Title:			Mapping refused Association to refused Presentation / Session connection

PDR Reference:				97100031

Originator Reference: 			UL-DR 121

SARPs Document Reference: 		ULCS SARPs

Status: 					PROPOSED

PDR Revision Date: 			13/11/97

PDR Submission Date:			17/10/97

Submitting State/Organisation: 		ATNP/WG3/SG3

Submitting Author Name: 			MOULTON, J

Submitting Author E-mail Address: 	moulton@ons.ons.com

Submitting Author Supplemental 		Tel +1 703-430-2668
Contact Information:			Fax: +1 703-430-5932

SARPs Date:				Proposed ICAO Version 2.0
					(WG3 Thailand, Mar 97) 
SARPs Language:			English

Summary of Defect:

The ISO standards do not explicitly prevent a negative ACSE response PDU (AARE-) being mapped to a positive Short Presentation Connect Accept (SHORT-CPA) PPDU and a positive Short Accept (SAC) SPDU.  In the ULCS architecture, if this happened, the resulting Presentation Connection could never be re-assigned, and the associated resources would effectively be lost.  Implementations have been known to crash when unexpectedly receiving an AARE- on a positive P-CONNECT confirmation.

Assigned SME:				Sub-Volume 4 SME

SME Comment:

This is a clarification of the interaction between various ISO protocol standards and amendments.  It should have no effect on the functionality or interoperability of SARPs implementations which have interpreted the standards correctly.

Proposed SARPs amendment:

In 4.5.5.1.1, Insert new sub-paragraphs:
4.5.5.1.1.2	When a connection establishment request is accepted, the AARE (accepted) in the User-data of the positive P-CONNECT response / confirmation primitive shall map to the User-data parameter of a SHORT-CPA PPDU.
4.5.5.1.1.3	When a connection establishment request is refused, the AARE (rejected) in the User-data of the negative P-CONNECT response / confirmation primitive shall map to the User-data parameter of a SHORT-CPR PPDU.

In 4.4.4.1, Insert new sub-paragraphs:
4.4.4.1.2	When a connection establishment request is accepted, the SHORT-CPA PPDU in the SS-User-data of the positive S-CONNECT response / confirmation primitive shall map to the User-data parameter of a SAC SPDU.
4.4.4.1.3	When a connection establishment request is refused, the SHORT-CPR PPDU in the SS-User-data of the negative S-CONNECT response / confirmation primitive shall map to the User-data parameter of a SRF SPDU.


SME Recommendation to CCB: 		APPROVE the proposed amendment

CCB Decision:				ACCEPTED (CCB/3 29/10/97)