Radio over Internet Protocol, or RoIP, is similar to

Voice over IP Voice over Internet Protocol (VoIP), also called IP telephony, is a method and group of technologies for the delivery of speech, voice communications and multimedia sessions over Internet Protocol (IP) networks, such as the Internet. The terms In ...

(VoIP), but augments

two-way radio A two-way radio is a radio that can both transmit and receive radio waves (a transceiver), unlike a broadcast receiver which only receives content. It is an audio (sound) transceiver, a transmitter and receiver in one unit, used for bidirecti ...

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 PDA may refer to: Science and technology * Patron-driven acquisition, a mechanism for libraries to purchase books *Personal digital assistant, a mobile device * Photodiode array, a type of detector * Polydiacetylenes, a family of conducting poly ...

smartphone A smartphone is a portable computer device that combines mobile telephone and computing functions into one unit. They are distinguished from feature phones by their stronger hardware capabilities and extensive mobile operating systems, whic ...

, 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 Mobile radio or mobiles refer to wireless communications systems and devices which are based on radio frequencies(using commonly UHF or VHF frequencies), and where the path of communications is movable on either end. There are a variety of view ...

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 A trunked radio system is a two-way radio system that uses a control channel to automatically assign frequency channels to groups of user radios. In a traditional half-duplex land mobile radio system a group of users (a ''talkgroup'') with mobile ...

, 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 Amateur radio, also known as ham radio, is the use of the radio frequency spectrum for purposes of non-commercial exchange of messages, wireless experimentation, self-training, private recreation, radiosport, contesting, and emergency communic ...

community such as Galaxy PTT Comms, AllStar Link, BroadNet, IRLP, and

EchoLink EchoLink is a computer-based Amateur Radio system distributed free of charge that allows radio amateurs to communicate with other amateur radio operators using Voice over IP (VoIP) technology on the Internet for at least part of the path between t ...

that have demonstrated the utility of RoIP in a partly or entirely open-source environment. Many commercial radio systems vendors such as

Motorola Motorola, Inc. () was an American Multinational corporation, multinational telecommunications company based in Schaumburg, Illinois, United States. After having lost $4.3 billion from 2007 to 2009, the company split into two independent p ...

and

Harris Harris may refer to: Places Canada * Harris, Ontario * Northland Pyrite Mine (also known as Harris Mine) * Harris, Saskatchewan * Rural Municipality of Harris No. 316, Saskatchewan Scotland * Harris, Outer Hebrides (sometimes called the Isle of ...

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 or operate in areas without sufficient coverage from radio towers; 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. Geographies may be more economically reliably served when spanned by the use of IP technology due to the constantly decreasing cost and increasing functionality of the evolving

packet-switched network In telecommunications, packet switching is a method of grouping data into '' packets'' that are transmitted over a digital network. Packets are made of a header and a payload. Data in the header is used by networking hardware to direct the pack ...

equipment and software (a track followed by

Moore's law Moore's law is the observation that the number of transistors in a dense integrated circuit (IC) doubles about every two years. Moore's law is an observation and projection of a historical trend. Rather than a law of physics, it is an empir ...

). Traditionally distant radio users have been linked via dedicated microwave equipment and/or leased telephone lines. Generally, the cost of operating a radio network is decreased by the adoption of IP technology, replacing the traditional microwave and leased telephone lines. Economical and reliable distant radio links such as those needed by state troopers, energy utilities, and Medivac helicopters are well served by RoIP technology (see

Air Evac Lifeteam Air Evac EMS, Inc., operating as Air Evac Lifeteam and sometimes called simply Air Evac, is an American helicopter emergency medical service (HEMS) or air ambulance provider headquartered in O'Fallon, Missouri. It is the largest subsidiary of ...

for an example of a 14-state radio system). U.S. military units are using RoIP to protect convoys spread out across large geographieshttp://www.gcn.com/print/26_28/45325-1.html?topic=defense-technology The conversion to RoIP also drives the adoption of a network approach rather than hub and spoke architecture that is typical of the point-to-point links inherent in the legacy microwave and leased line technologies. Hub and spoke architectures are inherently fragile, while the network approach developed at the foundation of the public Internet by

DARPA The Defense Advanced Research Projects Agency (DARPA) is a research and development agency of the United States Department of Defense responsible for the development of emerging technologies for use by the military. Originally known as the Adv ...

is generally more reliable, more adaptable, and faster to repair and restore in a wide area disaster such as

Hurricane Katrina Hurricane Katrina was a destructive Category 5 Atlantic hurricane that caused over 1,800 fatalities and $125 billion in damage in late August 2005, especially in the city of New Orleans and the surrounding areas. It was at the time the cost ...

