FIELD: physics.
SUBSTANCE: network nodes are considered as transmitting node, intermediate node and/or receiving node, and involved optical wavelength channels are divided into a grop of transmission optical channels, a group of reception optical channels and a group of intermediate optical channels; the group of reception optical channels is selectively separated from the protective channel of the protective fibre in order to end it on the receiving node; end-to-end passage through a group of channels on the intermediate node to the next node is carried out. For collective protection of all optical spectral channels of one node, only a pair of devices which are selective on wavelength from several possible directions is sufficient. There is no need to fit each pair of wavelength channels with a standalone spectral protection unit on a ring-shaped loop, because cost and degree of complexity are not associated with requirements for collective protection of optical wavelength channels on the ring shaped loop.
EFFECT: collective protection of multiple groups of optical channels.
22 cl, 12 dwg
