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Communications in a Disaster

Thank you Chairman Stevens and Members of the Committee, I serve as the Program Manager for Public Safety Communications Systems in the Office of Law Enforcement Standards at the National Institute of Standards and Technology (NIST). NIST a non- regulatory agency within the U.S. Commerce Department's Technology Administration serves industry, academia, and other parts of the government by developing and promoting measurements, standards, and technology to enhance productivity, facilitate trade, and improve the quality of life.

NIST's public safety communications program serves as the technical lead for several Administration initiatives focusing on communications, most importantly the SAFECOM Program led by Dr. Boyd. NIST is involved in many of the key SAFECOM initiatives, including the Statement of Requirements, Public Safety Architecture Framework, testing and evaluation, and standards development. The strong partnership between SAFECOM and NIST is an excellent example within the Administration of multi-agency coordination and collaboration, and is something for which we at NIST are very proud.

I will focus the remainder of my remarks this morning on the state of standards for public safety communications systems.

Interoperability for public safety communications is defined as "the ability to share information via voice and data signals on demand, in real time, when needed, and as authorized." The public safety community expects that this level of interoperability will be available using equipment from multiple manufacturers, that they are transparent to the user, requiring little or no special knowledge of the system, and that they are not dependent on common frequency assignments.

Achieving this definition of interoperability is not possible without the existence of standards that will define how the various components of a public safety communications system will interoperate, regardless of manufacturer. In fact, I would venture to say that in the absence of standards, achieving this level of interoperability would be impossible.

Public safety users have recognized this for some time. Approximately fifteen years ago, representatives from local, state, and federal public safety associations and agencies joined together to address the absence of available standards. They did this for two primary purposes. First was to ensure that interoperability could be achieved, assuming the use of equipment from multiple manufacturers. Second, through standards, the public safety community wanted to be able to take advantage of cost reductions associated with a more competitive land mobile radio market.

Understanding the difficulty in specifying the complex operations of the various components of a land mobile radio system, the public safety community partnered with the Telecommunications Industry Association (TIA) to serve as the standards development organization (SDO) for this effort. Thus Project 25, or P25 as we know it today, was launched.

A commonly misunderstood aspect of P25 is that it is comprised of a single standard. Instead, it is a suite of standards that specify the eight interfaces between the various components of a land mobile radio system (hand held to hand held, hand held to mobile unit, mobile unit to tower, etc.):

  • Common air interface this interface defines the wireless access between mobile and portable radios and between the subscriber (portable and mobile) radios and the fixed or base station radios;
  • Subscriber data peripheral interface this interface characterizes the signaling for data transfer that must take place between the subscriber radios and the data devices that may be connected to the subscriber radio;
  • Fixed station interface this interface describes the signaling and messages between the RFSS and the fixed station by defining the voice and data packets (that are sent from/to the subscriber(s) over the common air interface) and all of the command and control messages used to administer the fixed station as well as the subscribers that are communicating through the fixed station;
  • Console interface this interface is similar to the fixed station interface but it defines all the signaling and messages between the RFSS and the console, the position that a dispatcher or a supervisor would occupy to provide commands and support to the personnel in the field;
  • Network management interface this interface to the RFSS allows administrators to control and monitor network fault management and network performance management.
  • Data network interface this interface describes the RF subsystem's connections to computers, data networks, external data sources, etc.;
  • Telephone interconnect interface this interface between the RFSS and the Public Switched Telephone Network (PSTN) allows field personnel to make connections through the public switched telephone network by using their radios rather than using cellular telephones;
  • Inter RF subsystem interface this interface permits users in one system to communicate with users in a different system, from one jurisdiction to another, from one agency to another, from one city to another, etc.

Over the last fifteen years only one of the P25 interfaces, the Common Air Interface that deals with the functions of the hand held units (i.e., walky-talky), has been advanced to a level where it would help satisfy one or both of the goals of P25. The remainder of the interfaces either remains undefined, or lacks enough specificity to allow for a common implementation of the interface; in other words each manufacturers implementation of the interface is different and proprietary thus resulting in systems that do not meet the "interoperability" requirements as defined by the steering committee.

I would like to emphasize that the Common Air Interface is a major step forward and extremely important. It provides a level of interoperability and competition in the hand- held market that was not available before. However, it alone cannot satisfy the definition of interoperability that the public safety community is calling for.

An MOU formalizing the relationship between the public safety users and TIA, created a Steering Committee comprised only of public safety and government representatives and invested that committee with the sole authority to designate a P25 standard. In addition, the MOU stipulates that the Steering Committee has wide latitude in defining and adopting P25 standards, and does not limit it to only TIA adopted standards.

To reinforce the need to expeditiously move forward on all remaining P25 interface standards as prioritized by the Steering Committee, the co-Chair of the P25 Steering Committee informed the membership of TIA that an agreed upon Inter-RF-Subsystem- Interface (ISSI) document will be required by January of 2006. If this deadline is not met the Steering Committee would vote to begin an alternate process for developing an ISSI standard. The Steering Committee's plan would be to issue a call for proposals to define an open ISSI standard, select the best proposal and designate it the P25 ISSI standard.

It needs to be made clear that it is everyone's desire that a consensus on these standards is needed and that formal TIA standards be adopted, and that the remaining P25 interface standards be forthcoming within a timeframe that satisfies the needs of public safety users and policy makers at all levels of government.

It is not only important that the various P25 interfaces are completed in a timely manner, but that a mechanism exist to ensure that products built to the standard, meet all of the requirements of the standard.

Over the last two years, NIST, with funds from the Department of Homeland Security and the Department of Justice, has tested a number of the hand held P25 radios that claim to meet the available Common Air Interface Standard. Using the test procedures called for in the standard, NIST found that none of the available radios met all aspects of the standard.

NIST, with the support of SAFECOM and the P25 Steering Committee, is developing a P25 Conformity Assessment Program. NIST is preparing and documenting standardized test protocols for the most important aspects of the Common Air Interface Standard. The standardized test protocols will then be provided to NIST's National Voluntary Laboratory Accreditation Program (NVLAP), which can accredit third party laboratories across the country interested in offering these testing capabilities. These test protocols would go a long way in assuring the public safety community that the equipment being purchased meets the P25 standard.

NIST is working closely with the P25 Steering Committee and manufacturers to ensure that the test procedures are correct and that the results are accurate. In addition, not all aspects of the P25 common air interface will be immediately available for testing through this program. To begin with, NIST is focusing on some basic functional tests of the radios, which will allow us to get the Conformity Assessment Program up and running.

We will then begin to add interoperability tests, as well as tests for more complex radio functions.

In summation Mr. Chairman, there are positive steps being taken by leaders within the public safety community, key federal programs, the Congress and industry to significantly change the current environment and move the state of standards for public safety forward. This time next year, there should be new adopted P25 interface standards and manufacturers will have begun to plan new products lines that incorporate the new standards. Local, state, and federal agencies procuring P25 equipment will have a mechanism in place to ensure that the products they are purchasing truly do what is called for in the applicable standard. In conjunction with the other efforts Dr. Boyd spoke of, I am confident that we are making significant headway in the pursuit of communications interoperability.

NIST looks forward to working with this Committee, Congress, our federal partners, state and local public safety officials, and leaders in industry to make this happen. Again, I am honored to be here before this Committee today, and I will happy to answer any questions that you may have.

Created December 9, 2016