Abstract: When a device is switched off, all messages for that device are stored in different distributed service centers. For example, the message from user A may be stored in SMSC A and a message from user B in SMSC B where both subscribers and respective SMSCs can even belong to different networks. When the device is switched on again it notifies its presence to the network (performed by the MSC indicating this to the HLR). As a result of this alert, different service centers that have messages pending for that device will be notified that the device has come on-line again (performed by the HLR notifying SMSC A and SMSC B). Instead of directly sending out all messages, as in the prior art, each service center instead schedules the messages in an internal queue for delivery according to a local control scheme, which achieves synchronized delivery from multiple distributed SMSCs even though there is no centralised control.

Abstract: When a device is switched off, all messages for that device are stored in different distributed service centres. For example, the message from user A may be stored in SMSC A and a message from user B in SMSC B where both subscribers and respective SMSCs can even belong to different networks. When the device is switched on again it notifies its presence to the network (performed by the MSC indicating this to the HLR). As a result of this alert, different service centres that have messages pending for that device will be notified that the device has come on-line again (performed by the HLR notifying SMSC A and SMSC B). Instead of directly sending out all messages, as in the prior art, each service centre instead schedules the messages in an internal queue for delivery according to a local control scheme, which achieves synchronised delivery from multiple distributed SMSCs even though there is no centralised control.