In this Recommendation, measurements relating to CCIIT Signalling System No.7 are specified. The specification of measurements for CCITT Signalling system No. 6 has not been defined in such a sîructured way as for CCITT Signalling System No 7. However, some of the measurements indicated for CCTI' Signalling System No. 7 may also be valid for CCI" Signalling System No. 6 (albeit with slight variation in meaning), and may be used for the network operations functions of the relevant networks.