Exam JN0-104 topic 1 question 58 discussion

The Routing Table : Compiles information learned from routing protocols and other routing information sources Selects an active route to each destination Populates the forwarding table. The forwarding table : The router uses the active route for each destination prefix to populate the forwarding table. The forwarding table determines the outgoing interface and Layer 2 rewrite information for each packet transmitted by a device running the Junos operating system.

The correct statement about the Junos OS forwarding table is: D. The forwarding table is populated with active routes from the routing table. The forwarding table in Junos OS is responsible for storing and maintaining active routes that are selected from the routing table. The routing table contains all the available routes learned through various routing protocols or configured manually. The forwarding table, on the other hand, holds the subset of routes that are actively used for forwarding packets. The forwarding table is populated based on the information in the routing table, but it does not contain all the routes present in the routing table. It consolidates the routes that are currently active and valid for forwarding packets. By maintaining a separate forwarding table, the routing process can be optimized for efficient packet forwarding without the need to continuously refer to the complete routing table.

Ref: Junos OS Routing and Forwarding Tables | Junos OS | Juniper Networks “Junos OS Routing and Forwarding Tables … 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. …” Answer: D

D is correct