ITU-T U.8 PDF

General

The hypothetical reference connections set down in the present Recommendation (see Figure 1/U.8) are intended for assessing the overall subscriber-to-subscriber performance, for determining answerback return delay, signal transfer delay and other characteristics and setting-up delays related to the hypothetical reference circuit.

The hypothetical reference connections concerning signalling aspects set down in the present Recommendation(see Figure 2/U.8 and Tables 1/U.8 to 3/U.8) are intended for specifying the transit environment where the signalling functions should be considered.