The IDP receives a message (IDP Message) initiated by the SSP (service switching point) and transmitted to the service control point SCP via the INAP protocol. The
Service Switching Point In telephony, a service switching point (SSP) is the telephone exchange that initially responds, when a telephone caller dials a number, by sending a query to a central database called a service control point (SCP) so that the call can be handled. ...
(SSP) receives a message ''(ISUP Message)'' initiated by the Calling Party, this could be an IAM (Initial Address Message). The SSP evaluates the nature of the message, in the case of the IAM the called and calling party numbers. From this it determines whether it can route the call or whether it needs further instructions. In this case if the SSP does require further instructions it sends an IDP to a service control point
SCP
SCP may refer to:
Organizations Political parties
* Soviet Communist Party, the leading political party in the former Soviet Union
* Syrian Communist Party
* Sudanese Communist Party
* Scottish Christian Party
Companies
* Seattle Computer Produ ...
via an IN protocol. The protocol may be INAP but could be CAMEL, or bespoke INAP flavours such as Ericsson INAP, Nokia INAP, Siemens INAP
or Huawei INAP.
Signaling System 7
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