A transparent wavelength routed optical network has two or more different optical layer restoration schemes to provide different levels of resilience, and a restoration allocator arranged to allocate the optical layer restoration schemes, to different parts of the traffic. This can enable similar capacity for high resilience traffic as a single resilience level network, and provide additional capacity for lower resilience level traffic, which can reflect the value of the traffic. The allocator can be located centrally in a network manager, or in distributed fashion at each node, and can depend on a translation of a parameter requested by the customer. Nodes have message processors for receiving a message for reserving a path, determining if the path has become unavailable, and if so, sending a second message to collect information about any other paths still available on the same route.