Hinternet
Encyclopedia
High-speed multimedia radio (HSMM), colloquially referred to as the hinternet, is the implementation of wireless data networks over amateur radio
frequencies using commercial off-the-shelf
(COTS) hardware such as 802.11 access points
and D-Star
equipment. Licensed amateur radio operator
s may use amplifier
s and specialized antennas
to increase the power
and coverage of the 802.11 signal.
The name hinternet comes from a combination of the words ham and Internet and can be used to refer to any high speed data network over amateur radio, not just 802.11 networks.
, 2.4 GHz (13 cm), 3.4 GHz (9 cm), and 5.8 GHz (5 cm) amateur radio bands under the U.S. Federal Communications Commission
(FCC) Part 97 rules (amateur radio service) instead of the Part 15 rules (unlicensed). This enables amateur operators to legally use higher output power for wireless devices and allows for longer-range communications. Such communications can be used to assist in emergency communications and disaster relief operations and in everyday amateur radio
communications.
, the Web (HTTP), file transfer (FTP), and forum
s. The only differences being that on the hinternet such services are community instead of commercially implemented and the "hinternet" is mostly wireless. The hinternet can even be connected to the Internet and used for "Web surfing", although because of the FCC regulations on permitted content, this is rarely done. Using high gain antennas and amplifiers, reliable long-distance wireless links over many miles are possible and only limited by the radio horizon.
. Note that the 5 cm amateur band extends from 5650 to 5925 MHz, so that there are many frequencies outside the Part 15 ISM/UNII block used for 802.11a. Many commercial grade 802.11a access points can also operate in between the normal channels by using 5 MHz channel spacing instead of the standard 20 MHz channel spacing. 802.11a channels 132, 136 and 140 are only available for unlicensed use in ETSI regions.
The following images show the overlapping relationship of the Part 15 unlicensed bands and the Part 97 licensed bands. The images are not to scale.
2.4 GHz 802.11b/g
5.8 GHz 802.11a
. This custom firmware is freely available on the Internet from projects such as DD-WRT
and OpenWrt
. The most popular piece of hardware that is modified is the Linksys WRT54GL because of the widespread availability of both the hardware and third party firmware.
Amateur radio
Amateur radio is the use of designated radio frequency spectrum for purposes of private recreation, non-commercial exchange of messages, wireless experimentation, self-training, and emergency communication...
frequencies using commercial off-the-shelf
Commercial off-the-shelf
In the United States, Commercially available Off-The-Shelf is a Federal Acquisition Regulation term defining a nondevelopmental item of supply that is both commercial and sold in substantial quantities in the commercial marketplace, and that can be procured or utilized under government contract...
(COTS) hardware such as 802.11 access points
Wireless access point
In computer networking, a wireless access point is a device that allows wireless devices to connect to a wired network using Wi-Fi, Bluetooth or related standards...
and D-Star
D-STAR
D-STAR is a digital voice and data protocol specification developed as the result of research by the Japan Amateur Radio League to investigate digital technologies for amateur radio...
equipment. Licensed amateur radio operator
Amateur radio operator
An amateur radio operator is an individual who typically uses equipment at an amateur radio station to engage in two-way personal communications with other similar individuals on radio frequencies assigned to the amateur radio service. Amateur radio operators have been granted an amateur radio...
s may use amplifier
Amplifier
Generally, an amplifier or simply amp, is a device for increasing the power of a signal.In popular use, the term usually describes an electronic amplifier, in which the input "signal" is usually a voltage or a current. In audio applications, amplifiers drive the loudspeakers used in PA systems to...
s and specialized antennas
Antenna (radio)
An antenna is an electrical device which converts electric currents into radio waves, and vice versa. It is usually used with a radio transmitter or radio receiver...
to increase the power
Transmitter power output
In radio transmission, transmitter power output is the actual amount of power of radio frequency energy that a transmitter produces at its output....
and coverage of the 802.11 signal.
