In an SDN architecture, which function of a network node is centralized on a controller?
In an SDN architecture, which function of a network node is centralized on a controller?
In a Software-Defined Networking (SDN) architecture, the control plane is separated from the data plane. The SDN controller, part of the control plane, is responsible for making routing decisions. This enables a centralized approach to managing how data is routed through the network, as opposed to decentralized routing decisions in traditional network architectures.
control plane, create routing table
And data plane makes routing decisions based on control plane routing table.
760 What is the function of the controller in a software-defined network? A. forwarding packets B. multicast replication at the hardware level C. making routing decisions D. fragmenting and reassembling packets Answer C best choice
792 Which network plane is centralized and manages routing decisions? A. management plane B. data plane C. policy plane D. control plane Control plane is centralized while data plane is distributed
789 What is the function of the controller in a software-defined network? A. forwarding packets B. multicast replication at the hardware level C. setting packet-handling policies D. fragmenting and reassembling packets
Routing Decision = Routing Matching table , so its not correct , i think A the better one
Routing decisions are a function of the data plane. Creation of the IP routing table is a function of the control plane. "The term control plane refers to any action that controls the data plane. Most of these actions have to do with creating the tables used by the data plane, tables like the IP routing table, an IP Address Resolution Protocol (ARP) table, a switch MAC address table, and so on. By adding to, removing, and changing entries to the tables used by the data plane, the control plane processes control what the data plane does." https://www.ciscopress.com/articles/article.asp?p=2995354&seqNum=2
C is Correct
Making a routing decision = looking up destination route, which is an action done for a message....this a data plane process However creating routing table is a control plane process, hence A
It´s A - control plane
A SDN consists of control, data, and management planes. The control plane performs forwarding decisions and other functions, like quality of service (QoS). In contrast, the data plane is the network that switches or forwards devices handling the data packets and taking inputs from the control plane. https://www.splunk.com/en_us/blog/learn/control-plane-vs-data-plane.html#:~:text=It%20is%20responsible%20for%20routing,path%20for%20forwarding%20network%20traffic.
C. Makes a routing decision In an SDN (Software-Defined Networking) architecture, the function of making routing decisions is centralized on a controller. In SDN, the control plane, which involves tasks such as making routing decisions and managing network traffic, is separated from the data plane. The SDN controller is responsible for making decisions about how data should be forwarded through the network. This centralized control allows for more dynamic and programmable network management.
The function of a network node centralized on a controller is control plane
The answer is absolutely A. According to the 31 days before CCNA, 1) In SDN, the functions of the control plane can be completely removed from the physical networking devices and placed in a centralized application called a controller. 2) A traditional networking device contains two planes. The data plane is responsible for forwarding data as quickly as possible. To do so, it relies on tables built by the control plane. What is the tables built by the control plane?
My disdain for Cisco grows...
Im going with C In traditional networking, routing decisions are typically made by individual network nodes (routers) based on locally stored routing tables. However, in SDN, the control plane functionality, including routing decisions, is centralized on a controller. The controller determines the routing paths and policies for network traffic flow based on global network conditions and policies, then communicates these decisions to the data plane devices for forwarding. Why not A? While in traditional networking, individual network nodes (routers) create and maintain their own IP routing tables based on routing protocols and configurations, in an SDN architecture, this function is centralized on a controller. The controller, rather than individual nodes, determines the routing paths and policies for network traffic flow. Therefore, the correct answer is not A, but C.
https://www.ciscopress.com/articles/article.asp?p=2995354&seqNum=2#:~:text=A%20controller%2C%20or%20SDN%20controller,the%20devices'%20distributed%20control%20plane. https://www.linkedin.com/pulse/controller-based-sdn-architecture-baha-abu-shaqra-phd-dti-uottawa--ddzkf#:~:text=bullying%20at%20uOttawa.-,SDN%20%2F%20SDN%20system%20architecture%20%2D%20introduction,load%20balancing%20and%20security%20policies.
A is correct Controller is in Control Plane, Data Plane is one who makes routing decisions.
After researches, i found that C is more correct. Why? Well in SDN, the control functionality, including routing decisions, is centralized on a controller. The controller determines the routing paths and policies for network traffic flow based on global network conditions and policies, then communicates these decisions to the data plane devices for forwarding.
Official Cert Guide Vol 2 Page 360 "The term control plane refers to any action that controls the data plane. Most of these actions have to do with creating the tables used by the data plane, tables like the IP routing table, an IP Address Resolution Protocol (ARP) table, a switch MAC address table, and so on. By adding to, removing, and changing entries to the tables used by the data plane, the control plane processes control what the data plane does. You already know about many control plane protocols—for instance, all the IP routing protocols."
I think I unraveled the conundrum: the key is the difference between "forwarding" and "routing", by definition data plane is forwarding not routing, routing decision is not "forwarding". What data plane does is a lookup of the destination routes to find a match before the packet is forwarded. This is not a routing decision, therefore correct answer is C, because this is a function of the control plane.
From Odom book: "The term control plane refers to any action that controls the data plane. Most of these actions have to do with creating the tables used by the data plane, tables like the IP routing table, an IP Address Resolution Protocol (ARP) table, a switch MAC address table, and so on. By adding to, removing, and changing entries to the tables used by the data plane, the control plane processes control what the data plane does"