How to Build an Intent-Based Network (IBN)

With emerging methodologies like Intent-Based Networking (IBN), managing your entire network as a system is becoming easier and more efficient. In this article, we’ll delve into how you can build an IBN in a practical and straightforward manner.

 

What is Intent-Based Networking?

First things first, let’s make sure we understand what IBN is. It is a unified management plane that simplifies network operations by enabling you to control your entire network system through declarative statements. These statements are the ‘intent’ behind the operations, stating what you want to happen, rather than specific (imperative) instructions on how to achieve it.

 

Meta Components of an Intent-Based Network

At the highest level, an Intent-Based Networking (IBN) system requires three foundational “meta” components—intent, state, and actions. Intent refers to the desired outcome or objective that the network should achieve, while state encompasses the current conditions and configurations of the network infrastructure - both boil down to “data.” Actions are the specific tasks or adjustments made to align the network with the defined intent based on the current state. Together, these components create a framework that allows for automated decision-making, optimizing performance and improving the overall user experience.

 

Intent

At the core of IBN lies the concept of ‘intent,’ which acts as the strategic directive for your network. Intent represents the desired outcomes you wish to achieve within your network infrastructure, articulated through high-level, declarative statements. Instead of bogging down in granular details, intent allows network operators to focus on what they want to happen across the network. By abstracting complexity, intent simplifies network management, providing clear objectives that guide network activities.

 

State

The ‘state’ component captures the real-time status of the network, offering a snapshot of current conditions and configurations. It encompasses data collected from various network devices and elements, reflecting how the network is functioning at any given moment. The continuous monitoring and updating of the network state ensure that the actual network performance aligns with the declared intent. This dynamic feedback loop is critical in identifying discrepancies and initiating corrective measures, maintaining the network’s integrity and performance.

 

Actions

‘Actions’ are the operational steps taken to bridge the gap between intent and state. These include not only the automated processes that translate high-level intent into tangible changes within the network but also the critical testing and validation of the network state against the declared intent. By leveraging orchestration and automation tools, actions ensure that necessary adjustments are enacted promptly and accurately, facilitating the desired network performance. This component is vital for adapting to changes, maintaining alignment with the intent, and driving the network towards optimized efficiency.

 

Interrelationship and Importance

The interplay between intent, state, and actions is fundamental to the success of an IBN. Intent sets the strategic direction, state provides the operational reality, and actions are the tactical responses that ensure alignment between the two. Together, they form a cohesive system that enhances decision-making, minimizes manual intervention, and supports a self-correcting network. By understanding and leveraging these components, organizations can achieve a more intelligent and responsive network infrastructure, positioning themselves as leaders in the technological landscape.

 

Key Components of an Intent-Based Network

But how do we make these abstract concepts real? How do we implement them practically? Building an IBN involves several key components:

• Databases and Templates: This component serves as the foundational layer for storing intent and imperative details along with current and historical operational state data. It organizes the information necessary for the system to function, enabling easy storage, retrieval, and management of the data that guides operations.
• Orchestration Engine: The orchestration engine plays a crucial role in ensuring that any changes made in the databases or templates are effectively synchronized with the devices requiring updates. And it ensures that state data is pulled from devices for presentation and validation. It manages the flow of information between the databases and devices to maintain operational consistency. This function coordinates the needed actions, using automation for execution.
• Automation Tools: Automation tools are tasked with executing the actions of pushing changes to devices. They also pull state data from these devices, facilitating real-time updates and maintaining an accurate overview of device statuses within the system. Automation carries out the actions required to maintain intent and state synchronization, as directed by orchestration.
• Network Devices: Network devices (physical and virtual) function as both repositories for (intent and state) data and executors of specific actions. They store necessary information and carry out tasks based on the directives received through automation, ensuring that operations are executed as intended.

 

Implementing an Intent-Based Network

To implement an IBN, you’ll start by defining and/or understanding intent and state, then deriving actions from these. Automation and orchestration play a crucial role in transforming intent into actionable changes within a system. This multi-faceted relationship hinges on understanding how intent drives actions while being informed by the current state of the network.

By closely monitoring the network, we can gather valuable state data, which helps to create a clear picture of the system’s performance. This observability enables us to align actions more precisely with intent, ensuring that responses to changes are both effective and timely. Ultimately, this interplay between intent, state, and actions fosters a more responsive and adaptive environment.

