ETSI - PRETS 300 452
Business Telecommunications (BTC); Special Quality Voice Bandwidth 4-Wire Analogue Leased Line (A4S); Connection Characteristics and Network Interface Presentation
|Publication Date:||1 January 1995|
This European Telecommunication Standard (ETS) specifies the technical requirements and test principles for the connection characteristics and the physical and electrical characteristics of the network interface presentation of special 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 this ETS 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 this standard have been chosen primarily for the transmission of data between terminal equipments without equalizers although there is no restriction on the use of the leased line for other types of traffic.
This ETS 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 this ETS 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.
This ETS 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 this ETS 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.
This ETS does not include details concerning the implementation of the tests nor does it include information on any regulations concerning testing.