Title: FIS - t-inactivity timer management 

PDR Reference:					98040006
Originator Reference: 				badtimer
SARPs Document Reference: 			FIS SARPs, Sections 2.4.5.3.7.9.3 and 
							2.4.5.3.7.10.1
Status: 						RESOLVED
Impact :						C (Clarification)
PDR Revision Date: 				25/06/98 (PROPOSED -> RESOLVED)
							20/05/98 (ACCEPTED -> PROPOSED)
							27/04/98 (SUBMITTED -> ACCEPTED)
PDR Submission Date:  				08/04/98
Submitting State/Organization: 		CENA, CHARME
Submitting Author Name: 			Jean, M
Submitting Author E-mail Address: 		jean@cenatls.cena.dgac.fr
Submitting Author Supplemental 
Contact Information:			
SARPs Date:  					IV2.2
SARPs Language:	 				English

Summary of Defect:
 
1/ In section 2.4.5.3.7.10.1 and table 2.4.5-8/b, the FIS protocol specification omits to request the air UC module to start the t-inactivity timer when a [FISCancelUpdateAccept] APDU is received.

2/ In section 2.4.5.3.7.9.3, the FIS protocol specification requests the air UC module to start the t-inactivity timer when receiving an [FISCancelUpdateContract] APDU in the UC-A-CANCEL state (collision situation). This is too early, the timer should be started later, actually after the reception of the [FISCancelUpdateAccept] APDU.

Impact On Interoperability:
1/ None. As the t-inactivity timer is not set, the dialogue is maintained open. 
2/ None. As the t-inactivity timer is set too early, the dialogue will be closed  sooner.

Impact on Safety:
None.

Assigned SME: 				Sub-Volume II SME

Proposed SARPs amendment: 

1/ In section 2.4.5.3.7.10.1, change
b) request .... APDU-element, and
c) enter the UC-A-IDLE state.

to:
b) request .... APDU-element, 
c) if there is no other FIS contract in place, start the t-inactivity timer, and
d) enter the UC-A-IDLE state.

2/ In section 2.4.5.3.7.9.3, change:
b) request the LI module to send the APDU to the FIS-ground-ASE,
c) if there is no other FIS contract in place, start the t-inactivity timer, and
d) remain in the UC-A-CANCEL state.

to:
b) request the LI module to send the APDU to the FIS-ground-ASE, and
c) remain in the UC-A-CANCEL state.

3/ In table 2.4.5-8/b, move the statement "if last FIS Contract start t-inactivity" from cell ([FISCancelUpdateContract] APDU, UC-A-CANCEL) to ([FISCancelCancelUpdateAccept] APDU, UC-A-CANCEL)
 
SME Recommendation to CCB: 		

This PDR might have an economical impact for airlines since the dialogue is maintained open after the cancellation of the last update contract during all the flight.

CCB Decision:				atnp_ccb_chair: SUBMITTED (08/04/98)
					atnp_ccb_chair: ACCEPTED (08/04/98)
					CCB-6 (Utrecht): RESOLVED (25/06/98)