In telecommunications, broadband is a broadband data transmission that carries many signals and traffic types. The medium may be coaxial cable, optical fiber, radio or twisted pair.
In the context of Internet access, broadband is used to mean any high-speed Internet access that is always on and faster than dial-up access through traditional analogue or ISDN PSTN services.
Video Broadband
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Different criteria for "broad" have been applied in different contexts and at different times. Its origin is in physics, acoustics, and radio system engineering, where it has been used with meanings similar to "broad band". Then, with the advent of digital telecommunications, the term is primarily used for transmission over multiple channels. While passband signals are also modulated to occupy higher frequencies (compared to baseband signals bound to the lowest end of the spectrum, see line coding), it still occupies one channel. The main difference is what is usually perceived as a broadband signal in this sense is a signal occupying multiple passband (non-masking, orthogonal), allowing for higher throughput over a single medium but with additional complexity in the transmitter circuit/receiver.
The term was popularized through the 1990s as a marketing term for faster Internet access than dialup access, the original Internet access technology, limited to a maximum bandwidth of 56 kbit/s. This meaning is only remotely related to its original technical meaning.
Maps Broadband
Broadband Technology
Telecommunications
In telecommunications, the method of broadband signaling is one that handles broad bands. "Broadband" is a relative term, understood in accordance with its context. The wider (or wider) channel bandwidth, the greater the data transport capacity, given the same channel quality.
On the radio, for example, very narrow bands will carry Morse code, wider bands will carry speeches, and wider bands will carry music without losing the high audio frequencies needed for realistic sound reproduction. These bands are often divided into channels or "frequency baskets" using the passband technique to allow multiplex frequency division rather than sending higher quality signals.
In data communications, a 56k modem will transmit data rates of 56 kilobits per second (kbit/s) over a 4-kilohertz-wide (narrowband or voiceband) phone line. In the late 1980s, the Broadband Integrated Service Digital Network (B-ISDN) used this term to refer to different bit levels, independent of physical modulation details. The various forms of digital subscriber line (DSL) services are broadband in the sense that digital information is transmitted over multiple channels. Each channel has a higher frequency than the baseband sound channel, so it can support regular phone service on a single pair of cables at the same time. However, when the same channel is converted into a non-loaded twisted-pair wire (no phone filter), it becomes hundreds of kilohertz (broadband) widths and can carry up to 100 megabits per second using very high bit-rate digital subscriber techniques line (VDSL or VHDSL).
Computer network
Many computer networks use simple line codes to transmit a single type of signal using a full medium bandwidth using their baseband (from zero to the highest frequency required). Most of the popular Ethernet family versions are named as the 1980s 10Base5 to show this. Networks that use cable modems on a standard cable television infrastructure are called broadband to show a wide range of frequencies that can include many data users as well as traditional television channels on the same cable. Broadband systems typically use different radio frequencies that are modulated by the data signal for each band.
The total bandwidth of the medium is greater than the bandwidth of any channel.
The 10BROAD36 broadband variant of Ethernet was standardized in 1985, but was not commercially successful.
The DOCSIS standard became available to consumers in the late 1990s, to provide Internet access to cable television housing customers. Things are further confused by the fact that the 10PASS-TS standard for Ethernet was ratified in 2008 using DSL technology, and both cable and DSL modems often have Ethernet connectors on them.
TV and video
The television antenna can be described as "broadband" because it is capable of receiving multiple channels, whereas a single-frequency antenna or Lo-VHF is "narrowband" because it only receives 1 to 5 channels. The US federal standard FS-1037C defines "broadband" as a synonym for broadband. "Broadband" in analog video distribution has traditionally been used to refer to systems such as cable television, where individual channels are modulated on operators at a fixed frequency. In this context, baseband is an antonym term, referring to a single channel of analog video, usually in composite form with separate baseband audio. The demodulation action converts broadband video to baseband video. Optical fibers allow the signal to be transmitted further without repeating. The cable company uses a hybrid system using fiber to transmit signals to the environment and then convert the signal from light to radio frequency to be transmitted to the coaxial cable more to the home. Doing so reduces the use of having multiple heads. The head end gathers all the information from the local cable network and movie channel and then puts the information into the system.
However, "broadband video" in the context of Internet video streaming means video files that have bit-rates are high enough to require broadband Internet access for viewing. "Broadband video" is also sometimes used to describe IPTV Video on demand.
Alternate technology
The power lines have also been used for various types of data communications. Although some systems for remote control are based on narrowband signaling, modern high-speed systems use broadband signaling to achieve extremely high data rates. One example is the ITU-T G.hn standard, which provides a way of making local area networks up to 1 Gigabit/s (considered high-speed in 2014) using existing home wiring (including power grids, but also telephone lines and coaxial cables ).
In 2014, researchers at Korea Advanced Institute of Science and Technology are making progress on the manufacture of ultra-shallow broadband optical instruments.
broadband Internet
In the context of Internet access, the term "broadband" is used loosely to mean "always-on and faster access than traditional dial-up access".
While fiber optics is generally faster than wireless broadband, wireless broadband also has the potential to grow rapidly, as it provides access not only in a fixed location but anywhere. Extremely high fiber bandwidth may not be a major aspect for most customers.
A more precise definition of speed has been determined at the time, including:
- "Bigger than main tariff" (which ranges from 1.5 to 2 Mbit/s) - CCITT in "broadband service" in 1988.
- "Internet access is always on and faster than traditional dial-up access" - A National Broadband Plan 2009
- 4 Mbit/s downstream, 1 Mbit/s upstream - FCC, 2010
- 25 Mbit/s, 3 Mbit/s - FCC, 2015
Broadband Internet services in the United States are effectively treated or managed as public utilities with net neutrality rules until canceled by the FCC in December 2017.
Global bandwidth concentration
Bandwidth has historically been very unequally distributed worldwide, with increasing concentration in the digital age. Historically only 10 countries have hosted 70-75% of global telecommunication capacity (see pie chart on the right). In 2014, only 3 countries (China, US, Japan) have 50% of the potential for telecommunication bandwidth installed globally. The US lost its global leadership in terms of bandwidth installed in 2011, replaced by China, which holds more than double the national bandwidth potential by 2014 (29% versus 13% of the global total).
See also
- Mobile broadband
- Ultra-wide band
- Wireless broadband
Special nation:
- Broadband mapping in the United States
- National broadband plans from around the world
- List of Broadband Providers in the US
- List of Broadband Providers in Malaysia
References
Source of the article : Wikipedia
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