Virtual Extensible LAN

Virtual Extensible LAN (VXLAN) is a network virtualization technology that attempts to address the scalability problems associated with large cloud computing deployments. It 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] VXLAN endpoints, which terminate VXLAN tunnels and may be either virtual or physical switch ports, are known as VXLAN tunnel endpoints (VTEPs).[2][3]

VXLAN is an evolution of efforts to standardize on an overlay encapsulation protocol. It increases scalability up to 16 million logical networks and allows for layer 2 adjacency across IP networks. Multicast or unicast with head-end replication (HER) is used to flood broadcast, unknown unicast, and multicast (BUM) traffic.[4]

The VXLAN specification was originally created by VMware, Arista Networks and Cisco.[5][6] Other backers of the VXLAN technology include Huawei,[7] Broadcom, Citrix, Pica8, Big Switch Networks, Cumulus Networks, Dell EMC, Ericsson, Mellanox,[8] FreeBSD,[9] OpenBSD,[10] Red Hat,[11] Joyent, and Juniper Networks.

VXLAN was officially documented by the IETF in RFC 7348. VXLAN uses the MAC-in-UDP packet encapsulation mode that restricts direct access to some of an object's components.[12]

Open vSwitch is an example of a software-based virtual network switch that supports VXLAN overlay networks.

See alsoEdit


  1. ^ Steve Herrod (August 30, 2011). "Towards Virtualized Networking for the Cloud". VMware. Retrieved 2013-02-25.
  2. ^ Andre Pech (2013-11-08). "Running OpenStack over a VXLAN Fabric" (PDF). pp. 8, 12. Retrieved 2016-07-04.
  3. ^ "Open vSwitch Manual: vtep – hardware_vtep database schema". Retrieved 2016-07-04.
  4. ^ "Arista Expands Leaf Switch Product Portfolio" (Press release). Arista Networks. 22 October 2014. Retrieved 8 November 2014. Arista’s updated VXLAN implementation eliminates the need for multicast in the underlay network by using Head End Replication for forwarding broadcast, multicast and unknown unicast traffic
  5. ^ Timothy Prickett Morgan (30 August 2011). "VMware, Cisco stretch virtual LANs across the heavens". The Register. Retrieved 2013-02-25.
  6. ^ "VXLAN Bridges Virtual and Physical Networks to the Cloud" (PDF). Retrieved 2013-12-01.
  7. ^ "Huawei CE12800 Series Data Center Switches - Huawei products". Huawei. December 2012.
  8. ^ Timothy Pricket Morgan (April 23, 2013). "Mellanox adds VM-flitting to ConnectX-3 adapters - Going Pro with VXLAN". The Register.
  9. ^ "FreeBSD 10.2-RELEASE Release Notes". The FreeBSD Project. The FreeBSD Project. Retrieved 30 June 2016.
  10. ^ Reyk Floeter (October 14, 2013). "OpenBSD vxlan implementation". Reyk Floeter.
  11. ^ M. Mahalingam; et al. (February 22, 2013). "VXLAN: A Framework for Overlaying Virtualized Layer 2 Networks over Layer 3 Networks". Retrieved 2013-02-25.
  12. ^ M. Mahalingam (February 22, 2013). "What Is VXLAN". Huawei. Retrieved 2013-02-25.

External linksEdit