scope:

This fourth part of EN 301 061 is applicable to the Generic functional protocol for the support of supplementary services for Virtual Private Network (VPN) applications for the pan-European Integrated Services Digital Network (ISDN) by means of the Digital Subscriber Signalling System No. one (DSS1) protocol, EN 301 061-1 [1]. The present document specifies the Abstract Test Suite (ATS), and partial Protocol Implementation eXtra Information for Testing (PIXIT) proforma for the network side of the T reference point or coincident S and T reference point of implementation conforming to EN 301 061-1 [1] in compliance with the relevant requirements and in accordance with the relevant guidance given in ISO/IEC 9646.