Method A uses a procedure of referencing the test instruments (source and meter) and measures the attenuation of the length of cable and one connection. Method B uses a procedure of referencing the test instruments and measures the attenuation of the length of cable, two connections and the length of one test cord. Method B is specified within ANSI/TIA/EIA-568-A as the procedure for testing premises cabling. The designer/specifier of the Network Solutions will generally describe the point-to-point basic link or channel to be measured, which Method to use for the measurements, the maximum expected loss of the cabling under test, and whether bi-directional measurements are required.