Nokia 4A0-220 Practice Exam Questions & Answers

The OSPF-TE protocol is an extension of the Open Shortest Path First (OSPF) protocol that is used to exchange information about the state of links in a GMPLS network. OSPF-TE advertises link attributes such as bandwidth, latency, priority, protection, or switching capabilities to other nodes in the same area. OSPF-TE enables nodes to build a Traffic Engineering Database (TED) that contains the topology and resource information of the network. OSPF-TE helps nodes to perform CSPF calculations and establish LSPs using RSVP-TE signaling.Reference:Open Shortest Path First - Wikipedia,Understand Open Shortest Path First (OSPF) - Design Guide,RSVP-TE and OSPF-TE extensions for GMPLS

The provisioning steps that are common in both CP to plain MP networks are node creation, CPB provisioning process, node synchronization, and CPB power balance. These steps are required to create and commission the nodes, provision the cross-connect boards (CPBs), associate the links between the nodes, synchronize the network elements (NEs) with the NFM-T, and balance the power levels of the CPBs.Reference:Nokia GMPLS-controlled Optical Networks Course | Nokia,Nokia Advanced Optical Network Management with NFM-T Course | Nokia

GMPLS is a protocol suite that extends the MPLS signaling and routing capabilities to control different types of switching technologies, such as optical, TDM, and packet switching1. GMPLS has several key features, such as self-discovery, fast protection, and restoration.Self-discovery allows GMPLS nodes to automatically discover their neighbors and exchange information about their capabilities and resources2.Fast protection enables GMPLS nodes to quickly switch to backup paths in case of a failure, without relying on the control plane3.Restoration allows GMPLS nodes to dynamically establish new paths in the network after a failure, using the control plane3. Resource optimization is not a key feature of GMPLS, but rather a potential benefit of using GMPLS to efficiently utilize the network resources and avoid over-provisioning.Reference:

1: Nokia GMPLS-controlled Optical Networks Course | Nokia

2: GMPLS - Nokia

3: Traffic survivability through Protection and Restoration Combined (PRC) - YouTube

[4]: GMPLS: Architecture and Applications - Google Books

The GMRE node address is the IP address for communication between network elements (NEs) in a GMPLS-controlled optical network. The GMRE node address is also known as the GMRE loopback address or the GMPLS node IP. It is used by GMPLS protocols such as LMP and RSVP to identify and communicate with other GMRE nodes. The GMRE node address is configured on each NE and is advertised by OSPF-TE to other nodes in the same area.Reference:Nokia 1830 PSS-4, PSS-8, PSS-16 and PSS-32 Platforms - NATO,1830 PSS Identifiers

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.Reference:Nokia GMPLS-controlled Optical Networks Course | Nokia,Nokia Advanced Optical Network Management with NFM-T Course | Nokia

The GMRE functionality is guaranteed in Nokia equipment by controller redundancy. The controller is the hardware component that runs the GMPLS software and controls the switching fabric of the node. Each node has two controllers, one active and one standby, that synchronize their states and databases. If the active controller fails, the standby controller takes over and ensures the continuity of the GMRE functionality.Reference:Nokia GMPLS-controlled Optical Networks Course | Nokia,1830 Photonic Service Switch (PSS) | Nokia

Test Mode is a feature of the Link Management Protocol (LMP) that allows testing the connectivity and functionality of a link or a TE-link. Test Mode can be initiated by either end of a link or a TE-link by sending a Test Message with a Test ID and a Test Pattern. The Test Message is sent over the control channel of the link or the TE-link and contains information such as the source and destination IP addresses, the link ID, and the test parameters. The receiving node then verifies the Test Message and sends back a TestStatusAck message with the same Test ID and Test Pattern. The TestStatusAck message indicates whether the test was successful or not, and if not, what was the reason for failure. Test Mode can be used to check if a link or a TE-link is operational, if it has any errors or faults, or if it supports certain features or capabilities.Reference:Nokia GMPLS-controlled Optical Networks Course | Nokia,RFC 4204 - Link Management Protocol (LMP)