Huawei OSN 3500 Technical Manual page 33

Protection OptiX OSN 3500 TM - SD
developed SDH cross-connect chips and powerful higher-order and lower-order
cross-connect matrix, Huawei promotes a ring networking mode based on the path
layer. That is, the protection for ring networks is based on higher-order or lower-order
paths. From this point of view, the mesh network can be considered as overlapping of
ring networks comprising various paths. Once independent protection for respective
paths can be provided, the service on the whole mesh network can be protected
accordingly.
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