Software Defined Network SDN
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SDN Quick Summary Most traditional devices use a distributed architecture, in which each control plane is resided in a networking device. Therefore they need to communicate with each other via messages to work correctly. In constrast to distributed architecture, centralized (or controller-based) architectures centralizes the control of networking devices into one device, called SDN controller. The SDN controller has a global view of the network, and it uses common management protocols to monitor and configure the network devices. An example of SDN is Cisco ACI. As we took the control planes off networking devices but not data planes so we need a way to communicate with them. So we put a southbound interface (SBI) at the bottom of SDN controller for this task. An SBI communicates with the devices via an application programming interface (API).
Now, in turn, the networking administrators and SDN applications want to control the controller! So the controller need a northbound interface (NBI) to communicate with us. The NBI applications included various network services, including network virtualization, dynamic virtual network provisioning, firewall monitoring, user identity management and access policy control.
SDN northbound APIs are usually RESTful APIs used to communicate between the SDN Controller and the services and applications running over the network. OpenFlow and NETCONF are Southbound APIs used for most SDN implementations. |
Question 1
Question 2
Explanation
What Cisco DNA Center enables you to do
Automate: Save time by using a single dashboard to manage and automate your network. Quickly scale your business with intuitive workflows and reusable templates. Configure and provision thousands of network devices across your enterprise in minutes, not hours.
Secure policy: Deploy group-based secure access and network segmentation based on business needs. With Cisco DNA Center, you apply policy to users and applications instead of to your network devices. Automation reduces manual operations and the costs associated with human errors, resulting in more uptime and improved security. Assurance then assesses the network and uses context to turn data into intelligence, making sure that changes in the network device policies achieve your intent.
Assurance: Monitor, identify, and react in real time to changing network and wireless conditions. Cisco DNA Center uses your network’s wired and wireless devices to create sensors everywhere, providing real-time feedback based on actual network conditions. The Cisco DNA Assurance engine correlates network sensor insights with streaming telemetry and compares this with the current context of these data sources. With a quick check of the health scores on the Cisco DNA Center dashboard, you can see where there is a performance issue and identify the most likely cause in minutes.
Extend ecosystem: With the new Cisco DNA Center platform, IT can now integrate Cisco® solutions and third-party technologies into a single network operation for streamlining IT workflows and increasing business value and innovation. Cisco DNA Center allows you to run the network with open interfaces with IT and business applications, integrates across IT operations and technology domains, and can manage heterogeneous network devices.
Question 3
Explanation
The Southbound API is used to communicate between Controllers and network devices.
q1 why is it d and not b?
I would guess it would be because an API is interface between programs, a console is typically an interface between a human and a program or device?
why q1 is D and not A? northbound are from controller and applications, so the answer more similar to applications is cloud..
any one to share study maretial
Which type of API is being used when a security application notifies a controller within a software-defined network architecture about a specific security threat?
A. southbound API
B. westbound API
C. eastbound API
D. northbound API
Answer should B, Westbound.
Westbound also known as Integration APIs, is used to publish network data, events and notifications.
Northboaund also known as Intent APIs,is used to define configuration and policies.
Does anyone have a different perspective?
https://blogs.cisco.com/networking/with-apis-cisco-dna-center-can-improve-your-competitive-advantage