Cable internet
Encyclopedia
In telecommunication
s, cable Internet access, often shortened to cable Internet or simply cable, is a form of broadband Internet access
that uses the cable television
infrastructure. Like digital subscriber line
and fiber to the premises services, cable Internet access provides network edge connectivity (last mile
access) from the Internet service provider
to an end user. It is integrated into the cable television
infrastructure analogously to DSL which uses the existing telephone
network. Cable TV networks and telecommunications networks are the two predominant forms of residential
Internet access. Recently, both have seen increased competition from fiber deployments
, wireless, and mobile
networks.
at the customer's premises and a cable modem termination system
at a cable operator
facility, typically a cable television headend
. The two are connected via coaxial cable
or a Hybrid Fiber Coaxial
(HFC) plant. While access network
s are sometimes referred to as last-mile technologies, cable Internet systems can typically operate where the distance between the modem and the termination system is up to 100 miles (160.9 km). If the HFC network is large, the cable modem termination system can be grouped into hubs for efficient management.
Downstream
, the direction toward the user, bit rates can be as much as 400Mbit/s for business connections, and 100Mbit/s for residential service in some countries. Upstream traffic, originating at the user, ranges from 384Kbit/s to more than 20Mbit/s. One downstream channel can handle hundreds of cable modems. As the system grows, the cable modem termination system
(CMTS) can be upgraded with more downstream and upstream ports, and grouped into hubs CMTS for efficient management.
Most Data Over Cable Service Interface Specification (DOCSIS
) cable modems restrict upload and download rates, with customizable limits. These limits are set in configuration files which are downloaded to the modem using the Trivial File Transfer Protocol
, when the modem first establishes a connection to the provider's equipment. Some users have attempted to override the bandwidth cap and gain access to the full bandwidth of the system (often as much as 30 Mbit/s), by uploading their own configuration file to the cable modem - a process called uncapping
. Uncapping is almost always a violation of the Terms of Service
agreement.
, Satellite Internet, or WiMAX
, a population of users share the available bandwidth
. Some technologies share only their core network
, while some including Cable Internet and PON
also share the access network
. This arrangement allows the network operator to take advantage of statistical multiplexing
, a bandwidth
sharing technique which is employed to distribute bandwidth fairly, in order to provide an adequate level of service at an acceptable price. However, the operator has to monitor usage patterns and scale the network appropriately, to ensure that customers receive adequate service even during peak-usage times. If the network operator does not provide enough bandwidth for a particular neighborhood, the service can become sluggish if many people are using the service at the same time. Operators have been known to use a bandwidth cap
, or other bandwidth throttling technique; users' download speed is limited during peak times, if they have downloaded a large amount of data that day.
. There are those who allege that the higher stand-alone rates are not so much to more efficiently cover actually-increased cost as it is to compel the customer to bundle it with a cable television subscription (and thus to buy or lease a television receiver from the company). In the instances where a cable Internet customer insists on using stand-alone cable Internet, the cable TV signals are often removed by filtering at the line tap outside the customer's premises.
Meanwhile, Internet service providers (ISP) who purchase and then re-sell high-speed Internet access from, or through, cable companies (such as TekSavvy
in Ontario
) are generally not subject to the cable companies' higher rates, and thus can pass on regular-market-rate cable Internet to their end-user customers (giving the appearance of a "lower price"). Billing for such ISP-sponsored cable Internet services is still handled by the cable company, albeit on behalf of the ISP.
Telecommunication
Telecommunication is the transmission of information over significant distances to communicate. In earlier times, telecommunications involved the use of visual signals, such as beacons, smoke signals, semaphore telegraphs, signal flags, and optical heliographs, or audio messages via coded...
s, cable Internet access, often shortened to cable Internet or simply cable, is a form of broadband Internet access
Broadband Internet access
Broadband Internet access, often shortened to just "broadband", is a high data rate, low-latency connection to the Internet— typically contrasted with dial-up access using a 56 kbit/s modem or satellite Internet with inherently high latency....
that uses the 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...
infrastructure. Like digital subscriber line
Digital Subscriber Line
Digital subscriber line is a family of technologies that provides digital data transmission over the wires of a local telephone network. DSL originally stood for digital subscriber loop. In telecommunications marketing, the term DSL is widely understood to mean Asymmetric Digital Subscriber Line ,...
and fiber to the premises services, cable Internet access provides network edge connectivity (last mile
Last mile
The "last mile" or "last kilometer" is the final leg of delivering connectivity from a communications provider to a customer. The phrase is therefore often used by the telecommunications and cable television industries. The actual distance of this leg may be considerably more than a mile,...
