Multichannel Multipoint Distribution Service
Encyclopedia
Broadband Radio Service (BRS) formerly known as Multichannel Multipoint Distribution Service (MMDS), also known as Wireless Cable, is a wireless telecommunications technology, used for general-purpose broadband
Broadband
The term broadband refers to a telecommunications signal or device of greater bandwidth, in some sense, than another standard or usual signal or device . Different criteria for "broad" have been applied in different contexts and at different times...

 networking
Computer network
A computer network, often simply referred to as a network, is a collection of hardware components and computers interconnected by communication channels that allow sharing of resources and information....

 or, more commonly, as an alternative method of cable television
Cable television
Cable television is a system of providing television programs to consumers via radio frequency signals transmitted to televisions through coaxial cables or digital light pulses through fixed optical fibers located on the subscriber's property, much like the over-the-air method used in traditional...

 programming reception. MMDS is used in The United States, Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

, Mexico
Mexico
The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...

, Dominican Republic
Dominican Republic
The Dominican Republic is a nation on the island of La Hispaniola, part of the Greater Antilles archipelago in the Caribbean region. The western third of the island is occupied by the nation of Haiti, making Hispaniola one of two Caribbean islands that are shared by two countries...

, Iceland
Iceland
Iceland , described as the Republic of Iceland, is a Nordic and European island country in the North Atlantic Ocean, on the Mid-Atlantic Ridge. Iceland also refers to the main island of the country, which contains almost all the population and almost all the land area. The country has a population...

, Ireland
Republic of Ireland
Ireland , described as the Republic of Ireland , is a sovereign state in Europe occupying approximately five-sixths of the island of the same name. Its capital is Dublin. Ireland, which had a population of 4.58 million in 2011, is a constitutional republic governed as a parliamentary democracy,...

, Ukraine
Ukraine
Ukraine is a country in Eastern Europe. It has an area of 603,628 km², making it the second largest contiguous country on the European continent, after Russia...

, Russia
Russia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...

, Slovakia
Slovakia
The Slovak Republic is a landlocked state in Central Europe. It has a population of over five million and an area of about . Slovakia is bordered by the Czech Republic and Austria to the west, Poland to the north, Ukraine to the east and Hungary to the south...

, Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...

, Barbados
Barbados
Barbados is an island country in the Lesser Antilles. It is in length and as much as in width, amounting to . It is situated in the western area of the North Atlantic and 100 kilometres east of the Windward Islands and the Caribbean Sea; therein, it is about east of the islands of Saint...

, Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

, Nigeria
Nigeria
Nigeria , officially the Federal Republic of Nigeria, is a federal constitutional republic comprising 36 states and its Federal Capital Territory, Abuja. The country is located in West Africa and shares land borders with the Republic of Benin in the west, Chad and Cameroon in the east, and Niger in...

, Pakistan
Pakistan
Pakistan , officially the Islamic Republic of Pakistan is a sovereign state in South Asia. It has a coastline along the Arabian Sea and the Gulf of Oman in the south and is bordered by Afghanistan and Iran in the west, India in the east and China in the far northeast. In the north, Tajikistan...

, Panama
Panama
Panama , officially the Republic of Panama , is the southernmost country of Central America. Situated on the isthmus connecting North and South America, it is bordered by Costa Rica to the northwest, Colombia to the southeast, the Caribbean Sea to the north and the Pacific Ocean to the south. The...

, Sri Lanka
Sri Lanka
Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka is a country off the southern coast of the Indian subcontinent. Known until 1972 as Ceylon , Sri Lanka is an island surrounded by the Indian Ocean, the Gulf of Mannar and the Palk Strait, and lies in the vicinity of India and the...

, Thailand
Thailand
Thailand , officially the Kingdom of Thailand , formerly known as Siam , is a country located at the centre of the Indochina peninsula and Southeast Asia. It is bordered to the north by Burma and Laos, to the east by Laos and Cambodia, to the south by the Gulf of Thailand and Malaysia, and to the...

, Uruguay
Uruguay
Uruguay ,officially the Oriental Republic of Uruguay,sometimes the Eastern Republic of Uruguay; ) is a country in the southeastern part of South America. It is home to some 3.5 million people, of whom 1.8 million live in the capital Montevideo and its metropolitan area...

, India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...

, Belarus
Belarus
Belarus , officially the Republic of Belarus, is a landlocked country in Eastern Europe, bordered clockwise by Russia to the northeast, Ukraine to the south, Poland to the west, and Lithuania and Latvia to the northwest. Its capital is Minsk; other major cities include Brest, Grodno , Gomel ,...

