A general land mobile radio communications system consists of subscriber units, base stations, fixed equipment for single-site to wide area operation, console operator positions, and computer equipment. The subscriber units include portable radios for handheld operation and mobile radios for vehicular operation. The base stations are for geographically fixed installations. Other fixed equipment is used for wide area operation and console operator positions, and computer equipment is used for interface between each of these equipment items. A standard should exist to describe any given specific instance of such a general land mobile radio system. This document will refer to such a specific instance of a general land mobile radio system as a Land Mobile Radio system, to distinguish it from the entire universe of general land mobile radio systems. Specific Land Mobile Radio systems are referenced in the appendices for the instantiation of the security services described in this document. Instances of Land Mobile Radio systems that may apply these security services are given by TSB 102-A (reference [1]) and TIA 905 (reference [2]) System and Standards Definition (shell) documents.

This document provides an overview of the security services available in Land Mobile Radio systems. It provides the context in which to understand why security services are required and gives a general high level description of how they are provided.

The purpose of security services is to neutralize information security threats to a system. The nature of these threats is discussed in this document and the security services to counter these threats are defined.

The security services defined here apply to all aspects of Land Mobile Radio systems, including trunking and conventional systems as well as voice and data systems. In general the subject of security includes encryption, and this topic is discussed in general terms to explain the different levels of encryption algorithms available within the standard, and their application to security services.

In the context of this document, the specific security requirements are generalized into four security topics:

1. Confidentiality (also known as Privacy)

2. Authentication

3. Integrity

4. Key management

These four categories correspond to the security services available to Land Mobile Radio systems. This document does not provide specific message formats or operational details of these security services. Detailed information is provided in the companion documents identified in section 1.6.