pynetdicom.pdu_primitives.A_RELEASE¶
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class
pynetdicom.pdu_primitives.
A_RELEASE
¶ An A-RELEASE primitive.
The release of an association between two AEs shall be performed through ACSE A-RELEASE request, indication, response and confirmation primitives. The initiator of the service is called a Requestor and the service-user that receives the A-RELEASE indication is called the acceptor.
Service Procedure
The user (Requestor) that desires to end the association issues an A-RELEASE request primitive. The Requestor shall not issue any other primitives other than A-ABORT until it receives an A-RELEASE confirmation primitive.
The DUL provider issues an A-RELEASE indication to the Acceptor. The Acceptor shall not issue any other primitives other than A-RELEASE response, A-ABORT request or P-DATA request.
To complete the release, the Acceptor replies using an A-RELEASE response primitive, with “affirmative” as the result parameter.
After the Acceptor issues the A-RELEASE response it shall not issue any more primitives.
The Requestor shall issue an A-RELEASE confirmation primitive always with an “affirmative” value for the Result parameter.
A user may disrupt the release by issuing an A-ABORT request.
A collision may occur when both users issue A-RELEASE requests simultaneously. In this situation both users receive an unexpect A-RELEASE indication primitive (instead of an A-RELEASE acceptance):
- The association requestor issues an A-RELEASE response primitive
- The association acceptor waits for an A-RELEASE confirmation primitive from its peer. When it receives one it issues an A-RELEASE response primitive
- The association requestor receives an A-RELEASE confirmation primitive.
When both ACSE users have received an A-RELEASE confirmation primitive the association shall be released.
Parameter Request Indication Response Confirmation reason UF UF(=) UF UF(=) user info NU NU(=) NU NU(=) result MF MF(=) U - User optionUF - User option, fixed valueC - Conditional (on user option)M - MandatoryMF - Mandatory, fixed valueNU - Not used(=) - shall have same value as request or response-
reason
¶ Fixed value of “normal”. Identifies the general level of urgency of the request.
Type: str
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result
¶ Must be None for request and indication, “affirmative” for response and confirmation.
Type: str or None
References
- DICOM Standard, Part 8, Section 7.2
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__init__
()¶ Initialize self. See help(type(self)) for accurate signature.
Methods
__init__
()Initialize self. Attributes
reason
Return the Reason parameter. result
Return the Result parameter. -
reason
Return the Reason parameter.
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result
Return the Result parameter.