access) from the Internet service provider
Internet service provider
An Internet service provider is a company that provides access to the Internet. Access ISPs directly connect customers to the Internet using copper wires, wireless or fiber-optic connections. Hosting ISPs lease server space for smaller businesses and host other people servers...
to an end user. It is integrated into the 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...
infrastructure analogously to DSL which uses the existing telephone
Telephone
The telephone , colloquially referred to as a phone, is a telecommunications device that transmits and receives sounds, usually the human voice. Telephones are a point-to-point communication system whose most basic function is to allow two people separated by large distances to talk to each other...
network. Cable TV networks and telecommunications networks are the two predominant forms of residential
Residential area
A residential area is a land use in which housing predominates, as opposed to industrial and commercial areas.Housing may vary significantly between, and through, residential areas. These include single family housing, multi-family residential, or mobile homes. Zoning for residential use may permit...
Internet access. Recently, both have seen increased competition from fiber deployments
Fiber-optic communication
Fiber-optic communication is a method of transmitting information from one place to another by sending pulses of light through an optical fiber. The light forms an electromagnetic carrier wave that is modulated to carry information...
, wireless, and mobile
Mobile Broadband
Mobile broadband is the marketing term for wireless Internet access through a portable modem, mobile phone or other mobile device.-Description:...
networks.
Hardware and bit rates
Broadband cable Internet access requires a cable modemCable 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...
at the customer's premises and a cable modem termination system
Cable modem termination system
A cable modem termination system or CMTS is a piece of equipment typically located in a cable company's headend or hubsite, and used to provide high speed data services, such as cable Internet or voice over Internet Protocol, to cable subscribers...
at a cable operator
Multi system operator
A Multiple System Operator or Multi System Operator is an operator of multiple cable television systems. A cable system in the United States, by Federal Communications Commission definition, is a facility serving a single community or a distinct governmental entity, each with its own franchise...
facility, typically a cable television headend
Cable television headend
A cable television headend is a master facility for receiving television signals for processing and distribution over a cable television system. The headend facility is normally unstaffed and surrounded by some type of security fencing and is typically a building or large shed housing electronic...
. The two are connected via coaxial cable
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...
or a Hybrid Fiber Coaxial
Hybrid fibre-coaxial
Hybrid fiber-coaxial is a telecommunications industry term for a broadband network which combines optical fibre and coaxial cable. It was commonly employed globally by cable television operators since the early 1990s.-Description:...
(HFC) plant. While access network
Access network
An access network is that part of a telecommunications network which connects subscribers to their immediate service provider. It is contrasted with the core network, which connects local providers to each other...
s are sometimes referred to as last-mile technologies, cable Internet systems can typically operate where the distance between the modem and the termination system is up to 100 miles (160.9 km). If the HFC network is large, the cable modem termination system can be grouped into hubs for efficient management.
Downstream
Downstream (computer science)
In a telecommunications network or computer network, downstream refers to data sent from a network service provider to a customer.Although the best voiceband modems are called 56 kbit/s modems, downstream speeds can be limited to a few tens of kilobits per second with even lower upstream speeds...
, the direction toward the user, bit rates can be as much as 400Mbit/s for business connections, and 100Mbit/s for residential service in some countries. Upstream traffic, originating at the user, ranges from 384Kbit/s to more than 20Mbit/s. One downstream channel can handle hundreds of cable modems. As the system grows, the cable modem termination system
Cable modem termination system
A cable modem termination system or CMTS is a piece of equipment typically located in a cable company's headend or hubsite, and used to provide high speed data services, such as cable Internet or voice over Internet Protocol, to cable subscribers...
(CMTS) can be upgraded with more downstream and upstream ports, and grouped into hubs CMTS for efficient management.
Most Data Over Cable Service Interface Specification (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...
) cable modems restrict upload and download rates, with customizable limits. These limits are set in configuration files which are downloaded to the modem using the Trivial File Transfer Protocol
Trivial File Transfer Protocol
Trivial File Transfer Protocol is a file transfer protocol known for its simplicity. It is generally used forautomated transfer of configuration or boot files between machines in a local environment....
, when the modem first establishes a connection to the provider's equipment. Some users have attempted to override the bandwidth cap and gain access to the full bandwidth of the system (often as much as 30 Mbit/s), by uploading their own configuration file to the cable modem - a process called uncapping
Uncapping
Uncapping, in the context of cable modems, refers to a number of activities performed to alter one's internet service provider modem settings. It is sometimes done for the sake of bandwidth Uncapping, in the context of cable modems, refers to a number of activities performed to alter one's internet...