The name hinternet comes from a combination of the words ham and Internet and can be used to refer to any high speed data network over amateur radio, not just 802.11 networks.
Basics
The idea behind this implementation is to use the 900 MHz (33 cm)33 centimeters
The 33-centimeter or 900 MHz band is a portion of the UHF radio spectrum internationally allocated to amateur radio on a secondary basis. It ranges from 902 to 928 MHz and is unique to ITU Region 2. It is primarily used for very local communications as opposed to bands lower in frequency...
, 2.4 GHz (13 cm), 3.4 GHz (9 cm), and 5.8 GHz (5 cm) amateur radio bands under the U.S. Federal Communications Commission
Federal Communications Commission
The Federal Communications Commission is an independent agency of the United States government, created, Congressional statute , and with the majority of its commissioners appointed by the current President. The FCC works towards six goals in the areas of broadband, competition, the spectrum, the...
(FCC) Part 97 rules (amateur radio service) instead of the Part 15 rules (unlicensed). This enables amateur operators to legally use higher output power for wireless devices and allows for longer-range communications. Such communications can be used to assist in emergency communications and disaster relief operations and in everyday amateur radio
Amateur radio
Amateur radio is the use of designated radio frequency spectrum for purposes of private recreation, non-commercial exchange of messages, wireless experimentation, self-training, and emergency communication...
communications.
What can it do?
The "hinternet" can support most of the traffic that the Internet currently does, including video chat, voice, instant messagingInstant messaging
Instant Messaging is a form of real-time direct text-based chatting communication in push mode between two or more people using personal computers or other devices, along with shared clients. The user's text is conveyed over a network, such as the Internet...
, the Web (HTTP), file transfer (FTP), and forum
Internet forum
An Internet forum, or message board, is an online discussion site where people can hold conversations in the form of posted messages. They differ from chat rooms in that messages are at least temporarily archived...
s. The only differences being that on the hinternet such services are community instead of commercially implemented and the "hinternet" is mostly wireless. The hinternet can even be connected to the Internet and used for "Web surfing", although because of the FCC regulations on permitted content, this is rarely done. Using high gain antennas and amplifiers, reliable long-distance wireless links over many miles are possible and only limited by the radio horizon.
Frequencies and channels
The following is a list of the 802.11 channels that overlap into an amateur radio band under the FCC in the United StatesUnited States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
. Note that the 5 cm amateur band extends from 5650 to 5925 MHz, so that there are many frequencies outside the Part 15 ISM/UNII block used for 802.11a. Many commercial grade 802.11a access points can also operate in between the normal channels by using 5 MHz channel spacing instead of the standard 20 MHz channel spacing. 802.11a channels 132, 136 and 140 are only available for unlicensed use in ETSI regions.
EWLINE
|
EWLINE
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The following images show the overlapping relationship of the Part 15 unlicensed bands and the Part 97 licensed bands. The images are not to scale.
2.4 GHz 802.11b/g
5.8 GHz 802.11a
- Acronyms Used: (AMSATAMSATAMSAT is a name for amateur radio satellite organizations worldwide, but in particular the Radio Amateur Satellite Corporation with headquarters at Silver Spring, Maryland, near Washington DC. AMSAT organizations design, build, arrange launches for, and then operate satellites carrying amateur...
) (ISMISM bandThe industrial, scientific and medical radio bands are radio bands reserved internationally for the use of radio frequency energy for industrial, scientific and medical purposes other than communications....
) (RadarRadarRadar is an object-detection system which uses radio waves to determine the range, altitude, direction, or speed of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. The radar dish or antenna transmits pulses of radio...
