ETSI - ETS 300 451
Business Telecommunications (BTC); Ordinary Quality Voice Bandwidth 4-Wire Analogue Leased Line (A4O); Connection Characteristics and Network Interface Presentation
|Publication Date:||1 January 1996|
The present document specifies the technical requirements and test principles for the connection characteristics and the physical and electrical characteristics (except safety, overvoltage and EMC aspects) of the network interface presentation of ordinary quality, voice bandwidth, 4-wire, analogue leased lines, provided as part of the minimum set under the Council Directive on the application of Open Network Provision (ONP) to leased lines (92/94/EEC).
A connection is presented via interfaces at Network Termination Points (NTPs) and includes any equipment that may provide the NTP. Signals between terminal equipments are subject to impairments during their transfer over the connection. The limits to these impairments are stated in the present document although in practice the overall performance may be considerably better.
The leased line provides access to the voice bandwidth (300 Hz to 3 400 Hz) with no restrictions on the use of the frequencies. The requirements of the present document have been chosen primarily for the transmission of telephony although there is no restriction on the use of the leased line for other types of traffic.
The present document is applicable for leased lines, including part time leased lines, for which the establishment or release does not require any protocol exchange or other intervention at the NTP.
The tests specified in the present document cannot be carried out, nor can performance be monitored by the leased line provider, while the leased line is in service, i.e. carrying user's traffic. Thus the tests are designed for bringing into and returning into service, although there is no obligation to perform these tests each time the leased line is brought into or returned into service.
The present document covers the physical, mechanical and electrical characteristics of the network interface and specifies the conformance tests for the connection characteristics and network interface. Some of the tests described in the present document are not designed to be applied to the interface of an installed leased line; such tests may be applied to equipment of the kind used to provide the interface.
The present document does not include details concerning the implementation of the tests nor does it include information on any regulations concerning testing.