SMS Subscriber Services

July 3rd, 2009 | Technical

SMS contains two basic point-to-point services. They are:

MO – Mobile originated short message

MT – Mobile terminated short message

When you send an SMS, Mobile-originated (MO) short messages are transported from the MO-capable handset to the SMSC and can be destined to other mobile subscribers or for subscribers on networks such as GSM, CDMA, Paging Networks and Internet Protocol.

Mobile-terminated (MT) short messages are transported from the SMSC to the handset and can be submitted to the SMSC by other mobile subscribers via MO-SM. For MT, a report is always returned to the SMSC either confirming the short message delivery to the handset or informing the SMSC of the short message delivery failure and identifying the reason for failure (error code). Sometimes when SMSC doesn’t receives the report of delivering, it keeps sending the SMS again and again.

Similarly, for MO, a report is always returned to the handset either confirming the short message delivery to the SMSC or informing of delivery failure and identifying the reason. Depending on the access method and the encoding of the bearer data, the point-to-point short messaging service conveys up to 160 characters in GSM networks and from 120 to 205 in IS-41 networks.

In GSM networks, the type of messaging service is identified by the protocol identifier information element, which identifies the higher-level protocol or interworking being used. Examples are telex, group 3 telefax, X.400 messaging, European Radio Messaging System (ERMES), and voice telephone.

Technorati Tags: GSM, MO, MT, SMS, SMSC

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