Two-factor verification has become obligatory for E-commerce or different websites that offer online transaction facility to the users particularly for security causes. MSG91, a well-known bulk SMS service provider in India developed a definitive tool for sending the one-time password, i.e., SendOTP that not only let users send messages in the real time, but they also offer wonderful facilities such as dealing with a large database, which has decreased infrastructure price included in the method. SendOTP also lets users do investigation of each produced request. The most significant aspect that is concerned with MSG91 SendOTP product if for different reasons users do not get OTP SMS immediately, then they send Voice SMS.

The robust infrastructure of MSG91 offers the best architecture that is planned to scale a large number of SMSs in a single go. They maintain SMS logs, check delivery time, and give a list of often not succeeded numbers.