As per The European Telecommunications Standards Institute (ETSI), GPRS has 4 coding schemes namely CS-1, CS-2, CS-3 and CS-4. CS-1 offers lowest data rate with highest data protection whereas CS-4 has highest data rates with minimal protection of data. E-GPRS uses 8-PSK modulation (transmits 3 bits per symbol) scheme and consequently has 9 coding schemes MCS-1 to MCS-9 in order of highest to lowest data protection and lowest to highest data speeds.
