Automation and programmability on the CCNA: controllers, REST APIs, JSON and AI

How does the separation of the control plane and data plane in a controller-based network automation architecture improve network management?

1. AOption A: It decentralizes network management by moving more intelligence into each individual device.
   Note on A

   Decentralized intelligence is the traditional model, where every device runs its own control plane.

2. BOption B: It centralizes network intelligence, simplifying configuration and policy across devices.
   Note on B

   Correct: the controller holds the control logic and pushes policy, so changes are made once instead of box by box.

3. COption C: It requires each device to individually process network policies in real time.
   Note on C

   Per-device policy processing is what controller-based designs remove.

4. DOption D: It increases the need for manual configuration for each network component.
   Note on D

   Centralizing control reduces manual per-device configuration rather than increasing it.

What is the primary benefit of generative AI in network operations?

1. AOption A: It physically installs network equipment without human intervention
   Note on A

   AI tools work with data and text; installing hardware still needs people.

2. BOption B: It generates revenue directly by optimizing network traffic patterns for billing
   Note on B

   Earning revenue is not an operational function of generative AI in the network.

3. COption C: It can draft configurations, scripts, and documentation from stated requirements
   Note on C

   Correct: generative models produce new text such as configs, scripts and documentation, which an engineer then reviews.

4. DOption D: It completely eliminates the need for network engineers to review changes
   Note on D

   Generated output can be wrong, so engineers still check and approve changes.

Which protocol is primarily used for automating the configuration of network devices?

1. AOption A: TFTP
   Note on A

   TFTP only copies files such as images and configs, with no structured configuration model.

2. BOption B: HTTPS
   Note on B

   HTTPS is a transport; RESTCONF runs over it, but HTTPS alone does not define device configuration.

3. COption C: SSH
   Note on C

   SSH gives secure CLI access and carries NETCONF, but by itself it is a session protocol, not a configuration API.

4. DOption D: NETCONF
   Note on D

   Correct: NETCONF reads and edits device configuration as structured XML based on YANG models, usually over SSH port 830.

How can predictive AI algorithms improve automated network management in controller-based architectures?

1. AOption A: They only analyze security threats and ignore performance metrics.
   Note on A

   Predictive models cover performance as well as security, such as link or capacity trends.

2. BOption B: They automatically generate network configurations without any historical context.
   Note on B

   Prediction depends on historical data; without it there is nothing to learn patterns from.

3. COption C: They forecast likely network issues from telemetry so problems are fixed early.
   Note on C

   Correct: models trained on historical and live telemetry spot trends that lead to failures, so teams act before users are hit.

4. DOption D: They decentralize network management into isolated device-level actions.
   Note on D

   Predictive analytics usually runs centrally on the controller or in the cloud, not as isolated device actions.

Which of the following shows the correct XML object format?

1. AOption A: <Pets><Max>dog</Max><Whiskers>cat</Whiskers>Puffy > fish</Pets>
   Note on A

   The last element has no tags, so ‘Puffy > fish’ is stray text and the document is not well formed.

2. BOption B: $Pets : {<Max>$dog<Max>, <Whiskers>$cat<Whiskers>, <Puffy>$fish<Puffy>}
   Note on B

   Dollar signs, colons and braces are not XML syntax, and the tags are never closed.

3. COption C: <Pets><Max>dog</Max><Whiskers>cat</Whiskers><Puffy>fish</Puffy></Pets>
   Note on C

   Correct: every element has a matching start and end tag, and all three are nested inside the Pets root element.

4. DOption D: <Pets>[<Max>dog</Max>, <Whiskers>cat<Whiskers>, <Puffy>fish</Puffy>]</Pets>
   Note on D

   Square brackets and commas are JSON-style syntax, and the Whiskers element is never closed.

In a JSON-encoded data structure, what symbol is used to denote an object?

1. AOption A: ()
   Note on A

   Parentheses are not part of JSON syntax at all.

2. BOption B: {}
   Note on B

   Correct: curly braces enclose a JSON object, a set of key-value pairs such as {“hostname”: “R1”}.

3. COption C: []
   Note on C

   Square brackets mark an array, an ordered list of values, not an object.

4. DOption D: <>
   Note on D

   Angle brackets belong to XML tags, not JSON.

Which of the following is a valid JSON format for an API response?

1. AOption A: {status: “success”, data: {id: 123, name: “John Doe”}}
   Note on A

   The keys are not in double quotes, which JSON requires for every key.

2. BOption B: {“status”: “success”; “data”: {“id”: 123, “name”: “John Doe”}}
   Note on B

   A semicolon separates the pairs, but JSON only allows commas.

3. COption C: {“status”: “success”, “data”: {“id”: 123, “name”: “John Doe”}
   Note on C

   The outer object is never closed; one closing brace is missing at the end.

4. DOption D: {“status”: “success”, “data”: {“id”: 123, “name”: “John Doe”}}
   Note on D

   Correct: quoted keys, colons between keys and values, commas between pairs and balanced braces make it valid.

In Ansible, which type of file contains an ordered list of tasks that need to be executed?

1. AOption A: Inventory
   Note on A

   The inventory lists the hosts and groups Ansible manages, not the tasks.

2. BOption B: Module
   Note on B

   A module is a single unit of work, such as ios_config, that a task calls.

3. COption C: Playbook
   Note on C

   Correct: a playbook is a YAML file of plays, each running an ordered list of tasks against inventory hosts.