)
802.11a
- The 802.11a amateur radio band consists of twelve non-overlapping channels in the 5.650–5.925 GHz (5 cm) band. The 802.11a standard uses OFDM or "Orthogonal Frequency Division Multiplexing" to transmit data and therefore is not classified as spread-spectrum. Because of this 802.11a hardware is not subject to the power rules in FCC Part 97 § 97.311 and the maximum allowable output power is 1500 wattWattThe watt is a derived unit of power in the International System of Units , named after the Scottish engineer James Watt . The unit, defined as one joule per second, measures the rate of energy conversion.-Definition:...
s (W) PEPPeak envelope powerPeak envelope power is the average power supplied to the antenna transmission line by a transmitter during one radio frequency cycle at the crest of the modulation envelope, under normal operating conditions. The United States Federal Communications Commission uses PEP to set maximum power...
.
802.11b
- The 802.11b amateur radio band consists of eight overlapping channels in the 2.390–2.450 GHz (13 cm) band. The 802.11b specification uses Direct Sequence Spread Spectrum (DSSS) to transmit data and is subject to the rules of FCC Part 97 § 97.311. Therefore the maximum allowable power output is 10 W PEPPeak envelope powerPeak envelope power is the average power supplied to the antenna transmission line by a transmitter during one radio frequency cycle at the crest of the modulation envelope, under normal operating conditions. The United States Federal Communications Commission uses PEP to set maximum power...
.
802.11g
- The 802.11g amateur radio band consists of eight overlapping channels in the 2.4 GHz (13 cm) band. The 802.11g standard uses OFDM or "Orthogonal Frequency Division Multiplexing" to transmit data and therefore is not classified as spread-spectrum. Because of this 802.11g hardware is not subject to the power rules in FCC Part 97 § 97.311 and the maximum allowable output power is 1500 W PEPPeak envelope powerPeak envelope power is the average power supplied to the antenna transmission line by a transmitter during one radio frequency cycle at the crest of the modulation envelope, under normal operating conditions. The United States Federal Communications Commission uses PEP to set maximum power...
.
802.11a
- The 5 cm band is sharedFrequency sharingIn telecommunication, frequency sharing is the assignment to or use of the same radio frequency by two or more stations that are separated geographically or that use the frequency at different times....
with the fixed-satellite service in ITUItuItu is an old and historic municipality in the state of São Paulo in Brazil. The population in 2009 was 157,384 and the area is 641.68 km². The elevation is 583 m. This place name comes from the Tupi language, meaning big waterfall. Itu is linked with the highway numbered the SP-75 and are flowed...
Region 1ITU regionThe International Telecommunication Union , in its International Radio Regulations, divides the world into three ITU regions for the purposes of managing the global radio spectrum...
, and the radiolocationRadiolocationRadiolocating is the process of finding the location of something through the use of radio waves. It generally refers to passive uses, particularly radar—as well as detecting buried cables, water mains, and other public utilities. It is similar to radionavigation, but radiolocation usually...
service. In ITU Region 2 (US) the primary user is military radiolocation, specifically naval radar. Amateur radio operators have secondary privileges to the Federal radiolocation service in the entire band and may not cause interference to these users. Amateur operators are allocated this band are in a co-secondary basis with ISMISM bandThe industrial, scientific and medical radio bands are radio bands reserved internationally for the use of radio frequency energy for industrial, scientific and medical purposes other than communications....
devices and space research. Amateur, space research, and ISM operators each have the "right to operate". Due to the lack of a high number of Part 15 users (compared to 2.4 GHz), the noise level tends to be lower in many parts of the US but can be quite congested in urban centers and on mountaintops.
802.11b/g
- The 13 cm band is shared with Part 15 users as well as the Federal radiolocation service, and ISM (industrial, scientific, medical) devices. Amateur radio operators have secondary privileges to the Federal radiolocation service in the entire band and may not cause interference to these users. Amateur radio operators have primary privileges to ISM devices from 2.390–2.417 GHz and secondary privileges from 2.417–2.450 GHz. Because of the high number of Part 15 users, the noise level in this band tends to be rather high.