, Lebanon
Lebanon
Lebanon , officially the Republic of LebanonRepublic of Lebanon is the most common term used by Lebanese government agencies. The term Lebanese Republic, a literal translation of the official Arabic and French names that is not used in today's world. Arabic is the most common language spoken among...

, Cambodia
Cambodia
Cambodia , officially known as the Kingdom of Cambodia, is a country located in the southern portion of the Indochina Peninsula in Southeast Asia...

 and Kazakhstan
Kazakhstan
Kazakhstan , officially the Republic of Kazakhstan, is a transcontinental country in Central Asia and Eastern Europe. Ranked as the ninth largest country in the world, it is also the world's largest landlocked country; its territory of is greater than Western Europe...

. It is most commonly used in sparsely populated rural
Rural
Rural areas or the country or countryside are areas that are not urbanized, though when large areas are described, country towns and smaller cities will be included. They have a low population density, and typically much of the land is devoted to agriculture...

 areas, where laying cables is not economically viable, although some companies may also offer MMDS services in urban
Urban area
An urban area is characterized by higher population density and vast human features in comparison to areas surrounding it. Urban areas may be cities, towns or conurbations, but the term is not commonly extended to rural settlements such as villages and hamlets.Urban areas are created and further...

 areas.

Technology

The BRS band uses microwave
Microwave
Microwaves, a subset of radio waves, have wavelengths ranging from as long as one meter to as short as one millimeter, or equivalently, with frequencies between 300 MHz and 300 GHz. This broad definition includes both UHF and EHF , and various sources use different boundaries...

 frequencies
Electromagnetic spectrum
The electromagnetic spectrum is the range of all possible frequencies of electromagnetic radiation. The "electromagnetic spectrum" of an object is the characteristic distribution of electromagnetic radiation emitted or absorbed by that particular object....

 at 2.1 GHz and from 2.5 GHz to 2.7 GHz
GHZ
GHZ or GHz may refer to:# Gigahertz .# Greenberger-Horne-Zeilinger state — a quantum entanglement of three particles.# Galactic Habitable Zone — the region of a galaxy that is favorable to the formation of life....

. Reception of BRS-delivered television and data signals is done with a rooftop microwave antenna. The antenna is attached to a down-converter or transceiver to receive and transmit the microwave signal and convert them to frequencies compatible with standard TV tuners (much like on satellite dish
Satellite dish
A satellite dish is a dish-shaped type of parabolic antenna designed to receive microwaves from communications satellites, which transmit data transmissions or broadcasts, such as satellite television.-Principle of operation:...

es where the signals are converted down to frequencies more compatible with standard TV coaxial cabling
Coaxial cable
Coaxial cable, or coax, has an inner conductor surrounded by a flexible, tubular insulating layer, surrounded by a tubular conducting shield. The term coaxial comes from the inner conductor and the outer shield sharing the same geometric axis...

), some antennas use an integrated down-converter
Digital down converter
In digital signal processing, a digital down-converter converts a digitized real signal centered at an intermediate frequency to a basebanded complex signal centered at zero frequency...

 or transceiver. Digital TV channels can then be decoded with a standard cable set-top box
Set-top box
A set-top box or set-top unit is an information appliance device that generally contains a tuner and connects to a television set and an external source of signal, turning the signal into content which is then displayed on the television screen or other display device.-History:Before the...

 or directly for TVs with integrated digital tuners. Internet data can be received with a standard DOCSIS Cable Modem connected to the same antenna and transceiver.

The MMDS band was separated into 33 6 MHz "channels" which were auctioned off like other bands. The concept was to allow entities to own several channels and multiplex
Multiplexing
The multiplexed signal is transmitted over a communication channel, which may be a physical transmission medium. The multiplexing divides the capacity of the low-level communication channel into several higher-level logical channels, one for each message signal or data stream to be transferred...

 several television, radio, and later Internet data onto each channel using digital technology. Just like with Digital Cable channels, each channel is capable of 30.34 Mbit/s with 64QAM modulation, and 42.88 Mbit/s with 256QAM modulation. Due to forward error correction
Forward error correction
In telecommunication, information theory, and coding theory, forward error correction or channel coding is a technique used for controlling errors in data transmission over unreliable or noisy communication channels....

 and other overhead, actual throughput is around 27 Mbit/s for 64QAM and 38 Mbit/s for 256QAM.

The newer BRS Band Plan makes changes to channel size and licensing in order to accommodate new WIMAX TDD fixed and mobile equipment.

MMDS and DOCSIS+

Local Multipoint Distribution Service
Local Multipoint Distribution Service
LMDS is a broadband wireless access technology originally designed for digital television transmission . It was conceived as a fixed wireless, point-to-multipoint technology for utilization in the last mile....

