Integrated Services Digital Network (ISDN) - Digital Subscriber Signalling System No. one (DSS1) and Signalling System No. 7 protocols; Signalling application for the mobility management service on the alpha interface - Part 2: Protocol Implementation conformance Statement (PICS) proforma specification (Endorsement of the English version EN 301144-2 V 1.1.1 (2000-10) as German standard)