1、INTERNATIONAL STANDARD ISOIIEC 13246 First edition 1997-l 2-15 Information technology - Telecommunications and information exchange between systems - Broadband Private Integrated Services Network - Inter-exchange signalling protocol - Signalling ATM adaptation layer Technologies de /information - Tl
2、 as a default, it supports the transfer of octet-aligned SDUs up to a maximum of 4 096 octets. - establishment and release of B-QSIG SAAL connections for assured transfer of data. B-QSIG SAAL connections are established during IPL establishment, and reside permanently. However, in certain error scen
3、arios, the SSCF may release B-QSIG SAAL connections to recover from error situations. The following SAAL services may optionally be provided: - unacknowledged transfer of data. The use of this service is not specified by the B-QSIG layer 3 signalling protocol. Functions of the SSCF and Signalling Pr
4、otocol Stack Clause 6 of ITU-T Rec. 4.2130 applies with the following exception: - only point-to-point B-QSIG SAAL connections shall be supported. In particular, B-QSIG SAAL shall not provide the broadcast capability described in clause 6/Q.2130. Definition of the Boundary of SSCF to B-QSIG-Layer 3
5、Protocols Clause 7 of ITU-T Rec. 4.2130 applies with the following exceptions: - The support of the AAL-UNITDATA primitive is not mandatory. The use of this primitive is not specified by B-QSIG layer 3 signalling protocol. - The support of layer 3 peer-to-peer messages in the AAL-ESTABLISH and AAL-R
6、ELEASE primitives is not mandatory. The use of those parameter data in these primitives is not specified by the B-QSIG layer 3 signalling protocol. Definition of the Boundary of SSCF with SSCOP Clause 8 of ITU-T Rec. Q.2130 applies with the following exception: - The support of the AA-UNITDATA primi
7、tive is not mandatory. State Transition Table of SSCF for Supporting B-QSIG Signalling Clause 9 of ITU-T Rec. Q.2130 applies with the exceptions specified in sections 8.4.3 and 8.4.4 above. Boundary to Layer Management No requirements have been identified. Applicability of SSCOP Parameters and Timer
8、s to B-QSIG Signalling The values specified in Table 4 of ITU-T Rec. Q.2130 are used as default parameters. However, parameter and timer values at the B-QSIG-IPL shall be configurable, in order to be able to select a proper set of parameter and timer values depending on the use, condition, IPL link
9、rate, round-trip delay, and receiver resequencing buffer size. As a general guide, Timer-POLL should be set to as large a value as possible that still maintains throughput efficiency and satisfies the average and maximum delivery of data. For the signalling channels at the Q reference point, no rest
10、rictions to operating at below 10 kbit/s applies. PIGS Proforma for SSCOP AND SSCOP-SSCF Annex A applies. SSCF for Semi-Permanent Connection (SPC) Control Signalling Functions for the support of semi-permanent connections are outside the scope of this International Standard. 0 ISO/IEC ISO/IEC 13246:
11、1997(E) Annex A (normative) Protocol Implementation Conformance Statement (PICS) proforma for B-QSIG SAAL A.1 Introduction A.l.l Basic reference documents for PICS proforma specifications General rules for the specification of PICS proforma are provided by ISO/IEC 9646-l. Detailed guidance for the s
12、pecification of PICS proforma is provided by ISO/IEC 9646-7; in particular the structure of a PICS proforma, the questions to be asked, the syntax and notation to be used and the semantics of the questions and expected answers. For a PICS proforma, specific acronyms and terms are used as defined in
13、ISO/IEC 9646- 1 or ISO/IEC 9646- 7, e.g.: - ICS Implementation Conformance Statement - ICS proforma Implementation Conformance Statement proforma - ICS (proforma) item A row in an ICS (proforma) table - PIGS Protocol ICS - PICS proforma Protocol ICS proforma - status (value) An allowed entry in the
14、status column for an item in an ICS proforma table - (support) answer An allowed entry in the support or supported values columns for an item in an ICS question A.1.2 A.l.3 Copyright Information Users of this specification may freely reproduce the PICS proforma of this Annex A so that it can be used
15、 for its intended purpose and may further publish the completed PICS. Structure of this PICS proforma This PICS proforma is subdivided into (sub-)clauses as follows: - Instructions (A.2) - Purpose of a PICS proforma (A.2.1) - Instructions for completing the PICS proforma (A.2.2) - Additional Informa
16、tion (A.2.3) - Exception Information (A.2.4) - Legend for the columns of the PICS proforma tables (A.2.5) - Legend for further indications of the PICS proforma tables (A.2.6) - Identification of the implementation (A.3), including: - Identification of the protocol for which this PICS applies (A.3.7) - Global statement of conformance (A.4) - SSCOP (A.5) - SSCOP-SSCF B-QSIG Protocol Capabilities (A.6)
