4A0-220 Exam Dumps : Nokia GMPLS-Controlled Optical Networks

A network with ROADM GMPLS nodes and optical transponder connections could have both L0 and L1 restoration capabilities. L0 restoration refers to the ability of the network to recover from failures at the optical layer, such as fiber cuts or node failures, by rerouting the affected LSPs to alternative paths at the same layer. L0 restoration can be achieved by using GMPLS signaling protocols, such as RSVP-TE or CR-LDP, to establish backup LSPs in advance or on demand. L0 restoration can provide fast recovery times and high availability for optical services34. L1 restoration refers to the ability of the network to recover from failures at the sub-wavelength layer, such as transponder failures or wavelength unavailability, by rerouting the affected LSPs to alternative paths at a higher layer. L1 restoration can be achieved by using GMPLS routing protocols, such as OSPF-TE or ISIS-TE, to advertise the sub-wavelength information and availability to other nodes in the network. L1 restoration can provide more flexibility and efficiency for sub-wavelength services56. References:

• 3: GMPLS - Nokia
• 4: Generalized Multi-Protocol Label Switching - Wikipedia
• 5: Sub-Wavelength Switching - Nokia
• 6: Sub-Wavelength Switching in Optical Networks - IEEE Xplore

The Upstream Label Object in RSVP-TE is an optional object that allows a node to suggest a label to its upstream neighbor for the purpose of provisioning bidirectional LSPs. The upstream label object is carried in the Resv message and contains the label value that the node wants to use for receiving traffic from its upstream neighbor. The upstream neighbor can accept or reject the suggested label based on its local policy and resource availability. The upstream label object simplifies the label allocation process for bidirectional LSPs and avoids the need for additional signaling messages. References : RSVP-TE - Hewlett Packard Enterprise, RSVP - Nokia

The Feasibility File is a file that contains a set of target values for various optical impairment parameters, such as OSNR, CD, PMD, and PDL, that are used to determine whether a given LSP can be routed through the GMRE network. The Feasibility File is generated by the Network Planning Application (NPA) based on the network design and the service requirements. The Feasibility File is then loaded into the GMRE nodes and used by the GMPLS routing engine to perform feasibility checks for LSP requests. The Feasibility File ensures that the LSPs are routed in accordance with the network plan and the optical performance criteria12. References:

• 1: Nokia GMPLS-controlled Optical Networks Course | Nokia
• 2: GMPLS - Nokia