V Interfaces at the Digital Service Node (SN); Interfaces at the VB5.1 Reference Point for the Support of Broadband or Combined Narrowband and Broadband Access Networks (ANs); Part 1; Interface Specification (V1.1.1)
ETSI - European Telecommunications Standards Institute
引用标准
375
适用范围
This first part of EN 301 005 specifies the physical@ procedural and protocol requirements for interfaces at the VB5.1 reference point between an Access Network (AN) and a Service Node (SN) with flexible (provisioned) Virtual Path Link (VPL) allocation and flexible (provisioned) Virtual Channel Link (VCL) allocation (controlled by Q3 interfaces) at the VB5.1 reference point. The following Broadband Integrated Service Digital Network (B-ISDN) customer access types are supported: a) B-ISDN accesses with a User-Network Interface (UNI) according to ITU-T Recommendation I.432.2 [22] at the user side of the access network@ in particular: 1) Synchronous Digital Hierarchy (SDH) based according to ETS 300 300 [4]; 2) Cell based according to ETS 300 299 [3]@ b) B-ISDN access with a UNI according to ITU-T Recommendation I.432.3 [23] case of PDH-framed symmetrical 2 048 kbit/s (electrical interface). NOTE: B-ISDN accesses with a UNI according to future standards may require additional functionality at the VB5.1 reference point. In order to provide for a migration from narrowband to broadband access network and service node arrangements@ also narrowband access types as specified for: - V5.1 interface according to ETS 300 324-1 [6]/ITU-T Recommendation G.964; and/or - V5.2 interface according to ETS 300 347-1 [7]/ITU-T Recommendation G.965@ are supported according to the integration scenario given in ITU-T Recommendation G.902 [15]@ appendix III.2.2@ using a circuit emulation function for the transfer of circuit mode into Asynchronous Transfer Mode (ATM). In addition to these B-ISDN and narrowband customer access types@ other non-B-ISDN access types are also supported. Examples for such non-B-ISDN access types are given below: a) access types supporting asymmetric/multimedia services (i.e. video on demand) (if not part of B-ISDN access types); b) access types supporting broadcast services (if not part of B-ISDN access types); c) access types supporting LAN interconnect functionality (if not part of B-ISDN access types); d) access types that can be supported via an ATM VP cross-connect (i.e. access types according to the ATM Forum standards). The concept of Virtual User Ports (VUP)@ as described in clause 8 of the present document@ may be applied to enable any specific implementation. In accordance with the principles of B-ISDN (see CCITT Recommendation I.121 [29])@ remote access arrangements across interfaces at the VB5.1 reference point support switched and (semi-) permanent point-to-point and point-tomultipoint connections and provide on demand@ reserved and permanent services of a mono- and/or multimedia type and of a connectionless or connection-oriented nature and in a bi-directional or unidirectional configuration as supported and provided for direct access arrangements to SNs. Functions to support security management (see CCITT Recommendation X.800 [39]) related to the customer access are out of the scope of the present document. Such security management functions have no impact on the VB5.1 reference point. The present document does not specify the implementation of the requirements within the AN and does not constrain any implementation alternative as long as the functionality at the interfaces at the VB5.1 reference point as specified in the present document is met. Furthermore@ the present document does not require that an AN shall support all the customer access types listed above. The present document is not intended to define any systems or equipment in@ or connected to@ a SN via interfaces at the VB5.1 reference point. Therefore only the characteristics of the interfaces at the VB5.1 reference point are described.