SSH EN 300 688 V1.2.1:2001

Access and Terminals (AT); 140 Mbit/s digital leased lines (D140U and D140S); Connection characteristics

Scope

The present document specifies the technical requirements and conformance tests for connection characteristics of
point-to-point 140 Mbit/s digital leased lines. These leased lines operate at:
- 139 264 kbit/s providing an information transmission capability, without restriction on binary content, (D140U);
and
- 139 264 kbit/s providing an information transmission capability, without restriction on binary content, of
138 240 kbit/s, (D140S); the remaining 1 024 kbit/s provides an 8 kHz framing structure in accordance with
ETS 300 337 (ITU-T Recommendation G.832) (see annex F).
A connection is presented via interfaces at Network Termination Points (NTPs) and includes any equipment that may
provide the NTP. Signals between NTPs are subject to impairments during their transfer over the connection. The limits
to these impairments are stated in the present document. The present document, together with the companion standard
EN 300 686 [1], defining the network interface presentation, describes the technical characteristics of the leased line.
The tests specified in the present document cannot be carried out by the leased line provider while the leased line is in
service, i.e. carrying users' traffic. Thus the tests are designed for bringing into and returning into service, although there
is no obligation to perform these tests each time a leased line is brought into or returned into service. However, if the
connection is structured, the error performance may be monitored by the leased line provider while the line is in service.
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 present document specifies the conformance tests for the connection requirements. The present document does not
include details concerning the implementation of the tests, nor does it include information on any relevant regulations.