1、 AMERICAN NATIONAL STANDARD FOR TELECOMMUNICATIONS ATIS-0100511.2003(R2013) B-ISDN ATM Layer Cell Transfer As a leading technology and solutions development organization, ATIS brings together the top global ICT companies to advance the industrys most-pressing business priorities. Through ATIS commit
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3、novation through solutions that include standards, specifications, requirements, business use cases, software toolkits, and interoperability testing. ATIS is accredited by the American National Standards Institute (ANSI). ATIS is the North American Organizational Partner for the 3rd Generation Partn
4、ership Project (3GPP), a founding Partner of oneM2M, a member and major U.S. contributor to the International Telecommunication Union (ITU) Radio and Telecommunications sectors, and a member of the Inter-American Telecommunication Commission (CITEL). For more information, visit. AMERICAN NATIONAL ST
5、ANDARD Approval of an American National Standard requires review by ANSI that the requirements for due process, consensus, and other criteria for approval have been met by the standards developer. Consensus is established when, in the judgment of the ANSI Board of Standards Review, substantial agree
6、ment has been reached by directly and materially affected interests. Substantial agreement means much more than a simple majority, but not necessarily unanimity. Consensus requires that all views and objections be considered, and that a concerted effort be made towards their resolution. The use of A
7、merican National Standards is completely voluntary; their existence does not in any respect preclude anyone, whether he has approved the standards or not, from manufacturing, marketing, purchasing, or using products, processes, or procedures not conforming to the standards. The American National Sta
8、ndards Institute does not develop standards and will in no circumstances give an interpretation of any American National Standard. Moreover, no person shall have the right or authority to issue an interpretation of an American National Standard in the name of the American National Standards Institut
9、e. Requests for interpretations should be addressed to the secretariat or sponsor whose name appears on the title page of this standard. CAUTION NOTICE: This American National Standard may be revised or withdrawn at any time. The procedures of the American National Standards Institute require that a
10、ction be taken periodically to reaffirm, revise, or withdraw this standard. Purchasers of American National Standards may receive current information on all standards by calling or writing the American National Standards Institute. Notice of Disclaimer 1b) Defines a national ATM performance model an
11、d provisionally allocates the ITU-T Recommendation I.356 performance values to defined portions of an end-to-end national ATM connection; c) Provides supplemental information intended to assist performance characterization of national ATM services. The network performance (NP) parameters and provisi
12、onal allocations specified in T1.511-2003 apply to national public end-to-end point-to-point ATM connections and to designated portions of such connections when provided in accordance with the normative references (clause 2) and the requirements (clause 3) of this standard. The parameters are define
13、d on the basis of ATM cell transfer reference events that may be observed at physical interfaces between ATM networks and associated customer equipment, and at physical interfaces between ATM networks.2T1.511-2003 is intended to be used in the planning and offering of national B-ISDN ATM services. T
14、he intended users of this standard include ATM service providers, equipment manufacturers, and end users. This standard may be used by service providers in the planning, development, and assessment of ATM services that meet user performance needs, by equipment manufacturers as performance metrics th
15、at will affect equipment design, and by end users in evaluating performance. The scope of T1.511-2003 is summarized in Figure 1. The ATM performance parameters are defined on the basis of ATM cell transfer reference events that may be observed at physical interfaces associated with specified boundar
16、ies. For comparability and completeness, ATM performance is considered in the context of the 3 x 3 performance matrix defined in ANSI X3.102, American National Standard for Information systems Data communication systems and services User-oriented performance 1ITU-T Recommendation I.356: (1) defines
