Exam JN0-105 topic 1 question 16 discussion

C. Routing Engine

C. Routing Engine

The Junos OS component responsible for maintaining the forwarding table is:C. Routing Engine Explanation: The Routing Engine (RE) is responsible for maintaining the routing table and the forwarding table. It runs the routing protocols, computes the best paths, and updates the routing table accordingly. The routing table information is then used to populate the forwarding table, which is provided to the Packet Forwarding Engine (PFE) to make packet-forwarding decisions. Clarification of Other Options: A. Packet Forwarding Engine: The PFE is responsible for the actual forwarding of packets based on the forwarding table provided by the RE, but it does not maintain the forwarding table itself. B. chassis control daemon: This component handles hardware-related functions such as power management and environmental monitoring, not routing or forwarding. D. management daemon: This component is responsible for managing system processes and providing a management interface but does not handle the forwarding table.

C. Routing Engine

C is correct According juniper document, "A major function of the Junos OS routing protocol process is to maintain the Routing Engine’s routing tables and use these tables to determine the active routes to network destinations. The routing protocol process then installs these routes into the Routing Engine’s forwarding table. The Junos OS kernel then copies this forwarding table to the Packet Forwarding Engine." We have some conclusion: => routing engine (RE) maintains routing table and forwarding table, packet forwarding engine copy forwarding table from routing engine. => routing table store all valid route, packet forwarding table only store best route.