Business 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 networking or, more commonly, as an alternative method of cable television programming reception. MMDS is used in The United States, Canada, Mexico, Dominican Republic, Iceland, Ireland, Russia, Slovenia, Brazil, Barbados, Australia, Nigeria, Pakistan, Sri Lanka, Thailand, Uruguay, India, Belarus, Lebanon and Cambodia. It is most commonly used in sparsely populated rural areas, where laying cables is not economically viable, although some companies may also offer MMDS services in urban areas.
MMDS microwave dish
Technology
The BRS band uses microwave frequencies from 2 GHz to 3 GHz in range. Reception of BRS-delivered television signals is done with a special rooftop microwave antenna and a set-top box for the television receiving the signals. The antenna usually has an integrated down-converter to transmit the signals at frequencies compatible with terrestrial TV tuners down on the coax (much like on satellite dishes where the signals are converted down to frequencies more compatible with standard TV coaxial cabling), some larger antennas use an external down-converter. The receiver box is very similar in appearance to an analogue cable television receiver box.
The MMDS band was separated into eleven "channels" which are auctioned off like other bands. The idea was that entities could own several channels and multiplex several television and radio channels onto each channel using digital technology. Each "channel" was capable of 10 Mbit/s, exclusive of any forward error correction technology that is required for this type of technology.
MMDS and DOCSIS+
Local Multipoint Distribution Service (LMDS) and BRS have adapted the DOCSIS (Data Over Cable Service Interface Specification) from the cable modem 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 wireless modem and the WMTS (Wireless Modem Termination System) located in the base station of the providers network using Triple DES.
DOCSIS+ reduces theft-of-service vulnerabilities under BRS by requiring that the WMTS enforce encryption, and by employing an authenticated client/server key-management protocol in which the WMTS controls distribution of keying 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 digital certificates, RSA public key encryption, 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 WiMAX 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 TV (based in Lima, OH), Eagle Vision (based in Kirksville, MO), and several other companies offer MMDS based wireless cable television, internet access, and IP based telephone services. With T-Mobile USA acquiring the MMDS band in most areas of the country, the future of this kind of service in the USA is in doubt.
In certain areas, BRS is being deployed for use as wireless high-speed internet access, 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.
In Ireland, Chorus and NTL Ireland both offer separate MMDS services in many regions. Chorus still broadcast 11-channel analogue MMDS in some areas, though with their recent acquisition by Liberty Global Europe (along with NTL Ireland), it is quite likely their systems will be merged and after suitable upgrading the analogue services will be dropped and be replaced by the DVB-C systems used elsewhere.
In Iceland, 365 Broadcast Media offers digital MMDS television services using DVB-T technology alongside a few analogue channels.
The BRS band uses microwave frequencies from 2 GHz to 3 GHz in range. Reception of BRS-delivered television signals is done with a special rooftop microwave antenna and a set-top box for the television receiving the signals. The antenna usually has an integrated down-converter to transmit the signals at frequencies compatible with terrestrial TV tuners down on the coax (much like on satellite dishes where the signals are converted down to frequencies more compatible with standard TV coaxial cabling), some larger antennas use an external down-converter. The receiver box is very similar in appearance to an analogue cable television receiver box.
The MMDS band was separated into eleven "channels" which are auctioned off like other bands. The idea was that entities could own several channels and multiplex several television and radio channels onto each channel using digital technology. Each "channel" was capable of 10 Mbit/s, exclusive of any forward error correction technology that is required for this type of technology.
MMDS and DOCSIS+
Local Multipoint Distribution Service (LMDS) and BRS have adapted the DOCSIS (Data Over Cable Service Interface Specification) from the cable modem 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 wireless modem and the WMTS (Wireless Modem Termination System) located in the base station of the providers network using Triple DES.
DOCSIS+ reduces theft-of-service vulnerabilities under BRS by requiring that the WMTS enforce encryption, and by employing an authenticated client/server key-management protocol in which the WMTS controls distribution of keying 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 digital certificates, RSA public key encryption, 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 WiMAX 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 TV (based in Lima, OH), Eagle Vision (based in Kirksville, MO), and several other companies offer MMDS based wireless cable television, internet access, and IP based telephone services. With T-Mobile USA acquiring the MMDS band in most areas of the country, the future of this kind of service in the USA is in doubt.
In certain areas, BRS is being deployed for use as wireless high-speed internet access, 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.
In Ireland, Chorus and NTL Ireland both offer separate MMDS services in many regions. Chorus still broadcast 11-channel analogue MMDS in some areas, though with their recent acquisition by Liberty Global Europe (along with NTL Ireland), it is quite likely their systems will be merged and after suitable upgrading the analogue services will be dropped and be replaced by the DVB-C systems used elsewhere.
In Iceland, 365 Broadcast Media offers digital MMDS television services using DVB-T technology alongside a few analogue channels.
Hernández Caballero Indiana
Asignatura: CRF
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