In a
Frame Relay
Frame Relay is a standardized wide area network (WAN) technology that specifies the physical and data link layers of digital telecommunications channels using a packet switching methodology. Originally designed for transport across Integrated ...
network, committed information rate (CIR) is the
bandwidth
Bandwidth commonly refers to:
* Bandwidth (signal processing) or ''analog bandwidth'', ''frequency bandwidth'', or ''radio bandwidth'', a measure of the width of a frequency range
* Bandwidth (computing), the rate of data transfer, bit rate or thr ...
for a
virtual circuit
A virtual circuit (VC) is a means of transporting data over a data network, based on packet switching and in which a connection is established within the network between two endpoints. The network, rather than having a fixed data rate reservation ...
guaranteed by an
internet service provider
An Internet service provider (ISP) is an organization that provides services for accessing, using, or participating in the Internet. ISPs can be organized in various forms, such as commercial, community-owned, non-profit, or otherwise privatel ...
to work under normal conditions. Committed data rate (CDR) is the
payload
Payload is the object or the entity which is being carried by an aircraft or launch vehicle. Sometimes payload also refers to the carrying capacity of an aircraft or launch vehicle, usually measured in terms of weight. Depending on the nature of ...
portion of the CIR.
At any given time, the available bandwidth ''should not'' fall below this committed figure. The bandwidth is usually expressed in
kilobits per second
In telecommunications, data-transfer rate is the average number of bits ( bitrate), characters or symbols ( baudrate), or data blocks per unit time passing through a communication link in a data-transmission system. Common data rate units are mul ...
(kbit/s).
Above the CIR, an allowance of
burstable bandwidth is often given, whose value can be expressed in terms of an additional rate, known as the
excess information rate (EIR), or as its absolute value,
peak information rate (PIR). The provider guarantees that the connection will always support the CIR rate, and sometimes the EIR rate provided that there is adequate bandwidth. The PIR, i.e. the CIR plus EIR, is either equal to or less than the speed of the access port into the network. Frame Relay carriers define and package CIRs differently, and CIRs are adjusted with experience.
See also
*
Information rate
In telecommunications and computing, bit rate (bitrate or as a variable ''R'') is the number of bits that are conveyed or processed per unit of time.
The bit rate is expressed in the unit bit per second (symbol: bit/s), often in conjunction w ...
*
Throughput
Network throughput (or just throughput, when in context) refers to the rate of message delivery over a communication channel, such as Ethernet or packet radio, in a communication network. The data that these messages contain may be delivered ov ...
Notes
References
Network performance
Computer network analysis
Temporal rates
Frame Relay
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