Identification
- As with any amateur radio mode stations must identify at least once every 10 minutes. One acceptable method for doing so is to transmit one’s call sign inside an ICMP echo request (commonly known as a pingPingPing is a computer network administration utility used to test the reachability of a host on an Internet Protocol network and to measure the round-trip time for messages sent from the originating host to a destination computer...
). If the access pointWireless access pointIn computer networking, a wireless access point is a device that allows wireless devices to connect to a wired network using Wi-Fi, Bluetooth or related standards...
is set to "master" then the user’s call sign may be set as the "SSIDService set identifierA service set is all the devices associated with a local or enterprise IEEE 802.11 wireless local area network .-Service set identifier :...
" and therefore will be transmitted at regular intervals.
- It is also possible to use a DDNS "push" request to automatically send an amateur callsign in plain text (ASCIIASCIIThe American Standard Code for Information Interchange is a character-encoding scheme based on the ordering of the English alphabet. ASCII codes represent text in computers, communications equipment, and other devices that use text...
) every 10 minutes. This requires that a computers hostnameHostnameA hostname is a label that is assigned to a device connected to a computer network and that is used to identify the device in various forms of electronic communication such as the World Wide Web, e-mail or Usenet...
be set to the callsign of the amateur operator and that the DHCP servers lease time be set to less than or equal to 10 minutes. With this method implemented the computer will send a DNS "push" request that includes the local computers hostname every time the DHCP lease is renewed. This method is supported by all modern operating systems including but not limited to WindowsMicrosoft WindowsMicrosoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...
, Mac OS XMac OS XMac OS X is a series of Unix-based operating systems and graphical user interfaces developed, marketed, and sold by Apple Inc. Since 2002, has been included with all new Macintosh computer systems...
, BSD, and LinuxLinuxLinux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
.
- 802.11 hardware may transmit and receive the entire time it is powered on even if the user is not sending data.
Security
- Because the meaning of amateur transmissions may not be obscured, security measures that are implemented must be published. This does not necessarily restrict authentication or login schemes, but it does restrict fully encrypted communications. This leaves the communications vulnerable to various attacks once the authentication has been completed. This makes it very difficult to keep unauthorized users from accessing HSMM networks, although casual eavesdroppers can effectively be deterred. Current schemes include using MAC addressMAC addressA Media Access Control address is a unique identifier assigned to network interfaces for communications on the physical network segment. MAC addresses are used for numerous network technologies and most IEEE 802 network technologies, including Ethernet...
filtering, WEPWired Equivalent PrivacyWired Equivalent Privacy is a weak security algorithm for IEEE 802.11 wireless networks. Introduced as part of the original 802.11 standard ratified in September 1999, its intention was to provide data confidentiality comparable to that of a traditional wired network...
and WPAWi-Fi Protected AccessWi-Fi Protected Access and Wi-Fi Protected Access II are two security protocols and security certification programs developed by the Wi-Fi Alliance to secure wireless computer networks...
/WPA2. MAC address filtering and WEP are all hackable by using freely available software from the Internet, making them the less secure options. Per FCC rules the encryption keys themselves must be published in a publicly accessible place if using WEP, WPA/WPA2 or any other encryption, thereby undermining the security of their implementation. Such measures however are effective against casual or accidental wireless intrusions.
- Using professional or modified hardware it is possible to operate on 802.11a channels that are outside the FCC authorized Part 15 bands but still inside the 5.8 GHz (5 cm) or 2.4 GHz (13cm) amateur radio bands. TransverterTransverterA transverter is a radio frequency device that consists of an upconverter and a downconverter in one unit. Transverters are used in conjunction with transceivers to change the range of frequencies over which the transceiver can communicate....
s or "frequency converters" can also be used to move HSMM 802.11b/g operations from the 2.4 GHz (13 cm) band to the 3.4 GHz (9 cm) amateur radio band. Such relocation provides a measure of security by operating outside the channels available to unlicensed (Part 15) 802.11 devices.
