V.E.R.A. -- Virtual Entity of Relevant Acronyms (February 2016):

CIR
       Committed Information Rate (ATM)


The Free On-line Dictionary of Computing (30 December 2018):

Committed Information Rate
CIR

    (CIR) The guaranteed average data rate of a
   virtual circuit in a frame relay network.  The CIR plus
   the Excess Information Rate (EIR, burst rate) is equal to or
   less than the speed of the access port into the network.

   The term CIR includes voice and non-data packets that are not
   included in the Committed Data Rate (CDR).  CIR is generally
   used in reference to leased lines and similar classes of
   network services, not dial-up.

   (2010-05-07)