Title: FIS - QOS in D-START Primitives PDR Reference: 98120014 Originator Reference: acifis09 SARPs Document Reference: FIS SARPs, Sections 2.4.5.3.12.6, 2.4.5.3.12.7, and 2.4.5.4.6 Status: RESOLVED Status: C (Clarification) PDR Revision Date: 17/05/99 (PROPOSED -> RESOLVED) 01/03/99 (ACCEPTED -> PROPOSED) 18/01/99 (SUBMITTED -> ACCEPTED) PDR Submission Date: 03/12/98 Submitting State/Organization: AIRSYS ATM (ACI) Submitting Author Name: Ilkiewicz, M / Stokes, S Submitting Author E-mail Address: michel.ilkiewicz@cdv.vly.sextant. thomson-csf.com, Shawn.Stokes@ATNSI.COM Submitting Author Supplemental Contact Information: SARPs Date: IV2.2, IV2.3 (Doc 9705 Ed1) SARPs Language: English Summary of Defect: Problem 1/ Sections 2.4.5.4.6 covers the LI exception handling requirement for the case where one of the QOS parameters is invalid within a D-START indication. However, the FIS LI should also abort if the QOS parameters received in the D-START confirm is not valid for the FIS ASE. The FIS LI requirement associated with receiving a valid D-START confirmation primitive needs to include valid QOS parameters as a precondition (see 2.4.5.3.12.7). Problem 2/ Section 2.4.5.4.6.1 should also cover the case where the QOS Routing Class are not valid. The FIS LI requirement associated with receiving a valid D-START indication (see 2.4.5.3.12.6) needs to include a valid QOS Routing class as a precondition. Problem 3/ The assumption is made in the application SARPs that when the Routing Class abstract value "ATSC - No Traffic Type Policy Preference" is requested by the DS-user, then the DSP (actually the TSP) indicates in the D-START indication (actually the T-CONNECT indication) the actual Traffic Type ("A" to "H"). This assumption is not correct, the traffic type value supplied in the indication is always identical the one provided in the request. This means that the value "ATSC - No Traffic Type Policy Preference" may be received by the called ASE. Assigned SME: Sub-Volume II SME Proposed SARPs amendment: 1/ Change section 2.4.5.3.12.6 from: Upon receipt of a D-START indication with the UserData parameter containing a FISDownlinkAPDU [FISRequest] APDU and the D-START Indication application service priority parameter has the abstract value "Aeronautical Information Service messages" and the RER Quality of Service Parameter has the abstract value "low", then: To: Upon receipt of a D-START indication with the UserData parameter containing a FISDownlinkAPDU [FISRequest] APDU and the D-START Indication application service priority parameter has the abstract value "Aeronautical Information Service messages" and the RER Quality of Service Parameter has the abstract value "low" and the Routing Class Quality of Service Parameter has one of the abstract values specified in table 4.2.6-1, then: 2/ Change section 2.4.5.3.12.7 from: Upon receipt of a D-START confirmation with a Result parameter containing the abstract value "accepted" and with a UserData parameter containing a FISUplinkAPDU [FISAccept] or [FISReject] APDU, then To: Upon receipt of a D-START confirmation with a Result parameter containing the abstract value "accepted" and with a UserData parameter containing a FISUplinkAPDU [FISAccept] or [FISReject] APDU and with a application service priority parameter containing the abstract value "Aeronautical Information Service messages" and with a RER Quality of Service Parameter containing the abstract value "low" and with a Routing Class Quality of Service Parameter containing one of the abstract values specified in table 4.2.6-1, then: 3/ Change section 2.4.5.4.6 from: D-START Indication Quality of Service Not As Expected To: D-START Quality of Service Not As Expected 4/ Change section 2.4.5.4.6.1 from: When the LI module detects that the parameter of a D-START indication primitive does not contain the abstract value "Aeronautical Information Service messages" as application service priority or does not contain the abstract value "low" as RER, the LI module shall: To: When the LI module detects that the parameter of a D-START indication primitive or of a D-START confirmation primitive does not contain the abstract value "Aeronautical Information Service messages" as application service priority or does not contain the abstract value "low" as RER or does not contain one of the abstract values specified in table 4.2.6-1 as the Routing Class, the LI module shall: SME Recommendation to CCB: - Problem 1/ There is no need at all to check the QOS parameter of a D-START confirmation. The Priority and the Routing Class provided by the initiator ASE can not be changed by the DSP or the peer ASE (see SARPs SV4 section 4.2.3.2.1, note 7). The RER may be changed only if the requested RER is "high" (seen note 10). For ADS, the requested RER is low, therefore the peer ASE cannot change the value. Therefore, if the dialogue is established, it is established with the QOS requested by the initiator ASE. Note. Anyway, when the peer ASE invokes the D-START response, the Transport connection is already set up and its QOS parameters can not be changed. Therefore changes 2 and 3 are proposed to be rejected. Problem 2/ A check on the received Traffic Type value is needed to check the requested category (ATSC/AOC/other). If the AOC category is used instead of ATSC, if for some reason there is no AOC route available, the messages could not be transmitted. No check can be done on the ATSC route class since all values are authorised. Change 1 and 4 proposed above are modified as follows: 1/ Change section 2.4.5.3.12.6 from: Upon receipt of a D-START indication with the parameter containing a FISDownlinkAPDU [FISRequest] APDU and the D-START parameter has the abstract value "Aeronautical Information Service messages" and the D-START parameter has the abstract value "low" and the D-START parameter is a valid 24 bit address, then: To: Upon receipt of a D-START indication with the parameter containing a FISDownlinkAPDU [FISRequest] APDU and the D-START parameter has the abstract value "Aeronautical Information Service messages" and the D-START parameter has the abstract value "low" and the D-START parameter identifies the traffic category "Air Traffic Service Communications (ATSC)" and the D-START parameter is a valid 24 bit address, then: 4/ Change section 2.4.5.4.6.1 from: When the LI module detects that the parameter of a D-START indication primitive does not contain the abstract value "Aeronautical Information Service messages" as application service priority or does not contain the abstract value "low" as RER, the LI module shall: To: When the LI module detects that the parameter of a D-START indication primitive does not contain the abstract value "Aeronautical Information Service messages" as application service priority or does not contain the abstract value "low" as RER or does not identify the traffic category "Air Traffic Service Communications (ATSC)", the LI module shall: Problem 3/ There is no change to the FIS SARPs since the received Routing Class value is not provided to the FIS-user. The mapping Table (2.2.1.6-1) is only application for the D-START request (not the indication) and does not need to be changed. CCB Decision: atnp-ccb_chair (SUBMITTED): 03/12/98 CCB-8 (Honolulu): ACCEPTED (18/01/99) CCB-9 (Naples): RESOLVED (17/05/99)