Mobile Originated (MO)
Mobile Originated (MO) messaging refers to a voice call or SMS message that originates from a mobile phone. More precisely in the case of SMS, this is an SMS text message that the customer/subscriber sends from their mobile device to another mobile user or application. The term also describes the communications leg between the customer/subscriber and the SMSC.
See Melrose Labs Tyr SMS Gateway
Melrose Labs: Our mission is to deliver pivotal services in cloud communications across mobile, fixed-line and internet for enterprises of all sizes. Through these services, we help businesses and other organisations communicate better with their staff and customers, and by doing so increase their success.