scope:

This standard gives guidance on call routing during the implementation of ISDN in Europe, as defined by the Memorandum of Understanding on the Implementation of the ISDN in Europe in 1992.

It is applicable to the functions required at ISDN international gateways and international transit exchanges for routing and network planning in order to achieve practical international interconnection of networks.

The relevant CCITT routing recommendations are identified and clarifications and additions to them are provided where necessary.

This standard is produced in connection with the implementation of ISDN services, using either ISUP version 1 or CEPT No. 7 TUP+ in the international network. This standard covers the services which are supported by ISUP version 1.

The following bearer and teleservices are not within the scope of this standard:

- 2 X 64 kbit/s circuit mode bearer service;

- videotex photographic mode;

- computerised communication;

- teleaction;

- audiographic teleconferencing;

- 7 kHz telephony;

- videotelephony.