CONTROLPLANE VS DATAPLANE UPGRADE
CONTROLPLANE VS DATAPLANE SOFTWARE

CONTROLPLANE VS DATAPLANE UPGRADE

Commands issued in the operational mode upgrade software, trigger events, or show status and statistics to inspect the system’s operation. mgd directs operational requests and manages changes to the configuration database. As an operator issues operational or configuration commands to control the device, they first flow through the JUNOS management daemon (mgd). The JUNOS system an be controlled by any of several user interfaces, but always in either an operational or configuration mode. The task of managing the router is shared among the JUNOS kernel, many JUNOS daemons, and some ephemeral utility-style applications launched on demand. To transform it into a network operating system, it has been extensively modified and hardened for the specialized requirements of networking. This mature, general-purpose system provides many of the essential basic functions of an operating system, such as scheduling resources.

CONTROLPLANE VS DATAPLANE SOFTWARE

The basis of the JUNOS kernel comes from the FreeBSD UNIX operating system, an open-source software system. The Routing Engine's key component is the JUNOS Software operating system. Its role is to manage and control the behavior of the device, including the data plane and the services plane. The control plane runs on the Routing Engine. The following figure shows the router architecture: Services PICs take packet traffic from an I/O PIC, perform a service (such as GRE, NAT, and so forth) and send the result back to an I/O PIC. I/O PICs handle transit traffic: for example, packet encapsulation, input processing (CRC check), and output queuing. Each PIC is equipped with a media-specific ASIC that performs control functions tailored to the PIC's media type.

Before transmitting outgoing packets, the PICs encapsulate the packets received from the FPCs. During this process, each PIC performs framing and high-speed signaling for its media type. PICs receive incoming packets from the network and transmit outgoing packets to the network. A PIC typically occupies a single slot on an FPC. The PICs are mounted on Flexible PIC Concentrators (FPCs), which are inserted into a slot in a router. PICs provide the physical connection to various network media types. The Physical Interface Cards, or PICs (of which the Multiservices PIC is one type), like the Routing Engine, are physical hardware modules that fit into the router chassis. The PFE forwards packets through the router using ASIC-based switching. The router writes these paths to a forwarding table in the Routing Engine and then copies the same data to the forwarding table on the Packet Forwarding Engine (PFE) which actually forwards the packets. The Routing Engine operates all routing protocols and makes all routing decisions by creating a routing table that includes the best path to each destination. Normally, you perform all system authentication, system management, system configuration, and monitoring in the Routing Engine. The Routing Engine (RE) hardware module is the central control point for the system. The JUNOS platform architecture separates the control and forwarding functionality in the router: Architecture of the JUNOS SystemThe JUNOS SDK is designed to work with the unique modular architecture of Juniper routers.

Controlplane vs dataplane