25 ( P25 ) was initiated collaboratively by public safety agencies and manufacturers to address the issue with emergency communication systems.

This is exacerbated by the fact that P25 radios when set to secure mode continue to operate without issuing a warning if another party switches to clear mode.

The varying levels of error correction are implemented by breaking P25 message frames into subframes.

Such tracking by authorized users is considered a feature of P25, referred to as " presence.

The race was won by Swedish driver Joakim Bonnier driving a BRM P25.

Brabham dominated the race, leading all 75 laps to win by 22 seconds over British driver Stirling Moss driving a British Racing Partnership entered BRM P25.

They attempted to become a competitive team by offering a 5-year, P25 million contract to Purefoods TJ Hotdogs ' top gun Alvin Patrimonio.

Made for P25, 000, 000 and released immediately after Aquino won acting awards ( for her performance in 2002's Mano Po ), You and Me Against the World made only P4, 389, 005.

The network is a digital 9600 bps Project 25 ( commonly referred to as P25 or APCO-25 ) Phase 1 trunked radio system operating in the UHF band between 403 MHz and 420 MHz in 12. 5 kHz steps.

The P25 was initially unsuccessful, not winning a race until a long awaited victory at the Dutch Grand Prix in 1959.

The P25 was becoming highly competitive just as the rear-engined Cooper started to become dominant ; the P48 was a quick reaction to this, using major components from the P25 but in rear-engined format.

In this regard, P25 fills the same role as the European Terrestrial Trunked Radio ( TETRA ) protocol, although not interoperable with it.

In addition, a steering committee consisting of representatives from the above mentioned agencies along with FPIC ( Department of Homeland Security Federal Partnership for Interoperable Communication ), Coast Guard and the Department of Commerce's National Institute of Standards and Technology ( NIST ), Office of Law Enforcement Standards was established to decide the priorities and scope of technical development of P25.

P25 is collaborative project to ensure that two-way radios are interoperable.

P25 equipment has also been selected for a railroad system, including rolling stock, personnel, and transportation vehicles.

Radios can communicate in analog mode with legacy radios, and in either digital or analog mode with other P25 radios.

P25 systems do not support Continuous Tone-Coded Squelch System ( CTCSS ) tone or Digital-Coded Squelch ( DCS ) codes for access control.

According to the report, a P25 jammer could effectively operate at 1 / 25th the power ( 14 dB less ) than the communicating radios.

* http :// www. p25. com / resources / P25TrainingGuide. pdf Daniels ' P25 Radio System Training Guide

* http :// urgentcomm. com / mag / radio_oil_water / Some ways of avoiding P25 interoperability challenges

* http :// www. valid8. com / Conformance_Test. html P25 Compliance Test Tools for ISSI

* http :// www. etherstack. com / networks. htm # 1 P25 Protocol Stack Software

* http :// www. dvsinc. com / prj25. htm DVSI P25 Vocoder Software and Hardware

EDACS has the largest customer base of any technology in M / A-COM's portfolio ( i. e. EDACS, OpenSky, P25 and TETRA ).