Role of the Routing Engine (RE)

AB

The Routing Engine (RE) is a critical component of a Juniper Networks device, such as a router or switch. It performs various tasks, including managing the control plane and running the device's operating system (Junos OS). Here are the correct statements regarding the role of the RE:

A. The RE controls and monitors the chassis. This statement is true. The RE acts as the control plane of the device, which means it controls and monitors the chassis. The RE manages the system processes that handle tasks such as interface configuration, routing protocol processing, and other system-level functions.

B. The RE manages the Packet Forwarding Engine (PFE). This statement is false. The Packet Forwarding Engine (PFE) is responsible for forwarding data packets through the device. The PFE operates independently of the RE, and it has its own dedicated hardware and software resources. The RE communicates with the PFE to exchange routing and forwarding information, but it does not manage the PFE.

C. The RE receives a copy of the forwarding table from the forwarding plane. This statement is true. The forwarding plane is responsible for forwarding data packets through the device. It maintains the forwarding table, which contains information about how to forward packets based on their destination address. The RE receives a copy of the forwarding table from the forwarding plane and uses it to make routing decisions.

D. The RE implements class of service (COS). This statement is false. Class of Service (COS) is a feature of Junos OS that allows you to prioritize traffic based on various criteria, such as the type of traffic or the source and destination addresses. The RE is responsible for managing the control plane of the device and running the operating system, but it does not implement COS. Instead, COS is implemented by the PFE, which has hardware support for queuing and scheduling packets based on their priority.