The SOP Class Extended Negotiation Sub-item shall be made of a sequence of mandatory fields followed by the Service-class-application-information field (specific for each Service Class specification). This Sub-Item is required per the specific Service Class specifications. Multiple SOP Class Extended Negotiation Sub-Items may be present in the User Data Item of the A-ASSOCIATE-RQ, however, only one Sub-Item per SOP Class UID shall be present. Table D.3-11 shows the sequence of mandatory fields.
Table D.3-11 SOP CLASS EXTENDED NEGOTIATION SUB-ITEM FIELDS (A-ASSOCIATE-RQ and A-ASSOCIATE-AC)
|Item Bytes||Field Name||Description of Field|
|2||Reserved||This reserved field shall be sent with a value 00H but not tested to this value when received.|
|3-4||Item-Length||This Item-length shall be the number of bytes from the first byte of the following field to the last byte of the Service-class-application-information field. It shall be encoded as an unsigned binary number.|
|5-6||SOP-class-uid-length||The SOP-class-uid-length shall be the number of bytes from the first byte of the following field to the last byte of the SOP-class-uid field. It shall be encoded as an unsigned binary number.|
|7-xxx||SOP-class-uid||The SOP Class or Meta SOP Class identifier encoded as a UID as defined in PS 3.5.|
|xxx-xxx||Service-class-application-information||This field shall contain the application information specific to the Service Class specification identified by the SOP-class-uid. The semantics and value of this field is defined in the identified Service Class specification.|