ITU-T G.652 Fibre
ITU-T G.652 is the international standard for ordinary single-mode optical fibre, the type most widely used in telecoms networks.
What is G.652 fibre?
G.652 fibre is "non-dispersion-shifted": it is optimised for the 1310 nm window but also works well at 1550 nm. The G.652.D variant is the usual choice for feeder and distribution cables in fibre access networks. For drop cables and wiring inside buildings, where fibres are bent tightly, operators often use bend-insensitive G.657 fibre, which is compatible with G.652.