Final answer:
The technology that creates VXLAN tunnels between SDA switches is an overlay network, which is a virtual network on top of the physical infrastructure, allowing for scalable multi-tenant environments.
Step-by-step explanation:
The technology that creates VXLAN tunnels between SDA (Software-Defined Access) switches is known as an overlay network. An overlay network is a virtual network that is built on top of an existing network infrastructure (the underlay). VXLAN, which stands for Virtual Extensible LAN, operates by encapsulating Ethernet frames within UDP packets, enabling scalable multi-tenant networks over a shared common physical infrastructure.
In the context of Cisco's SDA, the overlay network provides the connectivity between different devices on the network by creating logical tunnels for data transport over the physical underlay network, which handles the actual transport of packets between devices. The tunnels allow for the creation of virtual networks that are independent of the physical network topology and can carry data across various SDA-enabled switches.