General Packet Radio Service Assuming all meters are connected with GSM modems. winAMR IRIS generates files consisting of ‘Meter-ID’ and ‘Command’ for each meter. The files are sent to SMSC by using SMPP, SMTP or Push URL. At the SMSC, the file will be processed and it will send all the Command’s to the appropriate meters and receives the response from the meter. Again all the response will form a file will be sent back to IRIS.