In an effort to keep DHS.gov current, the archive contains outdated information that may not reflect current policy or programs.
Interoperability (In-ter-op-er-a-bil-i-ty): the ability of equipment or groups to operate in conjunction with one another.
Understanding what it means is easy enough, but achieving interoperability has long been a problem in the emergency response arena. And yet, it’s of critical importance that responders, called to both day-to-day and large-scale incidents, communicate with each other regardless of the make or model of equipment, such as radios.
“The challenge is born of communications equipment manufacturers using varying approaches to implement systems, leaving their products incompatible,” said Sridhar Kowdley, Program Manager of the Project 25 Compliance Assessment Program (P25 CAP) in the Department of Homeland Security’s Science and Technology Directorate. “To date, first responders still rely on land mobile radio systems as their network of choice for mission critical voice needs.”
Project 25 (P25) is a standards development process for the design, manufacture, and evaluation of interoperable digital two-way land mobile radio systems communications products created by and for public safety professionals. The P25 standard is a critical component to achieve interoperability among different suppliers’ products. The P25 CAP provides responders with the confidence that the communications equipment they use has been tested against the standards and successfully tested for interoperability, no matter the manufacturer. The P25 CAP is a congressionally mandated program that has enjoyed continued congressional support through DHS appropriation Conference Reports. As a voluntary program, P25 CAP allows suppliers to publicly attest to their products' compliance through P25 CAP testing at DHS-recognized laboratories. As proof, suppliers are required to submit Summary Test Report (STR) and Supplier’s Declaration of Compliance (SDOC) documents. In turn, P25 CAP makes these documents available to the first response community to inform their purchasing decisions via the S&T’s P25 CAP website.
So, P25 compliant, P25 CAP compliant, P25 compliant with the Statement of Requirements (P25 SOR) -- what does it all mean? Although the P25 standard has been around for more than 25 years, there’s still significant confusion around what compliance is. End users may assume that if something is found in the P25 Statement of Requirements (SoR), that it must be found in a radio that is marketed as a “P25 radio.”
“Unfortunately, that assumption is not correct,” said Kowdley.
There is a sort of continuum of compliance context when it comes to P25. Here goes:
- P25 Statement of Requirements Context: The P25 SoR is approved by the P25 Steering Committee and was last updated in 2013. It’s the basis for the development of P25 standards and thus not all items contained in the P25 SoR have accompanying standards. Therefore, just because a radio may be marketed and sold as a P25 radio does not mean it meets all the requirements that are called out in the P25 SoR. The P25 SoR is the basis for P25 standards.
- P25 Standard Context: P25 standards are developed by the Telecommunications Industry Association (TIA), an ANSI-accredited, standards development organization. TIA maintains working groups to develop and update P25 standards.
- P25 Standard Test Context: TIA develops testing procedures for P25 standards in the form of Recommended Compliance Assessment Tests (RCATs). The ability to have defined test procedures to help validate if P25 equipment does indeed meet the standard is important. However, it should be noted that not all requirements published P25 standards are tested.
- P25 CAP Context: P25 CAP is managed by DHS S&T but is a collaborative program that relies on voluntary participation by manufacturers, laboratories, and accreditation bodies. Compliance Assessment Bulletins (CABs) define the test procedures for the P25 CAP. DHS S&T develops CABs using the TIA standards and even in some cases RCATs as a basis, solicits public comment, and publishes these test procedures. It should be noted that not all TIA P25 standards requirements are tested. As part of the program, manufacturers test their equipment at a recognized and previously accredited P25 CAP laboratories, that rigorously test the equipment to the procedures/test cases within the P25 CAP CABs. Once the equipment passes, an STR and SDOC document is submitted to DHS S&T for approval and posting to its website. DHS S&T reviews the documentation and once approved makes them available on its website along with a full list of P25 CAP approved equipment. It is this list, and only this list, which is referenced by several Federal grant programs including the Federal Emergency Management Agency as allowable equipment to be purchased using Federal grant funds.
When end users are looking for equipment that’s independently tested for compliance with the P25 standard, DHS S&T recommends that the P25 CAP approved equipment list be the source of reference.
“Ultimately P25 CAP provides responders confidence that the communications equipment they use has been tested for interoperability and against the P25 standard,” Kowdley concluded.”So next time you want to buy P25 capable equipment (infrastructure or subscriber) you may want to confirm that it’s been tested as part of the P25 CAP by simply checking S&T’s P25 CAP website.”
On the horizon:
DHS S&T continues to work to develop additional CABs to increase the breadth of testing for the program. Next in the queue are CABs that cover Time Division Multiple Access or Phase II equipment as well as the Console Sub-System Interface. These CABs expand the P25 CAP’s testing scope ultimately resulting in a more diverse set of equipment becoming a part of the program.
Project 25 (P25) and Project 25 Compliance Assessment Program (P25 CAP)
In 2008, the U.S. Department of Homeland Security Science and Technology Directorate (S&T) partnered with the Department of Commerce Public Safety Communications Research program to establish the P25 Compliance Assessment Program (P25 CAP), which tests equipment designed to comply with P25 standards. P25 CAP provides responders with the confidence that the communications equipment they use will be interoperable, no matter the manufacturer.
DHS S&T and the P25 CAP Advisory Panel (AP)
It’d become clear in recent years that the P25 CAP required a renewed energy to realize substantial progress. To that end, a few key steps were taken to re-invigorate the Program across 2016. For one, the P25 CAP Advisory Panel was officially established in early 2016 to provide S&T’s Office for Interoperability and Compatibility (OIC) with federal, state, local, tribal, and territorial perspectives on portable, handheld, and vehicle-mounted radios and infrastructure equipment. Through the P25 CAP AP, S&T OIC supports the collective interest of organizations that procure P25-compliant equipment. The Advisory Panel members provides recommendations on promoting the P25 CAP, reviews and comments on proposed compliance assessment bulletins and updates to existing test documents, establishes new test documents for new types of P25 CAP equipment, and proposes P25 user input for improving functionality through the standards-making process.