The TRAI (Telecom Regulatory Authority of India) has divided India into various telecomscircles. Each circle is allotted to different operators in GSM and CDMA. In India length of mobile phone number is 10 digits. Each mobile number has 2 parts, first 4 digits for operator code and rest is subscriber number. Operator code is allotted by TRAI. If you find any unknown call or missed call, the operator code will support you to find out the particular location and mobile operator. Here i am presenting the operator codes for Kerala Circle.
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