17、parameters for quantifying the ATM cell transfer performance of an international B-ISDN connection (including adjusted parameter definitions that might be used when cells do not conform with the ITU-T Recommendation I.371-negotiated traffic contract); (2) specifies provisional international performa
18、nce objectives for cell transfer, some of which depend on the users selection of QoS class; (3) defines QoS classes; and (4) allocates provisional performance objectives to the individual national portions in providing an international B-ISDN ATM connection. 2ITU-T Recommendation I.353 defines perfo
19、rmance-significant reference events upon which the ITU-T Recommendation I.356 parameter definitions are based. ATIS-0100511.2003 2 parameters. Three protocol-independent communication functions are identified in the matrix: 1) access; 2) user information transfer; and 3) disengagement. Each function
20、 is considered with respect to three general performance concerns (or “performance criteria”): 1) speed; 2) accuracy; and 3) dependability. T1.511-2003 characterizes the speed, accuracy, and dependability of user information transfer provided by national public ATM networks. Planned American Nationa
21、l Standards will define cell transfer availability parameters, and provide standard methods of measuring the cell transfer performance parameters in a national context. The national performance of the ATM layer access and disengagement functions, as well as the availability performance of switched B
22、-ISDN services, will be addressed in separate ANSI standards. T1.511-2003 is structured as follows. Clause 1 specifies the scope of the standard. Clause 2 specifies its normative references. Clause 3 specifies its requirements, many of which are direct references to ITU-T Recommendation I.356. Claus
23、e 4 specifies the national ATM performance model. Clause 5 specifies the (provisional) national ATM cell transfer performance allocations. Clause 6 specifies bringing-into-service (BIS) criteria for voice virtual channels. The informative annexes provide supplemental (i.e., non-normative) informatio
24、n intended to assist application of ITU-T Recommendation I.356 and T1.511-2003. NOTES 1 Consistent by reference to ITU-T Recommendation I.356, the T1.511-2003 parameters may be augmented or modified based upon further study of the requirements of the services to be supported on B-ISDNs. 2 Consistent
25、 by reference to ITU-T Recommendation I.356, the T1.511-2003 parameters are intended to characterize ATM connections in the available state. 3 Consistent by reference to ITU-T Recommendation I.356, the T1.511-2003 parameters apply to cell streams in which all cells conform with the negotiated ITU-T
26、Recommendation I.371 traffic contract. 4 The recommended ATM performance values to be achieved nationally for each of the defined parameters depend on which Quality of Service (QoS) class the end-users and network providers agree upon for the connection. T1.511-2003 (clause 5) uses the four QoS clas
27、ses defined in ITU-T Recommendation I.356 (8). 5 Consistent by reference to ITU-T Recommendation I.356, the T1.511-2003 parameters are equally applicable to national virtual channel connections (VCCs) and national virtual path connections (VPCs). The national allocations in clause 5 are also applica
28、ble to both VCCs and VPCs. However, the end users (customers) of a national VPC will often be two networks that use the VPC to support individual VCCs. In order to meet the end-to-end values on each VCC, the performance of the supporting VPC must be better. The degree to which the VPC performance mu
29、st be better than VCC performance is for further study. 2 Normative References The following standards contain provisions which, through reference in this text, constitute provisions of this American National Standard. At the time of publication, the editions indicated were valid. All standards are
30、subject to revision, and parties to agreements based on this American National Standard are encouraged to investigate the possibility of applying the most recent edition of the standards indicated below. T1.514-2001, Network performance parameters and objectives for dedicated digital services SONET
31、bit rates.3T1.627-1993 (R1999), Broadband ISDN ATM layer functionality and specification. 3T1.654-1996, Broadband integrated services digital network (B-ISDN) operations and maintenance principles and functions. 33This document is available from the Alliance for Telecommunications Industry Solutions
32、, 1200 G Street N.W., Suite 500, Washington, DC 20005. . ATIS-0100511.2003 3 ANSI X3.102-1992, Information systems Data communication systems and services User-oriented performance parameters.4ITU-T Recommendation G.711, Pulse code modulation (PCM) of voice frequencies, 1988.5ITU-T Recommendation I.
