Virtual Extensible LAN

Virtual eXtensible LAN (VXLAN) is a network virtualization technology that uses a VLAN-like encapsulation technique to encapsulate OSI layer 2 Ethernet frames within layer 4 UDP datagrams, using 4789 as the default IANA-assigned destination UDP port number,[1] although many implementations that predate the IANA assignment use port 8472.

VXLAN attempts to address the scalability problems associated with large cloud computing deployments.

[3][4] VXLAN is an evolution of efforts to standardize on an overlay encapsulation protocol.

[5] The VXLAN specification was originally created by VMware, Arista Networks and Cisco.

[6][7] VxLAN is widely, but not universally, implemented in commercial networking equipment.