SD-Access Fabric Deployment

SD-Access Fabric Deployment

Below we are going to discuss in detail about SD-Access Fabric deployments model. 

Fabric Deployment Models:

There are multiple deployment options available, however we will explore some of them.

• Fabric Site: A single site configured with SD-Access Fabric Feature.
• Fabric Multi-Site: Multiple Site configured with SD-Access Fabric.

Fabric Site:

A Site is considered to be fabric site, when it as its own set of control plane node, Border nodes, and Edge Nodes.

Following are the key feature of Fabric Site:

• A given IP subnet will be a part of single fabric site.
• L2 mobility and L3 Mobility will be within fabric.
• L2 extension can only be possible with in fabric.
• There will be no context translation necessary within fabric.

Below figure describes the Single fabric site architecture.

A single fabric site can be scaled to large-scale fabric site having multiple horizontal scaled devices or Fabric site in a box where all fabric functions are on single device (Site).

Large Scale Fabric Site:

A large-Scale fabric site extends the single fabric site in such a way that a large number of endpoints can be connected and supported. This can be done by distributing the subnet across a group of control plane and border nodes at site.

Below figure describe large scale fabric site:

Wireless in Large Scale fabric Site:

When a Single site is turned to large scale fabric site, then WLC is also enhanced to support horizontal scale design and WLC is then allowed to communicate to multiple control plane nodes, who is responsible for different IP pools in fabric. But if Wireless infrastructure is also scaling and to achieve it, multiple WLC can be added in same fabric site and is configured in same mobility group to enable seamless roaming.

Fabric Site In-a-Box:

This mode enables border node, edge node, and control plane node function to operate on same fabric device. This enables a very small site also enjoy SD-Access fabric feature and its benefits while maintaining local resiliency and failover mechanism.

Fabric Multi-Site

Many Fabric Sites when interconnected by Transit network Area (this transit network area that has its own control plane nodes, border nodes, but does not have edge nodes). This Transit network area shares atleast one border node from each fabric site that it interconnects.