D.3.3.6.1 SOP class common extended negotiation sub-item structure (A-ASSOCIATE-RQ)

The SOP Class Common Extended Negotiation Sub-item shall be made of a sequence of mandatory fields, the last two of which may be zero-length. Multiple SOP Class Common 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.3-12 shows the sequence of mandatory fields.

Table D.3-12 SOP CLASS COMMON EXTENDED NEGOTIATION SUB-ITEM FIELDS (A-ASSOCIATE-RQ)

Item Bytes Field Name Description of Field
1 Item-type 57H
2 Sub-item-version This field indicates the version of the Sub-item. Fields added to the Sub-item definition in succeeding editions of the Standard will not affect the semantics of previously defined fields. The version of the Sub-item defined in this edition of the Standard is 0.
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 Reserved 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 in the SOP-class-uid field. It shall be encoded as an unsigned binary number.
7-x SOP-class-uid The SOP Class identifier encoded as a UID as defined in PS 3.5.
(x+1)-(x+2) Service-class-uid-length The Service-class-uid-length shall be the number of bytes in the Service-class-uid field. It shall be encoded as an unsigned binary number.
(x+3)-y Service-class-uid The Service Class identifier encoded as a UID as defined in PS 3.5.
(y+1)-(y+2) Related-general-sop-class-identification-length The Related-general-sop-class-identification-length shall be the number of bytes in the Related-general-sop-class-identification field. Shall be zero if no Related General SOP Classes are identified.
(y+3)-z Related-general-sop-class-identification The Related-general-sop-class-identification is a sequence of pairs of length and UID sub-fields. Each pair of sub-fields shall be formatted in accordance with Table D.3-13.
(z+1)-k Reserved Reserved for additional fields of the sub-item. Shall be zero-length for Version 0 of Sub-item definition.

Table D.3-13 RELATED-GENERAL-SOP-CLASS-IDENTIFICATION SUB-FIELDS

Bytes Sub-Field Name Description of Sub-Field
1-2 Related-general-sop-class-uid-length The Related-general-sop-class-uid-length shall be the number of bytes in the Related-general-sop-class-uid sub-field. It shall be encoded as an unsigned binary number.
3-n Related-general-sop-class-uid The Related General SOP Class identifier encoded as a UID as defined in PS 3.5.