Custom frequencies
- Using professional grade commercial hardware or modified consumer grade hardware it is possible to operate 802.11 on channels that are outside of the normal FCC allocated frequencies for unlicensed users but still inside an amateur radio band. Some of these frequencies are inside the 2.4 GHz (13 cm), 3.4 GHz (9 cm) and the 5.8 GHz (5 cm) amateur radio bands, thereby providing better security and interference characteristics to amateur radio operators. While using amateur-only frequencies all but alleviates the security concerns of using 802.11, the relative high cost of such devices is a large deterrent to their widespread deployment.
420 MHz
- XAGYL Communications, is a Canadian Distributor of Ultra High-Speed, Long Range Wireless equipment. In 2009 they partnered with Doodle Labs, a privately held manufacturing company with headquarters in Singapore to design and manufacture a new line of long range Wireless Data Transceiver devices.
- The Doodle Labs DL435-30 or XAGYL Communications XC450M2, is a mini-PCI adapter based on the Atheros wireless chipset. In theory, the Atheros chipset's ability to use 5 MHz transmission bandwidths could allow part 97 operation on the 420-430 MHz ATV sub-band.
- 420-430 MHz operation is not allowed near the Canadian border.
900 MHz
- Transverters as well as using older 802.11 hardware such as the original NRC WaveLan or FHSS modems made by Aerocomm and FreeWave make it possible to operate on this band. Beware that noise floors on this band are usually very high in the larger cities.
2.4 GHz custom frequencies
- Using professional grade hardware or modified consumer grade hardware it is possible to operate on 802.11b/g hardware on channels that are effectively "0" at 2.407 GHz and "−1" at 2.402 GHz. Using these channels allows amateur operators to move away from unlicensed Part 15 operators but may interfere with AMSATAMSATAMSAT is a name for amateur radio satellite organizations worldwide, but in particular the Radio Amateur Satellite Corporation with headquarters at Silver Spring, Maryland, near Washington DC. AMSAT organizations design, build, arrange launches for, and then operate satellites carrying amateur...
satellite downlinks near 2.400 GHz and 2.401 GHz.
3.4 GHz
- Frequency conversion involves the use of transverterTransverterA transverter is a radio frequency device that consists of an upconverter and a downconverter in one unit. Transverters are used in conjunction with transceivers to change the range of frequencies over which the transceiver can communicate....
s that convert the operating frequency of the 802.11b/g device from 2.4 GHz to another band entirely. Transverter is a technical term and is rarely used to describe these products which are more commonly known as frequency converters, up/down converters, and just converters. Commercially-available converters can convert a 2.4 GHz 802.11b/g signal to the 3.4 GHz (9 cm) band which is not authorized for unlicensed Part 15 users.
- Ubiquiti Networks has two radios based on Atheros chipsets with transverters onboard for this band. The XtremeRange3 is a mini-PCI Adapter for 3.5GHz. And the 3 GHz Nanostation. This version is in a molded weatherproof case with 13 dBi antenna, dual polarization, plus external SMA antenna connector.
5.8 GHz custom frequencies
- Using professional grade hardware or modified consumer grade hardware it is possible to operate on 802.11a channels 116–140 (5.57–5.71 GHz) and channels above 165 (> 5.835 GHz). These frequencies are outside of the FCC allocated Part 15 unlicensed band, but still inside of the 5.8 GHz (5 cm) amateur radio band. Modifying consumer hardware to operate on these expanded channels often involves installing after-market firmwareFirmwareIn electronic systems and computing, firmware is a term often used to denote the fixed, usually rather small, programs and/or data structures that internally control various electronic devices...
and/or changing the "country code" setting of the wireless card. When buying professional grade hardware, many companies will authorize the use of these expanded frequencies for a small additional fee.
Custom firmware
One popular way to access amateur only frequencies is to modify an off-the-shelf access point with custom firmwareFirmware
In electronic systems and computing, firmware is a term often used to denote the fixed, usually rather small, programs and/or data structures that internally control various electronic devices...
