Hi
A virtual network is not a vlan. It is called Virtual Network Overlays. See below info and link:
Network fabric: With a controller element
in place, you can consider building the
network in logical blocks called fabrics.
The Cisco SD-Access Fabric leverages
Virtual Network Overlays in order to
support mobility, segmentation and
programmability at very large scale. The
Virtual Network Overlay leverages a control
plane to maintain the mapping of endpoints to their network location up to date
as end-points move around the network.
Separation of the control plane from the
forwarding plane reduces complexity,
improves scale and convergence over
traditional networking techniques. The
Cisco SD-Access Fabric enables several
key capabilities, such as the host mobility
regardless of volume of moves and size
of the network, Layer 2 and Layer 3
segmentation, and wireless integration.
Other capabilities include intelligent
services for application recognition, traffic
analytics, traffic prioritization and steering
for optimum performance and operational
effectiveness.
https://www.cisco.com/c/dam/en/us/solutions/collateral/enterprise-networks/software-defined-access/solution-overview-c22-739012.pdf
HTH
