What is committed Information Rate?

Above the CIR, an allowance of burstable bandwidth is often given, known as the Excess Information Rate (EIR). The provider guarantees that the connection will always support the CIR rate, and sometimes the EIR rate should there be adequate bandwidth. The CIR plus excess burst rate (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.