33、353, Reference events for defining ISDN and B-ISDN performance parameters, 1996.5ITU-T Recommendation I.356, B-ISDN ATM layer cell transfer performance, 2000.5ITU-T Recommendation I.371, Traffic control and congestion control in B-ISDN, 1996.5ITU-T Recommendation M.2201, Performance objectives, allo
34、cations and limits for bringing-into-service and maintenance of international ATM virtual path and virtual channel connections, 2001.5ITU- T Recommendation Q.2931, B-ISDN. Digital subscriber signalling system no. 2 (DSS 2). User-network interface (UNI) layer 3 specification for basic call/connection
35、 control, 1996.54Available from American National Standards Institute, 25 West 43rdStreet, 4thFloor, New York, NY 10036. 5This document is available from the International Telecommunications Union. ATIS-0100511.2003 4 * Subject of planned ANSI supplements or standards. Figure 1 - Scope of T1.511-200
36、3 ATIS-0100511.2003 5 3 Requirements The American National Standard for B-ISDN ATM layer cell transfer performance shall be the text of ITU-T Recommendation I.356, B-ISDN ATM layer cell transfer performance, 1996, with the modifications specified in this clause. 6NOTE The informative annex of T1.511
37、-2003 provides supplemental information intended to assist application of ITU-T Recommendation I.356 and T1.511-2003. The following subclauses highlight the applicability of individual sections from ITU-T Recommendation I.356. 3.1 Scope The scope of T1.511-2003 (clause 1) replaces the scope of ITU-T
38、 Recommendation I.356 (1). 3.2 References The normative references of T1.511-2003 (clause 2) replace the references of ITU-T Recommendation I.356 (2). 3.3 Abbreviations Errored cell outcome; Tagged cell outcome; Misinserted cell outcome; Lost cell outcome; and Severely errored cell block outcome. Se
39、e Annex A for clarification concerning the tagged cell outcome. 3.6 ATM performance parameters The ATM performance parameters defined in ITU-T Recommendation I.356 (6) apply in the national context of T1.511-2003. These parameters are: Cell error ratio (CER); Cell loss ratio for the high priority ce
40、lls (CLR0); Cell loss ratio for the aggregate cell stream (CLR0+1); Cell loss ratio for the low priority cells (CLR1); ATIS-0100511.2003 8 Cell misinsertion rate (CMR); Severely errored cell block ratio (SECBR); Cell transfer delay (CTD); 1-point cell delay variation at an MP (1-point CDV); and 2-po
41、int cell delay variation between two MPs (2-point CDV). 3.7 Network performance when some cells are non-conforming ITU-T Recommendation I.356 (7) does not place any requirements on network operators and, in particular, does not include any requirements for national networks. The material in ITU-T Re
42、commendation I.356 (7) illustrates one way of extending the ATM performance parameter definitions and measurement methods to cell streams in which some cells do not conform with the negotiated traffic contract. (See Annex A for more information.) 3.8 Network performance objectives The ATM QoS classe
43、s defined in ITU-T Recommendation I.356 (8) apply in the national context of T1.511-2003. These QoS classes are: Class 1 (stringent class); Class 2 (tolerant class); Class 3 (bi-level class); and Class U (unbounded/unspecified class). ITU-T Recommendation I.356 (8) includes numeric objectives for ce
44、rtain performance parameters applicable to end-to-end international connections. The national performance allocations specified in T1.511-2003 (clause 5) are consistent with the ITU-T Recommendation I.356 objectives. No objectives are specified for CLR1or 1-point CDV. 3.9 Allocation of the performan
45、ce objectives ITU-T Recommendation I.356 (9) includes allocations of the ITU-T Recommendation I.356 (8) performance objectives to the national portions of an end-to-end international ATM connection. The performance allocations specified within the national context of T1.511-2003 (clause 5) are consi
46、stent with these allocations. 3.10 Relationship between ATM layer NP and the NP of AAL type 1 for CBR services The network performance relationships described in ITU-T Recommendation I.356 (Annex A) apply in the national context of T1.511-2003. ATIS-0100511.2003 9 3.11 Cell transfer delay, 1-point C
47、DV, and 2-point CDV characteristics The cell transfer performance characteristics described in ITU-T Recommendation I.356 (Annex B) apply in the national context T1.511-2003. 3.12 Cell transfer performance measurement methods The measurement methods described in ITU-T Recommendation I.356 (Annex C)
48、apply in the national context T1.511-2003. 3.13 Assessing the performance of a UPC/NPC mechanism Appendix I of ITU-T Recommendation I.356 is not part of T1.511-2003. 3.14 Hypothetical reference connections for validating the ATM performance objectives Appendix II of ITU-T Recommendation I.356 is not
49、 part of T1.511-2003. 3.15 Example applications of the allocation rules of ITU-T Recommendation I.356 (9.5, 9.6, 9.7) Appendix III of ITU-T Recommendation I.356 is not part of T1.511-2003. 4 National ATM performance model This clause defines an ATM performance model that extends the performance model defined in ITU-T Recommendation I.356 (4) to provide a basis for national ATM layer cell transfer performance definition and specification. The layered nature of B-ISDN performance issues is illustrated in Figure 3/I.356 of ITU-T
