61204025L1-1C © 2004 ADTRAN, Inc 55Appendix C Acronyms/AbbreviationsACK acknowledgmentANSI American National Standards InstituteAR access rateARP address resolution protocolasync asynchronousBECN backward explicit congestion notificationBOP bit oriented protocolCCITT Consultive Committee for International Telephony and TelegraphyCD carrier detectCO central officeCPE customer premise equipmentCRC cyclic redundancy checkCS clear to sendCSU channel service unitCTS clear to senddB decibelDBU Dial backupDCD data carrier detectDCE data communications equipmentDDS digital data serviceDE discard eligibleDLCI data link connection identifierDSAP directory scope analysis programDSR data set readyDSU data service unitDTE data terminal equipmentDTR data terminal readyFDL facility data linkFECN forward explicit congestion notificationFEP front end processorFIFO first in first out