. This custom firmware is freely available on the Internet from projects such as DD-WRT
DD-WRT
DD-WRT is a Linux-based firmware for several wireless routers, most notably the Linksys WRT54G . Like other similar projects, DD-WRT is third-party firmware designed to replace the firmware that ships pre-installed on many commercial routers...
and OpenWrt
OpenWrt
OpenWrt is a Linux distribution primarily targeted at routing on embedded devices. It comprises a set of about 2000 software packages, installed and uninstalled via the opkg package management system. OpenWrt can be configured using the command-line interface of BusyBox ash, or the web interface...
. The most popular piece of hardware that is modified is the Linksys WRT54GL because of the widespread availability of both the hardware and third party firmware.
See also
- Amateur radio emergency communicationsAmateur radio emergency communicationsIn times of crisis and natural disasters, amateur radio is often used as a means of emergency communication when wireline, cell phones and other conventional means of communications fail....
- Amateur radio frequency allocationsAmateur radio frequency allocationsAmateur radio frequency allocation is done by national telecommunications authorities. Globally, the International Telecommunication Union oversees how much radio spectrum is set aside for amateur radio transmissions...
- AMPRNetAMPRNetThe AMPRNet is a name used by amateur radio operators for computer networks connected over amateur radio. Other names for the network include IPv4 Network 44/8 and Network 44...
- DD-WRTDD-WRTDD-WRT is a Linux-based firmware for several wireless routers, most notably the Linksys WRT54G . Like other similar projects, DD-WRT is third-party firmware designed to replace the firmware that ships pre-installed on many commercial routers...
- List of hsmm nodes
- Metropolitan Area NetworkMetropolitan area networkA metropolitan area network is a computer network that usually spans a city or a large campus. A MAN usually interconnects a number of local area networks using a high-capacity backbone technology, such as fiber-optical links, and provides up-link services to wide area networks and the...
- Orthogonal frequency-division multiplexingOrthogonal frequency-division multiplexingOrthogonal frequency-division multiplexing is a method of encoding digital data on multiple carrier frequencies. OFDM has developed into a popular scheme for wideband digital communication, whether wireless or over copper wires, used in applications such as digital television and audio...
- Packet RadioPacket radioPacket radio is a form of packet switching technology used to transmit digital data via radio or wireless communications links. It uses the same concepts of data transmission via Datagram that are fundamental to communications via the Internet, as opposed to the older techniques used by dedicated...
- Spread spectrumSpread spectrumSpread-spectrum techniques are methods by which a signal generated in a particular bandwidth is deliberately spread in the frequency domain, resulting in a signal with a wider bandwidth...
- Tomato FirmwareTomato FirmwareTomato Firmware is a partially free HyperWRT-based, Linux core firmware distribution for a range of Broadcom chipset based wireless routers, most notably the older-model Linksys WRT54G , Buffalo AirStation, Asus Routers and Netgear's WNR3500L...
- Ultra wideband
- Wireless Distribution SystemWireless Distribution SystemA wireless distribution system is a system enabling the wireless interconnection of access points in an IEEE 802.11 network. It allows a wireless network to be expanded using multiple access points without the traditional requirement for a wired backbone to link them...
- Wireless LANWireless LANA wireless local area network links two or more devices using some wireless distribution method , and usually providing a connection through an access point to the wider internet. This gives users the mobility to move around within a local coverage area and still be connected to the network...
External links
- D-Star System
- FCC Part 97 Rules
- FCC Part 15 Rules
- FCC rejection of OFDM as Spread Spectrum
- Using Part 15 Wireless Ethernet Devices For Amateur Radio
- 5.0 GHz (802.11a/h) Channels and Frequencies
- N5OOM’s HSMM Projects: Web page from N5OOM detailing several projects and implementations of HSMM.
- HSMM-MESH.ORG Wireless Mesh: Austin, Texas Travis County ARES/ARCHES HSMM MESH
- HSMM Wiki