Channel bonding
Encyclopedia
Channel bonding is a computer networking arrangement in which two or more network interface
s on a host computer are combined for redundancy or increased throughput.
On Ethernet
interfaces, channel bonding requires assistance from both the Ethernet switch
and the host computer's operating system
, which must "stripe" the delivery
of frames across the network interfaces in the same manner that I/O is striped across disks in a RAID array. For this reason, channel bonding is sometimes also called RAIN
, or "redundant array of independent network interfaces". See also EtherChannel
and 802.3ad (link aggregation).
Multiple dial-up
links over POTS can be channel-bonded together in the same manner and can come closer to achieving their aggregate bandwidth than routing schemes which simply load-balance outgoing network connections over the links. This is known as modem bonding.
Similarly, multiple DSL lines
can be bonded to give higher bandwidth; in the United Kingdom, ADSL
is sometimes bonded to give for example 512kbit/s upload bandwidth and 4 megabit/s download bandwidth, in areas that only have access to 2 megabit/s bandwidth.
Historically, channel bonding has been implemented in layer1 (physical layer) or layer2 (MAC layer). In recent years, approaches that implements bonding at higher OSI layers have been on the market such as broadband bonding
.
On 802.11 (Wi-Fi) channel bonding is used in "Super G
" technology, also referred as 108Mbit/s. It bonds two channels of classic 802.11g, which has 54Mbit/s data signaling rate
. On IEEE 802.11n
, Channel Bonding, also known as 40 MHz, is a second technology incorporated into 802.11n which can simultaneously use two separate non-overlapping channels to transmit data. Channel bonding increases the amount of data that can be transmitted. 40 MHz mode of operation uses 2 adjacent 20 MHz bands. This allows direct doubling of the PHY data rate from a single 20 MHz channel. (Note however that the MAC and user level throughput will not double.)
Network interface
Network interface may refer to:* Network interface controller, the device a computer uses to connect to a computer network* Network interface device, a demarcation point for a telephone network...
s on a host computer are combined for redundancy or increased throughput.
On Ethernet
Ethernet
Ethernet is a family of computer networking technologies for local area networks commercially introduced in 1980. Standardized in IEEE 802.3, Ethernet has largely replaced competing wired LAN technologies....
interfaces, channel bonding requires assistance from both the Ethernet switch
Network switch
A network switch or switching hub is a computer networking device that connects network segments.The term commonly refers to a multi-port network bridge that processes and routes data at the data link layer of the OSI model...
and the host computer's operating system
Operating system
An operating system is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system...
, which must "stripe" the delivery
Multilink striping
Multilink striping is a type of data striping used in telecommunications to achieve higher throughput or increase the resilience of a network connection by data aggregation over multiple network links simultaneously....
of frames across the network interfaces in the same manner that I/O is striped across disks in a RAID array. For this reason, channel bonding is sometimes also called RAIN
Redundant Array of Inexpensive Nodes
Reliable/redundant array of independent/inexpensive nodes is an architectural approach to computing and network-attached computer storage , that combines commodity or low-cost computing hardware with management software to address the reliability and availability shortcomings of non-redundant NAS...
, or "redundant array of independent network interfaces". See also EtherChannel
EtherChannel
EtherChannel is a port link aggregation technology or port-channel architecture used primarily on Cisco switches. It allows grouping of several physical Ethernet links to create one logical Ethernet link for the purpose of providing fault-tolerance and high-speed links between switches, routers and...
and 802.3ad (link aggregation).
Multiple dial-up
Dial-up access
Dial-up Internet access is a form of Internet access that uses the facilities of the public switched telephone network to establish a dialled connection to an Internet service provider via telephone lines...
links over POTS can be channel-bonded together in the same manner and can come closer to achieving their aggregate bandwidth than routing schemes which simply load-balance outgoing network connections over the links. This is known as modem bonding.
Similarly, multiple DSL lines
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 ,...
can be bonded to give higher bandwidth; in the United Kingdom, ADSL
Asymmetric Digital Subscriber Line
Asymmetric digital subscriber line is a type of digital subscriber line technology, a data communications technology that enables faster data transmission over copper telephone lines than a conventional voiceband modem can provide. It does this by utilizing frequencies that are not used by a voice...
is sometimes bonded to give for example 512kbit/s upload bandwidth and 4 megabit/s download bandwidth, in areas that only have access to 2 megabit/s bandwidth.
Historically, channel bonding has been implemented in layer1 (physical layer) or layer2 (MAC layer). In recent years, approaches that implements bonding at higher OSI layers have been on the market such as broadband bonding
Broadband bonding
Broadband bonding is a type of channel bonding that refers to aggregation of multiple channels at OSI layers at level four or above. Channels bonded can be wired links such as a T-1 or DSL line...
.
On 802.11 (Wi-Fi) channel bonding is used in "Super G
Super G (wireless networking)
Super G is Atheros' proprietary frame-bursting, compression and channel bonding technology to improve IEEE 802.11g wireless LAN performance. The throughput transmission speed limit when using Super G is claimed to be up to 40Mbit/s-60Mbit/s at a 108Mbit/s signaling rate, which is achieved through...
" technology, also referred as 108Mbit/s. It bonds two channels of classic 802.11g, which has 54Mbit/s data signaling rate
Data signaling rate
In telecommunication, data signaling rate , also known as gross bit rate, is the aggregate rate at which data pass a point in the transmission path of a data transmission system.Notes:#The DSR is usually expressed in bits per second....
. On IEEE 802.11n
IEEE 802.11n
IEEE 802.11n-2009 is an amendment to the IEEE 802.11-2007 wireless networking standard to improve network throughput over the two previous standards—802.11a and 802.11g—with a significant increase in the maximum net data rate from 54 Mbit/s to 600 Mbit/s with the use of four...
, Channel Bonding, also known as 40 MHz, is a second technology incorporated into 802.11n which can simultaneously use two separate non-overlapping channels to transmit data. Channel bonding increases the amount of data that can be transmitted. 40 MHz mode of operation uses 2 adjacent 20 MHz bands. This allows direct doubling of the PHY data rate from a single 20 MHz channel. (Note however that the MAC and user level throughput will not double.)