These are the various mobile operator settings you will require while creating dial-up modem or data card connection :
MTNL Mumbai/Delhi
Dial : *99#
balance USSD: *446#
Extra Initialization : at+cgdcont=1,”ip”,”mtnl.net”
Vodafone
Dial : *99***1#
balance USSD: *141#
Extra Initialization : AT+CGDCONT=1,”IP”,”www”
Reliance
Dial : #777
balance USSD: *367#
Extra Initialization : AT+CRM=1
Idea
Dial : *99#
balance USSD: *130#
Extra Initialization : AT+CGDCONT=1,”IP”,”ideagprs.com”
Aircel
Dial : *99#
balance USSD: *125#
Extra Initialization : AT+CGDCONT=1,”IP”,”aircelgprs.com”
Tata Docomo
Dial : *99#
balance USSD:
Extra Initialization : AT+CGDCONT=1,”IP”,”TATA.DOCOMO.INTERNET”
Airtel
Dial : *99#
balance USSD: *123#
Extra Initialization : AT+CGDCONT=1,”IP”,”airtelgprs.com”