. The use of LMR (land

) 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). Also,

Emergency Operations Center An emergency operations center (EOC) is a central command and control facility responsible for carrying out the principles of emergency preparedness and emergency management, or disaster management functions at a strategic level during an emer ...

(EOCs) are typically staffed with representatives from many different public safety agencies and other local government officials, each with a different radio. Such EOCs are more effectively (and quietly!) equipped when the radios for each of the different constituencies are made available in the center via RoIP at each user's computer, rather than via a handheld radio that may be out of range, difficult to hear, and out of batteries throughout the emergency. Finally, RoIP by its nature is inter-operable, 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 Cellular may refer to: *Cellular automaton, a model in discrete mathematics * Cell biology, the evaluation of cells work and more * ''Cellular'' (film), a 2004 movie *Cellular frequencies, assigned to networks operating in cellular RF bands *Cell ...

telephone, SATCOM, air-to-ground, and other technologies into a single voice conversation. This makes it especially valuable to the much-documented problems with communications

interoperability Interoperability is a characteristic of a product or system to work with other products or systems. While the term was initially defined for information technology or systems engineering services to allow for information exchange, a broader defi ...

. In order to minimize the growth of Radio over IP technologies that are incompatible with each other, the

U.S. Department of Homeland Security The United States Department of Homeland Security (DHS) is the U.S. federal executive department responsible for public security, roughly comparable to the interior or home ministries of other countries. Its stated missions involve anti-terr ...

and the

National Institute of Standards and Technology The National Institute of Standards and Technology (NIST) is an agency of the United States Department of Commerce whose mission is to promote American innovation and industrial competitiveness. NIST's activities are organized into physical sci ...

are sponsoring BSI for ROIP, a draft standard for enabling different Radio over IP technologies to interoperate. Radio Control over IP (RCoIP) provides the essential signaling and management for voice messages required for Critical Communications and is a step up from Radio over IP (RoIP). RCoIP is designed so that essential messages get through by using confirmed signaling. Catalyst is an innovator in Radio over IP (RoIP) solutions for primary dispatch, backup dispatch, and interoperability.

Implementations

is a client–server software program designed by

enthusiasts for linking amateur

radio frequency Radio frequency (RF) is the oscillation rate of an alternating electric current or voltage or of a magnetic, electric or electromagnetic field or mechanical system in the frequency range from around to around . This is roughly between the upp ...

gateways and

repeater In telecommunications, a repeater is an electronic device that receives a signal and retransmits it. Repeaters are used to extend transmissions so that the signal can cover longer distances or be received on the other side of an obstruction. Some ...

s via the

internet The Internet (or internet) is the global system of interconnected computer networks that uses the Internet protocol suite (TCP/IP) to communicate between networks and devices. It is a '' network of networks'' that consists of private, pub ...

by using a

protocol. It is developed for licence free radios like

Citizens Band Citizens band radio (also known as CB radio), used in many countries, is a land mobile radio system, a system allowing short-distance person-to-many persons bidirectional voice communication among individuals, using two way radios operating on ...

PMR446 PMR446 (Private Mobile Radio, 446 MHz) is a licence exempt service in the UHF radio frequency band and is available for business and personal use in most countries throughout the European Union. PMR446 is typically used for small-site, sa ...

and

Family Radio Service The Family Radio Service (FRS) is an improved walkie-talkie radio system authorized in the United States since 1996. This personal radio service uses channelized frequencies around 462 and 467 MHz in the ultra high frequency (UHF) band. I ...

References

{{Reflist Internet protocols Public safety communications Radio communications Interoperable communications Network appliances Radio hobbies Amateur radio software for Windows Amateur radio software for Linux

Implementations

See also

References