Remote and local systems

In an MSC network, a local system refers to a specific IMS where a message is entered. All other IMS systems are considered remote systems in regard to the specific local system.

A local transaction is a transaction that is processed in the same IMS in which it is entered. A remote transaction is a transaction that is entered into a IMS from a terminal or a link that is not processed in that IMS.

The following figure shows local and remote transactions and systems. When Transaction A is entered in IMS A, which is the local system, transaction A is processed locally. When Transaction A is entered on IMS B, which this time is the local system, it is sent across the MSC link to remote system IMS A and is processed remotely.

Figure 1. Remote and local transactions and systems
Local transaction: Transaction A is entered on and processed locally in IMS A without using MSC. Remote transaction: Transaction is entered on IMS B, sent across the MSC link, and processed on IMS A.

In the previous figure, transaction A, when entered from IMS A and processed in IMS A, is considered a local transaction. When transaction A is entered from IMS B and sent across an MSC link to be processed in IMS A, it is considered a remote transaction.