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Project 25


Project 25 CAP     About Project 25     Standards     Links

About Project 25

Project 25 (P25) is a standards development process for the design, manufacture, and evaluation of interoperable digital two-way wireless communications products created by and for public safety professionals. The published suite of P25 standards is administered by the Telecommunications Industry Association (TIA Mobile and Personal Private Radio Standards Committee TR-8). Radio equipment that demonstrates compliance with P25 should be able to meet a set of minimum requirements to fit certain needs of public safety, including interoperability, allowing users on different systems to talk via direct radio contact.  P25 consists of 8 interfaces.



Eight Interface Standards

  • Common Air Interface (CAI)
  • Inter-RF Subsystem Interface (ISSI)
  • Fixed/Base Station Subsystem Interface (FSSI) 
  • Console Subsystem Interface (CSSI) 
  • Network Management Interface
  • Data Network Interface
  • Subscriber Data Peripheral Interface 
  • Telephone Interconnect Interface

Links