ETSI EN 301 813-4 English Printed Edition English PDF Integrated Services Digital Network (ISDN) and Broadband Integrated Services Digital Network (B-ISDN); Generic Addressing and Transport (GAT) protocol; Part 4: Abstract Test Suite (ATS) and partial Protocol Implementation eXtra Information for Testing (PIXIT) proforma specification

standard published 02/01/2002 by European Telecommunications Standards Institute