Creating a DICOM Network Connection

When establishing a connection between two AEs, for the purpose of transferring DICOM data and messages, the first step is to create a DICOM Network connection.

The AE acting as an SCP must have a DICOM Network handle and the AE acting as an SCU must have a DICOM Network handle. In addition, every time an SCP accepts a new connection request from an SCU, the SCP creates another DICOM Network handle for the newly connected SCU. This provides the SCP with memory for maintaining information about the SCU and that particular connection. Steps for establishing a DICOM Network connection are given below for both the SCU and the SCP.

Creating a network handle for an SCU

Create the DICOM Network handle by calling the StartUp method. This must be done before any DICOM Network Operations methods are called.

To connect to an SCP, call the Connect method. This will generate a NetAccept event on the SCP to let the SCP know that a connection request has been received.

The SCP should respond by calling the Accept method. This will generate a NetConnect event on the SCU. At this time the DICOM Network connection has been established.

Creating a network handle for an SCP

Create the DICOM Network handle by calling the StartUp method. This must be done before any DICOM Network Operations methods are called.

To listen for incoming connection requests, call the Listen method.

When an SCU wishes to connect to an SCP, the SCU calls Connect method. This generates a NetAccept event on the SCP to let the SCP know that a connection request has been received.

The SCP should respond by calling the StartUp method, and the Accept method. Calling StartUp method creates a network handle for this specific connection and allows the SCP to maintain information about this connection. Calling the Accept method will generate a NetConnect event on the SCU. At this time the DICOM Network connection has been established. (An SCP should always accept a connection request. Once the connection is made the SCP can check the SCU and close the connection if it does not wish to maintain it. Since the connection requests are queued, if the connection is not accepted, it remains in the queue. When the next request is received, it is placed in the queue behind the first request. Calling the Accept method at this point will connect the first request, not the second, since the first request is still in the queue.)

For more information on creating SCUs and SCPs, refer to Creating an SCU or Creating an SCP.

Once the DICOM Network Connection has been made, you must create a DICOM Associate Connection before DICOM messages and data can be transferred between the AEs. For more information in creating a DICOM Associate connection, refer to Creating a DICOM Associate Connection.