CCITT Rec. M.1025 (11/1988) – CHARACTERISTICS OF SPECIAL QUALITY INTERNATIONAL LEASED CIRCUITS WITH BASIC BANDWIDTH CONDITIONING
1 Scope
2 Characteristics
    2.1 Nominal overall loss
    2.2 Loss/frequency distortion
    2.3 Group-delay distortion
    2.4 Variation of overall loss with time
    2.5 Random circuit noise
    2.6 Impulsive noise
    2.7 Phase jitter
    2.8 Total distortion (including quantizing distortion)
    2.9 Single tone interference
    2.10 Frequency error
    2.11 Harmonic and intermodulation distortion
ANNEX A (to Recommendation M.1025) – Noise and distortion
    A.1 Random circuit noise
    A.2 Total distortion
References