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  1. Science and Technology Directorate
  2. News Room
  3. News Release: DHS Recognizes DOI Lab to Perform Rigorous P25 CAP Testing

News Release: DHS Recognizes DOI Lab to Perform Rigorous P25 CAP Testing

Release Date: October 7, 2020

S&T Public Affairs, 202-254-2385
E-mail: STMedia@hq.dhs.gov

Washington, DC – It’s not easy ensuring technology for first responders meets their demanding needs, but the Department of Homeland Security (DHS) Science and Technology Directorate’s (S&T’s) Project 25 Compliance Assessment Program (P25 CAP), works tirelessly to do so.  Now, a Department of the Interior (DOI) lab is recognized by the program to perform independent third-party assessments of first responder equipment, enabling them to expand interoperable communications capabilities and coverage.

P25 CAP is a formal, independent testing process for P25 compliance with publicly published results. Through this open-standards testing process, P25 CAP provides responders with confidence that the communications equipment they use will be interoperable, regardless of the manufacturer. S&T-recognized labs carry out conformance testing to P25 CAP requirements to ensure that radios meet manufacturers’ claims that they are, in fact, interoperable and compatible with standards.

The DOI laboratory in Denver, Colorado, has been recognized to perform Inter-RF Subsystem (ISSI) and Console Subsystem Interface (CSSI) conformance testing as part of the P25 CAP. The lab partnered with DHS S&T to achieve the accreditation and received support from the Department of Commerce Institute for Telecommunication Sciences. DOI was accredited by the ANSI National Accreditation Board, fulfilling the requirements of International Organization for Standardization (ISO)/ International Electrotechnical Commission (IEC) 17025:2017, upon successfully demonstrating the required rigor of a P25 CAP test facility.

“DHS S&T’s partnership with DOI addressed a critical lack of testing laboratories to conduct the ISSI and CSSI conformance testing,” said Sridhar Kowdley, S&T Program Manager for P25 CAP. “This DHS-DOI partnership created significant cost savings by leveraging resources and capabilities of DOI laboratories. This lab, having been accredited, will make significant contributions to the P25 CAP. Their accreditation process and lessons learned will be used to assist other industry laboratory accreditations.”

“Our commitment to accredited testing ensures interoperable LMR communications are available to support critical public safety operations,” said William Vajda, DOI Chief Information Officer. “We appreciate the dedication and collaboration from DHS S&T and look forward to continuing our successful partnership”.

CSSI connects a public safety operator who is responsible for the dispatch of personnel and equipment to an existing P25 system. The CSSI also allows public safety dispatch consoles from different vendors to interoperate. ISSI allows users on otherwise disparate networks to communicate with one another by providing an interconnection between P25 systems, including those built by different manufacturers, and with different software versions. These wide area networks are known as “system-of-systems” architectures. The ISSI is also expected to play a role in the eventual interconnection between P25 systems and broadband Long Term Evolution (LTE) networks.

As equipment vendors successfully complete the conformance and interoperability tests, the equipment will be added to S&T’s Approved (Grant-Eligible) Equipment list. Public safety agencies can use federal grant funding to purchase any equipment on this list.

“P25 ISSI/CSSI is critical for DOI moving forward,” said Russ Sveda, the DOI Radio and Spectrum Program Manager. “DOI operates several hundred P25/LMR systems across the 50 states and [U.S.] territories, and most public safety operations includes state, local, and federal partners. Interconnecting with partner LMR systems and national public safety broadband networks is key to modernizing our field communications and why this testing is so important to us.”

For the latest program updates on P25 CAP and to learn about other laboratories working towards ISSI/CSSI conformance and interoperability accreditation, visit:



Last Updated: 10/07/2020
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