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

The Soft Shutting Down state in the NFM-T is an administrative maintenance state where services stay up but no new traffic can be routed over the TE-link. This state is used to prepare a TE-link for maintenance or decommissioning without affecting the existing services. The NFM-T sets the TE-link to Soft Shutting Down state by sending a Notify message with the Administrative State Change flag to the head-end node of the TE-link. The head-end node then stops accepting new LSP requests over the TE-link and sends a PathErr message with the Administrative State Change flag to all the tail-end nodes of the LSPs in the TE-link. The tail-end nodes then stop sending new traffic over the LSPs and send a ResvErr message with the Administrative State Change flag to all the intermediate nodes of the LSPs. The intermediate nodes then update their routing tables and stop forwarding new traffic over the LSPs. The existing traffic, however, continues to flow over the LSPs until they are manually deleted or rerouted by the NFM-T. References : Nokia GMPLS-controlled Optical Networks Course | Nokia, Nokia Advanced Optical Network Management with NFM-T Course | Nokia

RSVP-TE Notify message is a message type defined in the RSVP-TE protocol, which is an extension of the RSVP protocol for MPLS traffic engineering. RSVP-TE Notify message is used to inform non-adjacent nodes of LSP events, such as setup, modification, or teardown. This allows the nodes to update their local state information and perform actions based on the notification. For example, a Notify message can be used to trigger a fast reroute mechanism in case of a link or node failure12. References:

• 1: RFC 3473 - Generalized Multi-Protocol Label Switching (GMPLS) Signaling Resource Reservation Protocol-Traffic Engineering (RSVP-TE) Extensions
• 2: RFC 3471 - Generalized Multi-Protocol Label Switching (GMPLS) Signaling Functional Description

The GMRE notify address is an IP address used to signal failures on downstream nodes upstream to the head node. The GMRE notify address is configured on each GMRE node and is used to send a Notify message to the head node when a failure occurs on a link or node alongthe LSP. The Notify message contains the failure information and the LSP ID. The head node can then initiate a restoration process based on the Notify message. References : Nokia GMPLS-controlled Optical Networks Course | Nokia, GMPLS - Nokia