DICOM Communication enable to exchange DICOM file on network easily.
For example, it is used when you send scanned image data from modality to DICOM Server and when DICOM Viewer gets various data such as image, information of patient and examination from DICOM Server.
In order to do DICOM Communication, each equipment and software need to know each IP Address, AE Title, and other information.
When you start DICOM Communication, both terminals check each other whether they can support intended features (Service Class).
Also they check mutually DICOM Communication contents (what information will be transfered by what way, etc.) that is about to start.
These contents includes what kind of information will be sent by which transfer method, and other information.
It is called "association".
When the association is established, transfer of DICOM data will be started.
After transfer is completed, Release request of the association will be executed, and then its communication will be finished.
At this association, if agreement about each communication contents cannot be established, of course communication of DICOM data will not be executed.