 (LMDS) and BRS have adapted the DOCSIS
DOCSIS
Data Over Cable Service Interface Specification is an international telecommunications standard that permits the addition of high-speed data transfer to an existing cable TV system...

 (Data Over Cable Service Interface Specification) from the cable modem
Cable modem
A cable modem is a type of network bridge and modem that provides bi-directional data communication via radio frequency channels on a HFC and RFoG infrastructure. Cable modems are primarily used to deliver broadband Internet access in the form of cable Internet, taking advantage of the high...

 world. The version of DOCSIS modified for wireless broadband is known as DOCSIS+.

Data-transport security is accomplished under BRS by encrypting traffic flows between the broadband
Broadband
The term broadband refers to a telecommunications signal or device of greater bandwidth, in some sense, than another standard or usual signal or device . Different criteria for "broad" have been applied in different contexts and at different times...

 wireless modem
Wireless modem
A wireless modem is a type of modulator-demodulator which connects to a wireless network instead of using telephone or cable television lines...

 and the WMTS (Wireless Modem Termination System) located in the base station
Base station
The term base station can be used in the context of land surveying and wireless communications.- Land surveying :In the context of external land surveying, a base station is a GPS receiver at an accurately-known fixed location which is used to derive correction information for nearby portable GPS...

 of the providers network using Triple DES
Triple DES
In cryptography, Triple DES is the common name for the Triple Data Encryption Algorithm block cipher, which applies the Data Encryption Standard cipher algorithm three times to each data block....

.

DOCSIS+ reduces theft-of-service vulnerabilities under BRS by requiring that the WMTS enforce encryption
Encryption
In cryptography, encryption is the process of transforming information using an algorithm to make it unreadable to anyone except those possessing special knowledge, usually referred to as a key. The result of the process is encrypted information...

, and by employing an authenticated client/server key-management protocol
Key (cryptography)
In cryptography, a key is a piece of information that determines the functional output of a cryptographic algorithm or cipher. Without a key, the algorithm would produce no useful result. In encryption, a key specifies the particular transformation of plaintext into ciphertext, or vice versa...

 in which the WMTS controls distribution of keying
Cryptographic protocol
A security protocol is an abstract or concrete protocol that performs a security-related function and applies cryptographic methods.A protocol describes how the algorithms should be used...

 material to broadband wireless modems.

LMDS and BRS wireless modems utilize the DOCSIS+ key-management protocol to obtain authorization and traffic encryption material from a WMTS, and to support periodic reauthorization and key refresh. The key-management protocol uses X.509
X.509
In cryptography, X.509 is an ITU-T standard for a public key infrastructure and Privilege Management Infrastructure . X.509 specifies, amongst other things, standard formats for public key certificates, certificate revocation lists, attribute certificates, and a certification path validation...

 digital certificates, RSA public key encryption
Public-key cryptography
Public-key cryptography refers to a cryptographic system requiring two separate keys, one to lock or encrypt the plaintext, and one to unlock or decrypt the cyphertext. Neither key will do both functions. One of these keys is published or public and the other is kept private...

, and Triple DES encryption to secure key exchanges between the wireless modem and the WMTS.

MMDS provided significantly greater range than LMDS.

MMDS may be obsoleted by the newer 802.16
IEEE 802.16
IEEE 802.16 is a series of Wireless Broadband standards authored by the Institute of Electrical and Electronics Engineers . The IEEE Standards Board in established a working group in 1999 to develop standards for broadband Wireless Metropolitan Area Networks...

 WiMAX
WiMAX
WiMAX is a communication technology for wirelessly delivering high-speed Internet service to large geographical areas. The 2005 WiMAX revision provided bit rates up to 40 Mbit/s with the 2011 update up to 1 Gbit/s for fixed stations...

 standard approved since 2004.

MMDS was sometimes expanded to Multipoint Microwave Distribution System or Multi-channel Multi-point Distribution System. All three phrases refer to the same technology.

Current status

In the United States WATCH Communications (based in Lima, OH), Eagle Vision (based in Kirksville, MO), and several other companies offer MMDS based wireless cable television, internet access, and IP
Internet Protocol
The Internet Protocol is the principal communications protocol used for relaying datagrams across an internetwork using the Internet Protocol Suite...

 based telephone services.

