Typically, an organization's network isn't a single thing. It's a collection, a network of networks if you will, which work together to deliver the connectivity from user to app, from sensor to data repository, which underpins application service for an organization.
There are networks of different types, using different technologies, connecting different domains, using multiple vendors; each must be interconnected and interoperable in order to deliver the packets which carry application data from application workload to user. The number and depth of these interactions bring complexity to the network of networks and with it being dynamic and alive, this complexity grows daily.
The biggest challenge that modern network teams face is managing that complexity, along with the scale that adoption of connected applications has brought to the modern IT landscape. And as network engineers, not only are we constantly reminded that the best way to cope is to automate, but we recognize the necessity.
The idea is to maintain a centralized management point for the network which can provision service and deploy change using as few touchpoints as possible. Typically, that might mean introducing:
These approaches all have pros and cons of course, but typically are very focused on delivering an outcome for a specific task, for a specific vendor's equipment, or in a specific network domain. As such, testing of success of automation tends to be focused and task-based too. And while this has a certain level of value in ensuring that tasks themselves aren't broken, it's hard to verify that the impact of change to the network isn't farther reaching, or that further change is required to enable the capability we’re trying to introduce.
Consider the case where you create a new subnet in your private Cloud instance – this is easily verified that it has happened through the API into your favorite Cloud provider. But does that mean it is available and usable? Not necessarily – we might need to make sure it is advertised into our on-prem network, redistributed over our SDWAN into our campus, and that policy is updated to allow traffic to pass to it.
Network Assurance has the goal of validating that the network is operating the way you intend it to and enabling corrective action when your dynamically changing network drifts too far from your intended state. Importantly, the scope for network assurance is the whole network end-to-end, not limited to a specific vendor or domain.
By using IP Fabric's automated network assurance platform, it's possible to validate:
IP Fabric uses snapshots of this model to build up a picture of changes across the network over time. Those snapshots can be of the complete network, scheduled regularly, or they can be ad hoc or partial views, depending on the desired effect (particularly useful before and after change implementation).
And this is the key. When changes are made in the network, it is not likely to be enough to simply test that the desired configuration has been pushed to the device. The impact of that change is likely to be felt further afield and so it is necessary to look more holistically at the outcome, as looking at the change in isolation can be misleading. Is a successful config push successful if it’s impacted your network elsewhere, and therefore your end-to-end service?
You can examine the state of the affected device and that may help but in reality, the best outcome is to validate that once tasks are completed, the overall change has had the desired impact on end-to-end service. And naturally, the only way to accurately verify that end-to-end behavior will be as expected is to not limit the scope but test against a model of the whole network.
And as IP Fabric's API allows snapshot creation and refresh, along with querying of those tests, it is the perfect tool to incorporate into an automated workflow to carry out that big picture validation.
Recently, the IP Fabric team was in Las Vegas, where we shared the stage with Itential at Tech Field Day Extra at Cisco Live 2022. We showcased what it means to integrate network assurance into real network automation processes, and how that turns Network Automation from a point solution to a small problem, into a key component of the complete Self-Driving Network.
Watch the Tech Field Day video below to see exactly how smart integrations can accelerate your network automation: