ITU-T Rec. G.651 (1988) – Characteristics of a 50/125 µm multimode graded index optical fibre cable
1 Fibre characteristics
    1.1 Geometrical characteristics of the fibre
    1.2 Optical properties of the fibre
    1.3 Material properties of the fibre
2 Factory length specifications
    2.1 Attenuation coefficient
    2.2 Baseband response
3 Elementary cable sections
    3.1 Attenuation
    3.2 Baseband response (overall -3 dB optical bandwith)
ANNEX A – Meaning of the terms used in the Recommendation
A.1 alternative test method (ATM)
A.2 attenuation coefficient
A.3 bandwidth (of an optical fibre)
A.4 chromatic dispersion
A.5 chromatic dispersion coefficient
A.6 cladding
A.7 cladding mode stripper
A.8 core
A.9 core area
A.10 core (cladding) centre
A.11 core (cladding) diameter
A.12 core (cladding) diameter deviation
A.13 core/cladding concentricity error
A.14 core (cladding) tolerance field
A.15 four concentric circles near field template
A.16 four concentric circles refractive index template
A.17 maximum theoretical numerical aperture
A.18 mode filter
A.19 mode scrambler; mode mixer
A.20 non-circularity of core (cladding)
A.21 numerical aperture
A.22 reference surface
A.23 reference test method (RTM)
A.24 (refractive) index profile
ANNEX B – Test methods
B.1 Introduction
B.2 The reference test methods for geometrical parameters and the alternative test method for numerical aperture: ...
B.3 Alternative test method for geometrical parameters: the near-field technique
B.4 Reference test method for the numerical aperture: far-field distribution
APPENDIX I
I.1 Core centre and diameter
I.2 Cladding centre and diameter