When a recipient receives a message from any provider or bank etc., a sender ID along with a prefix is displayed in the inbox. For example- VM-SBGMBS, DM-Google, BR-Amazon, and QP-SMSAPI etc.

The prefixes VM, BW etc. are displayed because SMS is sent in huge numbers via bulk SMS. SMS providers follow rules framed by Telecom Regulatory Authority of India (TRAI) and according to TRAI rules,

Sender ID should be restricted to 6 characters. (Ex. QP-TxTAPI)

The prefix has a specific meaning. That is:

The first character of prefix displays the operator name-

The latter character represents the location of the operator through which the message is received:

Therefore, if you get a message like QP-TxTAPI, you can interpret that you've got the message through the Videocon operator from Punjab.