With T-Mobile USA
T-Mobile USA
T-Mobile USA, Inc. is an American mobile-network operator, headquartered in Bellevue, Washington, that provides wireless voice, messaging and data services in the United States, Puerto Rico and the U.S. Virgin Islands. The company is the fourth-largest wireless carrier in the U.S. market with 33.73...

 acquiring the 2.1 GHz AWS band (old MDS band) in most areas of the country, which is used for the modem upstream in MMDS DOCSIS, the future of this kind of service in the USA is in doubt. However, new CPE equipment allows operators to use part of the main 2.5 - 2.7 GHz MMDS Spectrum for modem upstream, ensuring future operation in the United States. With newer WiMAX equipment available, some companies are looking to deploy mobile services instead of fixed services for future expansion.

In certain areas, BRS is being deployed for use as wireless high-speed internet access
Internet access
Many technologies and service plans for Internet access allow customers to connect to the Internet.Consumer use first became popular through dial-up connections in the 20th century....

, mostly in rural areas where other types of high-speed internet are either unavailable (such as cable or DSL) or prohibitively expensive (such as satellite internet). CommSPEED is a major vendor in the US market for BRS-based internet.http://www.commspeed.net/

AWI Networks (formerly Sky-View Technologies) operates a number of MMDS sites delivering High-Speed Internet, VoIP, and Digital TV services in Southern Utah USA. AWI has recently upgraded several sites to DOCSIS 3.0 hardware, delivering download speeds up to 100 Mbps. DOCSIS 3.0 has improved peak bandwidth, lower latency, and improved reliability over previous DOCSIS versions.

In the early days of MMDS it was known as Wireless Cable and was used in a variety of investment scams that still surface today. Frequent solicitations of Wireless Cable fraud schemes were often heard on talk radio shows like The Sonny Bloch Show in the mid 1990s.

In Ireland, UPC Ireland
UPC Ireland
UPC Ireland is Liberty Global Europe's telecommunications operation in Ireland. UPC Ireland is the largest digital cable television provider within the Republic of Ireland. As of September 2010 the company offers broadband internet, digital television and digital telephony to over 531,000 customers...

 (previously Chorus
Chorus Communications
Chorus Communications was a communications provider in Ireland, it offered internet, television and telephone services. It was owned by Liberty Global Europe, and ultimately controlled by John C. Malone's Liberty Media. It was based in Limerick, and owns the cable television and MMDS TV licences...

 and NTL Ireland
NTL Ireland
NTL Communications Limited was a cable television and Multichannel Multipoint Distribution Service company in the Republic of Ireland. As of 2005 it was owned by Liberty Global Europe , having been divested by NTL...

) offer MMDS TV services almost nationwide. The frequency band initially allocated was 2500 - 2690 MHz (the “2.6 GHz band”) consisting of 22-23 8 MHz analogue channels, digital TV was restricted to 2524 - 2668 MHz consisting of 18 8 MHz digital channels. Two digital TV standards are used DVB-T/MPEG-2 in the old Chorus franchise area (some areas still broadcast an 11-channel analogue MMDS TV service), and DVB-C/MPEG-2 in the old NTL franchise area. The existing licences expire in 2012 (ntl) and 2014 (Chorus) with an option extend to 2017/2019 following a review which commenced in May 2010.

In Iceland, since Nov 2006 Vodafone Iceland
Vodafone Iceland
Vodafone Iceland is an Icelandic telecommunications company and is part of the Icelandic IT company Teymi. Although the company carries the Vodafone brand and trademark, Vodafone Group owns no interest in the company, but rather franchises the brand and associated advertising styles to Teymi, the...

 runs Digital Ísland (Digital Iceland) - the broadcasting system for 365 (media corporation)
365 (media corporation)
365 is a mass media company in Iceland; a service company in the fields of television, radio broadcasting, news and publication of newspapers. The firm broadcasts over six TV stations, five radio stations and publishes one newspaper and one news website....

, (previously operated by 365 Broadcast Media). Digital Ísland offers digital MMDS television services using DVB-T
DVB-T
DVB-T is an abbreviation for Digital Video Broadcasting — Terrestrial; it is the DVB European-based consortium standard for the broadcast transmission of digital terrestrial television that was first published in 1997 and first broadcast in the UK in 1998...

 technology alongside a few analogue channels. The MMDS frequency range extends from 2500-2684 MHz for a total of 23 8 MHz channels, Of these, 21 are considered usable for broadcasting in Iceland. Analogue MMDS broadcasting began in 1993 moving to digital in 2004.

In Dominican Republic, Wind Telecom started operations using MMDS technology in 2008,at that time and ever since it became a pioneer taking advantage of such implementations.The company uses the DVB standard for its digital television transmissions.

See also

  • 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)
  • LMDS
    Local Multipoint Distribution Service
    LMDS is a broadband wireless access technology originally designed for digital television transmission . It was conceived as a fixed wireless, point-to-multipoint technology for utilization in the last mile....


External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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