4. DOption D: Role
   Note on D

   A role packages tasks, variables and templates for reuse and is pulled into a playbook.

In REST-based API communications for network automation, what is the primary role of the HTTP verb ‘PUT’?

1. AOption A: It retrieves a resource without altering its state.
   Note on A

   Reading a resource without changing it is the job of GET.

2. BOption B: It deletes a resource from the network.
   Note on B

   Removing a resource is done with DELETE.

3. COption C: It updates an existing resource and is idempotent.
   Note on C

   Correct: PUT replaces the resource with the supplied state, so sending the same request twice leaves the same result.

4. DOption D: It submits data for the server to process and is not idempotent.
   Note on D

   Non-idempotent submission for processing describes POST, the usual verb for creating resources in CRUD.

What is the primary function of the data plane in SDN architecture?

1. AOption A: Forward packets based on rules established by the control plane
   Note on A

   Correct: the data plane forwards packets using the tables that the control plane, or the controller, has built.

2. BOption B: Store configuration data for network devices
   Note on B

   Storing device configuration is a management-plane function.

3. COption C: Make decisions about how traffic should be routed
   Note on C

   Deciding how traffic should be routed is the control plane’s job.

4. DOption D: Provide an interface for applications to request network services
   Note on D

   Offering services to applications is the controller’s northbound API.

Which term describes the architecture where physical network infrastructure carries traffic for multiple isolated virtual networks?

1. AOption A: Spine-leaf network
   Note on A

   Spine-leaf describes a physical topology where each leaf connects to every spine, not virtual networks.

2. BOption B: Mesh network
   Note on B

   Mesh describes how devices are cabled to each other, not virtual networks on top.

3. COption C: Overlay network
   Note on C

   Correct: an overlay builds virtual networks with tunnels such as VXLAN on top of the physical underlay.

4. DOption D: Fabric network
   Note on D

   A fabric is the whole system of underlay plus overlay managed as one, not the virtual networks themselves.

In the context of network automation, what does YANG stand for?

1. AOption A: Yielding Automation Network Grammar
   Note on A

   The name is not built from automation or grammar words; YANG is a data modeling language.

2. BOption B: YAML Automation for Network Generation
   Note on B

   YANG and YAML are unrelated; YAML is a serialization format used by tools such as Ansible.

3. COption C: Year-round Automated Network Gateway
   Note on C

   No gateway is involved; YANG describes data models and is not a device.

4. DOption D: Yet Another Next Generation
   Note on D

   Correct: YANG stands for Yet Another Next Generation, a language that models configuration and state data.

In the context of network automation, which sentence accurately describes the function of REST APIs?

1. AOption A: They enable communication between network devices and network management systems.
   Note on A

   Correct: REST APIs let management systems, controllers and scripts read and change device or controller data over HTTP.

2. BOption B: They use VLAN trunks to segregate network traffic.
   Note on B

   VLAN trunks separate traffic at Layer 2; APIs have nothing to do with tagging.

3. COption C: They are used to discover and manage network topology.
   Note on C

   Topology discovery uses protocols such as CDP and LLDP; an API may expose the result but does not discover it.

4. DOption D: They provide the mechanism for devices to communicate directly with the data plane.
   Note on D

   REST APIs talk to management and control functions; the data plane forwards packets in hardware.

In network automation, what does CRUD stand for?

1. AOption A: Connect, Resolve, Upgrade, Disconnect
   Note on A

   These words describe network tasks, not the four data operations behind CRUD.

2. BOption B: Configure, Restore, Update, Deploy
   Note on B

   Configure and deploy are activities, not part of the create-read-update-delete set.

3. COption C: Control, Routing, Underlying, Device
   Note on C

   This mixes networking terms; CRUD names operations on data.

4. DOption D: Create, Read, Update, Delete
   Note on D

   Correct: Create, Read, Update and Delete map to POST, GET, PUT or PATCH, and DELETE in REST.

Which of the following is NOT typically a benefit of implementing network automation?

1. AOption A: Reduced human error
   Note on A

   Automation applies tested templates the same way every time, which does cut typing mistakes.

2. BOption B: Reduced security requirements
   Note on B

   Correct: automation does not lower security needs; credentials, APIs and tooling must be protected too.

3. COption C: Improved configuration consistency
   Note on C

   Consistency is a main benefit, since every device gets the same configuration.

4. DOption D: Faster network deployments
   Note on D

   Pushing changes by script is much faster than configuring devices one by one.

What HTTP verb would you use to retrieve resource information from a REST API without modifying any data?

1. AOption A: POST
   Note on A

   POST creates a resource or submits data, so it changes state.

2. BOption B: DELETE
   Note on B

   DELETE removes the resource, the opposite of read-only.

3. COption C: GET
   Note on C

   Correct: GET is the safe, read-only verb that returns a resource without changing it.

4. DOption D: PUT
   Note on D

   PUT replaces a resource with new data.

Which aspect of an automation framework primarily focuses on integrating and improving IT infrastructure through continuous delivery and automated testing?

1. AOption A: NetOps
   Note on A

   NetOps refers to network operations work in general, not a delivery practice built on testing pipelines.

2. BOption B: DevOps
   Note on B

   Correct: DevOps joins development and operations through continuous integration, delivery and automated testing.

3. COption C: AIOps
   Note on C

   AIOps applies machine learning to operational data to spot and predict problems.

4. DOption D: SecOps
   Note on D

   SecOps joins security and operations teams; its focus is protection, not delivery pipelines.