How does the Mobile Terminated (MT) SMS differ from the Mobile Originated (MO) SMS?
Mobile Terminated (MT) SMS and Mobile Originated (MO) SMS refer to the direction of Short Message Service (SMS) communication between a mobile device (such as a cellphone) and the Short Message Service Center (SMSC) in a mobile network. Here's a technical breakdown of how MT SMS and MO SMS differ:
Mobile Originated (MO) SMS:
- Initiation:
- MO SMS refers to messages that are initiated by the user from the mobile device. For example, when a user sends a text message to another user, it is considered an MO SMS.
- SMS Delivery Process:
- The MO SMS is generated on the user's device and sent to the SMSC over the air interface using the Mobile-Originated Short Message Service (MO-SMS) protocol.
- The user's device communicates with the SMSC, which stores the message and routes it to the destination.
- SMSC Interaction:
- The SMSC plays a key role in MO SMS by receiving the message from the user's device, storing it temporarily, and then forwarding it to the destination address (another mobile device or an application).
- Message Format:
- MO SMS includes information such as the sender's phone number, the recipient's phone number, and the message content. The message is encapsulated in a format compatible with the SMS protocol.
- Protocol:
- MO SMS follows the MO-SMS protocol for communication between the mobile device and the SMSC.
- Network Signaling:
- MO SMS involves network signaling for message delivery and acknowledgment.
Mobile Terminated (MT) SMS:
- Initiation:
- MT SMS refers to messages that are initiated by an external entity or network and delivered to a user's mobile device. Examples include notifications, alerts, or messages sent by applications or services.
- SMS Delivery Process:
- The MT SMS is generated by an external entity or application, delivered to the SMSC, and then sent over the air interface to the recipient's mobile device using the Mobile-Terminated Short Message Service (MT-SMS) protocol.
- SMSC Interaction:
- The SMSC receives the MT SMS from external sources and processes it for delivery. It routes the message to the recipient's mobile device.
- Message Format:
- MT SMS includes information such as the sender's identity (e.g., a service provider or application), the recipient's phone number, and the message content. The message is encapsulated in a format compatible with the SMS protocol.
- Protocol:
- MT SMS follows the MT-SMS protocol for communication between the external entity or application and the SMSC.
- Network Signaling:
- MT SMS involves network signaling for the delivery of messages from external sources to the recipient's mobile device.
Key Differences:
- Initiation Source:
- MO SMS is initiated by the user from their mobile device.
- MT SMS is initiated by an external entity or application.
- Delivery Direction:
- MO SMS flows from the user's device to the network.
- MT SMS flows from an external entity or application to the user's device.
- Protocol Direction:
- MO SMS uses the MO-SMS protocol for communication from the mobile device to the SMSC.
- MT SMS uses the MT-SMS protocol for communication from external sources to the SMSC.
- Use Cases:
- MO SMS is commonly used for person-to-person communication.
- MT SMS is often used for notifications, alerts, and messages initiated by applications or services.
In summary, the main distinction between MO SMS and MT SMS lies in the direction of message initiation and delivery. MO SMS is user-initiated and delivered to the network, while MT SMS is externally initiated and delivered to the user's device. Both play essential roles in enabling different types of messaging scenarios in mobile networks.