 

Testing and Validation – An Essential Step

Testing and validation play a significant role in the IBN building process. You’ll need to test state against intent to ensure alignment and use validation as a means of verifying configurations.

 

The Crucial Role of APIs

APIs into the orchestration layer allow for programmable interactions and integration with other systems.

Outside teams and tools can harness the power of network orchestration as an automation tool, seamlessly integrating it into their broader operational frameworks. By utilizing APIs, these teams can interact with the orchestration layer, enabling them to programmatically manage network actions.

This integration is crucial for aligning network functions with wider business objectives, such as deploying new services, developing applications, or implementing security protocols. Through this approach, the network becomes a pivotal component of a larger automated system, ensuring that network changes are executed by intent and remain in sync with evolving business needs, all while maintaining a consistent and efficient workflow.

 

Building an IBN in Different Environments

Depending on whether you’re working in a brownfield (existing network) or greenfield (new) environment, your approach will vary:

• Brownfield: In existing networks, the focus is on discovering the existing network infrastructure, which involves assessing current configurations and performance metrics. The goal is to standardize these configurations while ensuring that the network intent aligns with the current operational state. This method allows organizations to optimize and enhance their existing resources without the need for a complete overhaul.
• Greenfield: This strategy involves starting from the ground up, where the network is designed with a clear intent from the outset. It includes creating detailed design templates that account for future scalability and performance needs. By leveraging automation throughout the building process, organizations can streamline deployment, reduce human error, and create a more efficient and effective network tailored to their specific requirements.

You can also use both strategies together, to automate the existing network and new build outs with the same overall system.

 

Practical Steps to IBN Success

The part you’ve been waiting for! As noted above, the process is different for new, greenfield networks and existing, brownfield networks:

 

Greenfield Networks

1. Define Intent and Design: Begin by clearly defining the network’s intent and design in a programmatic manner. Use declarative data to outline desired outcomes and network behavior.

2. Develop Templates: Create network configuration templates that align with the defined intent. Ensure these templates cover all necessary aspects of network functionality across all planned network devices (hardware and software) from the outset.

3. Leverage Automation and Orchestration: Implement automation and orchestration tools from the start to build the network. Use them for the initial configuration onward. This approach helps prevent configuration drift and ensures consistency as the network evolves.

4. Test and Validate: Continuously test and validate the network state against the defined intent. Utilize automated testing tools to ensure the network remains aligned with its original design. Implement event-based automation for no-touch remediation of common issues as your comfort levels rise.

5. Iterate and Adapt: As network requirements change, update the intent and templates. Use the orchestration and automation layers to implement changes efficiently, ensuring the network adapts without manual reconfiguration.

 

Brownfield Networks

1. Ensure Access Homogenization: Verify that there is uniform access to all network devices. Compile an inventory and ensure login capabilities are consistent for both human and machine access.

2. Implement Orchestration and Automation Tools: Incorporate orchestration and automation tools to facilitate ongoing network management. Automate the execution of network actions to ensure intent-driven changes are consistent and efficient. To start, you will use these tools for automated discovery, and then iterative alignment.

3. Conduct Thorough Discovery: Use automated tools to discover and document the current network state. Collect data to understand existing configurations and network behavior.

4. Standardize Configurations: Analyze the collected data to identify inconsistencies and anomalies. Create standardized templates to homogenize configurations and reduce complexity.

5. Align State with Intent: Map the current network state to the intended state. Use the data gathered during discovery to adjust configurations and align them with strategic objectives. This is an iterative process that should leverage your orchestration and automation.

6. Test and Validate: Continuously test and validate the network state against the defined intent. Utilize automated testing tools to ensure the network remains aligned with its original design. Implement event-based automation for no-touch remediation of common issues as your comfort levels rise.

7. Iterate and Adapt: As network requirements change, update the intent and templates. Use the orchestration and automation layers to implement changes efficiently, ensuring the network adapts without manual reconfiguration.

These steps aim to provide a structured approach to building an IBN, tailored to the specific challenges and opportunities of Greenfield and Brownfield environments.

 

Conclusion

Building an intent-based network may seem challenging at first, but by understanding the core components and following these steps, you’ll be well on your way to creating a network that aligns with your intended goals and objectives.

Of course, if it does all seem like too much - FullCtl can help.

Happy Networking!