MMSC-GW stands for "Multimedia Messaging Service Center Gateway". It is a component in a telecommunications network that enables the transmission and delivery of multimedia messages, such as pictures, videos, and audio recordings, between mobile devices. The MMSC-GW acts as an interface between the mobile network and the internet, and it provides functions such as message conversion, routing, and delivery.
When a user sends a multimedia message from their mobile device, the message is first sent to the MMSC-GW, which converts the message into a format that can be transmitted over the mobile network. The MMSC-GW then routes the message to the appropriate recipient based on the destination phone number.