. Uncapping is almost always a violation of the Terms of Service
Terms of Service
Terms of service are rules which one must agree to abide by in order to use a service. Unless in violation of consumer protection laws, such terms are usually legally binding...
agreement.
Shared bandwidth
Like most residential broadband technologies, such as FTTXFTTX
Fiber to the x is a generic term for any broadband network architecture using optical fiber to replace all or part of the usual metal local loop used for last mile telecommunications...
, Satellite Internet, or 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...
, a population of users share the available bandwidth
Bandwidth (computing)
In computer networking and computer science, bandwidth, network bandwidth, data bandwidth, or digital bandwidth is a measure of available or consumed data communication resources expressed in bits/second or multiples of it .Note that in textbooks on wireless communications, modem data transmission,...
. Some technologies share only their core network
Core network
A core network, or network core, is the central part of a telecommunication network that provides various services to customers who are connected by the access network. One of the main functions is to route telephone calls across the PSTN....
, while some including Cable Internet and PON
Passive optical network
A passive optical network is a point-to-multipoint, fiber to the premises network architecture in which unpowered optical splitters are used to enable a single optical fiber to serve multiple premises, typically 16-128. A PON consists of an optical line terminal at the service provider's central...
also share the access network
Access network
An access network is that part of a telecommunications network which connects subscribers to their immediate service provider. It is contrasted with the core network, which connects local providers to each other...
. This arrangement allows the network operator to take advantage of statistical multiplexing
Statistical multiplexing
Statistical multiplexing is a type of communication link sharing, very similar to dynamic bandwidth allocation . In statistical multiplexing, a communication channel is divided into an arbitrary number of variable bit-rate digital channels or data streams. The link sharing is adapted to the...
, a bandwidth
Bandwidth (computing)
In computer networking and computer science, bandwidth, network bandwidth, data bandwidth, or digital bandwidth is a measure of available or consumed data communication resources expressed in bits/second or multiples of it .Note that in textbooks on wireless communications, modem data transmission,...
sharing technique which is employed to distribute bandwidth fairly, in order to provide an adequate level of service at an acceptable price. However, the operator has to monitor usage patterns and scale the network appropriately, to ensure that customers receive adequate service even during peak-usage times. If the network operator does not provide enough bandwidth for a particular neighborhood, the service can become sluggish if many people are using the service at the same time. Operators have been known to use a bandwidth cap
Bandwidth cap
A bandwidth cap, also known as a bit cap, limits the transfer of a specified amount of data over a period of time. Internet service providers commonly apply a cap when a channel intended to be shared by many users becomes overloaded, or may be overloaded, by a few users...
, or other bandwidth throttling technique; users' download speed is limited during peak times, if they have downloaded a large amount of data that day.
Bundled service offerings
Many cable TV Internet access providers offer Internet access without tying it to a cable television subscription, but stand-alone cable Internet is purposely provided at higher rates—the extra cost is said to cover the cable line access much like phone companies charge a small line-access fee for having DSL Internet service without a phone subscriptionNaked DSL
A naked DSL is a digital subscriber line without a PSTN service — or the associated dial tone...
. There are those who allege that the higher stand-alone rates are not so much to more efficiently cover actually-increased cost as it is to compel the customer to bundle it with a cable television subscription (and thus to buy or lease a television receiver from the company). In the instances where a cable Internet customer insists on using stand-alone cable Internet, the cable TV signals are often removed by filtering at the line tap outside the customer's premises.
Meanwhile, Internet service providers (ISP) who purchase and then re-sell high-speed Internet access from, or through, cable companies (such as TekSavvy
TekSavvy
TekSavvy Solutions Inc. is a Canadian residential and business telecommunications company based in Chatham, Ontario, with branches in Toronto, Ottawa and Sudbury. In most of Canada it is a wholesale operator and CLEC, providing a last mile service that utilizes existing infrastructure from Bell...
in Ontario
Ontario
Ontario is a province of Canada, located in east-central Canada. It is Canada's most populous province and second largest in total area. It is home to the nation's most populous city, Toronto, and the nation's capital, Ottawa....
) are generally not subject to the cable companies' higher rates, and thus can pass on regular-market-rate cable Internet to their end-user customers (giving the appearance of a "lower price"). Billing for such ISP-sponsored cable Internet services is still handled by the cable company, albeit on behalf of the ISP.
See also
- List of cable Internet providers
- Cable modemCable modemA 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...
- Triple play (telecommunications)Triple play (telecommunications)In telecommunications, triple play service is a marketing term for the provisioning of two bandwidth-intensive services, high-speed Internet access and television, and a less bandwidth-demanding service, telephone, over a single broadband connection. Triple play focuses on a combined business...