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Sorting the hype from the truth with intent-based networking systems

Intent-based networking systems could redefine how enterprise networks are managed. But to be successful, these systems must deliver, and not just promise.

For years, network devices were managed by specialized administrators using arcane command-line scripts. These administrators were responsible for the articulation of business needs -- the intent -- translating it into something devices could understand. But this approach, among other inefficiencies, did not scale well, creating bottlenecks that made networks increasingly difficult and costly to manage.

That's because, with scripts, every step must be laboriously articulated in the right order to achieve the desired results. Even with automated tools, today's focus is still technical; the intent -- what the business is trying to do -- is not expressed anywhere other than the admin's head.

Enter intent-based networking systems. IBN brings with it a different vision, through a network of open, programmable devices that can easily be mapped to intent. Ideally, artificial intelligence (AI) or machine learning could then be added to automate the change process.

The goal of an IBN shifts the focus of networks. Instead of coalescing around technology, they focus on the intent. To that end, an IBN relies on GUI-based tools and logic, instead of arcane scripts like this:

int fa0/2

switchport trunk encapsulation dot1q

#switchport mode trunk

switchport trunk allowed vlan add 7


Intent abstracts the technical details, getting to the root of what a business needs to do, like "allow server X to communicate with server Y in a dedicated virtual connection only using a secure protocol."  The intent is then broken down by the system -- without an administrator having to program each device independently -- and articulated by a series of back-end commands to the various devices in the connection route between those two servers. The advent of IBN will change network management in the same way GUI-based operating systems and multitasking changed client computing -- greater productivity and more device abstraction.

Intent-based networking systems: A technology in transition

But for all its benefits, IBN remains a technology in transition. IBN is far from a standard; in fact, most vendors define IBN in their own terms, based on how their products are scoped or behave. Software companies like Apstra and Veriflow were already staking out their claims in this space when the king of network hardware, Cisco, entered with its own definition. Days after the Cisco announcement, Juniper Networks threw its IBN hat in the ring, as well.

While everyone has a different take on defining an IBN, to truly be valuable to customers, IBN needs more than marketing buzzwords or PowerPoint slides; it needs to have some common fundamental characteristics. Chief among them, an IBN must be:

  • Business-focused. The business is not trying to open ports or bind protocols; the business is trying to enable communications between servers or applications. Issuing the statement, "Make cereal for breakfast," is an intent. "Get bowl, get cereal box, open box, tilt box, pour cereal, etc.," are the technical underpinnings that can be abstracted. Let the system, not a human, decide the underlying steps, as many of them are highly repeatable.
  • Vendor-agnostic. Hardware vendors like Cisco have a poor track record here, because they see the world only through their eyes. Intent supersedes vendors; businesses want things done, now. They do not have time to deal with the intricacies or differences between different vendors. Even if a hardware vendor extends its model, the temptation exists to favor its products -- similar to George Orwell's Animal Farm: All products are equal, but some products are more equal than others.
  • Holistic. Treat the network as a single entity. Businesses want a cohesive strategy, not a future where part of their network is intent-based, while part is manually managed. This does not need to be a light-switch transition, but there needs to be a path to 100% coverage.
  • Validated. All change states must be verified and validated, before and after changes. Basically: "Show me the potential impact of what I am going to do, and then verify the actual impact of what I just did."
  • Extensible. Intent-based networking systems need to be flexible, enabling them to extend out and manage any product or technology. Similar to vendor agnosticism, device agnosticism is equally important -- the IBN should have the ability to build a logical model of any current, legacy or future device.
  • Open. In a world of single-vendor networks, a proprietary IBN from a hardware vendor might work, but businesses live in a multivendor world. As a result, an IBN must be open and accessible by other tools and APIs.

Automated networks will still need engineers

If an IBN encompasses these attributes, leveraging both machine learning and AI to autonomously control everything, is the network then self-managing?


If an IBN encompasses these attributes, leveraging both machine learning and AI to autonomously control everything, is the network then self-managing? Hardly.

Network engineers will still need to be involved in setting intent. Today's extra space or missing character in a script can take down a network, but intent-based networking systems have a similar -- but less probable -- vulnerability, as an IBN is only as good as the actual intent. If one means to allow only Secure Sockets Layer traffic through a particular segment, but mistakenly chooses "do not allow" in the GUI, the IBN will do exactly what you instructed, not what you intended. Automation and abstraction reduce this risk significantly, but humans will still be involved. IT teams will spend more time developing business intent, rather than typing configuration scripts.

If the vision of intent-based networks is realized, how will businesses be affected? The change will be felt first with large data centers and cloud providers where the data center is the factory. IBNs will begin as pilots before they extend out across the whole network. SMBs will see IBN deployment much further out, as they typically lack the resources to make the change and the business benefit is not realized as quickly.

That said, IBN's impact is just beginning. Expect this new orchestration and management framework to yield significant benefits, particularly as business move toward a software-defined networking environment.

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This was last published in August 2017

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