Radio over Internet Protocol, or RoIP, is similar to VoIP, but augments two-way radio communications rather than telephone calls. From the system point of view, it is essentially VoIP with PTT (Push To Talk).

To the user it can be implemented like any other radio network. With RoIP, at least one node of a network is a radio (or a radio with an IP interface device) connected via IP to other nodes in the radio network. The other nodes can be two-way radios, but could also be dispatch consoles either traditional (hardware) or modern (software on a PC), POTS telephones, softphone applications running on a computer such as Skype phone, PDA, smartphone, or some other communications device accessible over IP.

RoIP can be deployed over private networks as well as the public Internet. It is useful in land mobile radio systems used by public safety departments and fleets of utilities spread over a broad geographic area. Like other centralized radio systems such as trunked radio systems, issues of delay or latency and reliance on centralized infrastructure can be impediments to adoption by public safety agencies.

RoIP is not a proprietary or protocol-limited construct but a basic concept that has been implemented in a number of ways. Several systems have been implemented in the amateur radio community and have demonstrated the utility of RoIP in a partly or entirely open-source environment.

Many commercial radio systems vendors such as Motorola and Harris have adopted RoIP as part of their system designs.

The motivation to deploy RoIP technology is usually driven by one of three factors: first, the need to span large geographic areas; second, the desire to provide more reliable, or at least more repairable links in radio systems; and third, to support the use of many base station users, that is, voice communications from stationary users rather than mobile or handheld radios.

The use of LMR (land mobile radio) equipment in both mobile and handheld forms, can be problematic for desk-bound users such as dispatchers, supervisors, and other users in large public safety agencies and energy/utilities, because such radios do not coexist well with computers (e.g. interference).

Emergency organizations are typically staffed with representatives from many different public safety agencies and other local government officials, each with a different radio.

RoIP by its nature is interoperable, as once any device whether radio, telephone, computer, or PDA is made part of the voice network enabled by IP, it is irrelevant what type of technology it utilizes. RoIP systems routinely combine VHF, UHF, POTS telephone, Cellular telephone, SATCOM, air-to-ground, and other technologies into a single voice conversation.

For more information on ROIP Contact AA Radio