This Recommendation | International Standard (1995) specifies a number of generally useful "test categories" such as "connection request", loop back test and data integrity test. For each of these, a standard approach is used in terms of the components of the test category such as the purpose of the test, the resources, as defined in ITU-T Rec. X.745 | ISO/IEC 10164-12 environment and content of result report, etc.

This technical corrigendum 2 revises the text to include ASN.1:1997 in 2.1, 2.2 and 13.1.