Browse Definitions :
Definition

VXLAN (Virtual Extensible LAN)

Contributor(s): Stan Gibilisco
This definition is part of our Essential Guide: Stay connected with tips and trends in vSphere networking

Virtual Extensible LAN (VXLAN) is a proposed encapsulation protocol for running an overlay network on existing Layer 3 infrastructure. An overlay network is a virtual network that is built on top of existing network Layer 2 and Layer 3 technologies to support elastic compute architectures. VXLAN will make it easier for network engineers to scale out a cloud computing environment while logically isolating cloud apps and tenants.

A cloud computing architecture is by definition, multi-tenant; each tenant requires its own logical network, which in turn, requires its own network identification (network ID). Traditionally, network engineers have used virtual LANs (VLANs) to isolate apps and tenants in a cloud computing environment but VLAN specifications only allow for up to 4,096 network IDs to be assigned at any given time -- which may not be enough addresses for a large cloud computing environment.

The primary goal of VXLAN is to extend the virtual LAN (VLAN) address space by adding a 24-bit segment ID and increasing the number of available IDs to 16 million. The VXLAN segment ID in each frame differentiates individual logical networks so millions of isolated Layer 2 VXLAN networks can co-exist on a common Layer 3 infrastructure. As with VLANs, only virtual machines (VMs) within the same logical network can communicate with each other.

If approved, VXLAN can potentially allow network engineers to migrate virtual machines across long distances and play an important role in a software-defined networking (SDN), an emerging architecture that allows a server or controller to tell network switches where to send packets. In a conventional network, each switch has proprietary software that tells it what to do. In a software-defined network, packet-moving decisions are centralized and network traffic flow can be programmed independently of individual switches and data center gear. To implement SDN using VXLAN, administrators can use existing hardware and software, a feature that makes the technology financially attractive.

This was last updated in October 2012

Continue Reading About VXLAN (Virtual Extensible LAN)

Join the conversation

4 comments

Send me notifications when other members comment.

Please create a username to comment.

Very good explanation of VXLAN. But why 16M segments? With a 12b VLAN ID and a 24b segment ID, shouldn't it provide 64M segments?

Thank you,
Jerry J. Anderson, CCIE #5000
Cancel
It doesn't really add bytes to the VLAN identifier VID, it's a header over the IP level with it's own VXLAN ID named VNI and 24 bytes long.
Cancel
Nice explanation for beginners. Thanks.
Cancel
A new open source tool Ubridge which can be downloaded under sourceforge (inside iptools project) is available for bridge local Windows machine to vxlan. Pls refer to this webpage apps.e5link.com/blog
Cancel

-ADS BY GOOGLE

File Extensions and File Formats

Powered by:

SearchCompliance

  • compliance audit

    A compliance audit is a comprehensive review of an organization's adherence to regulatory guidelines.

  • regulatory compliance

    Regulatory compliance is an organization's adherence to laws, regulations, guidelines and specifications relevant to its business...

  • Whistleblower Protection Act

    The Whistleblower Protection Act of 1989 is a law that protects federal government employees in the United States from ...

SearchSecurity

  • brute force attack

    Brute force (also known as brute force cracking) is a trial and error method used by application programs to decode encrypted ...

  • spyware

    Spyware is software that is installed on a computing device without the user's knowledge. Spyware can be difficult to detect; ...

  • ATM black box attack

    An ATM black box attack, also referred to as jackpotting, is a type of banking-system crime in which the perpetrators bore holes ...

SearchHealthIT

SearchDisasterRecovery

  • business continuity and disaster recovery (BCDR)

    Business continuity and disaster recovery (BCDR) are closely related practices that describe an organization's preparation for ...

  • warm site

    A warm site is a type of facility an organization uses to recover its technology infrastructure when its primary data center goes...

  • disaster recovery (DR) test

    A disaster recovery test (DR test) is the examination of each step in a disaster recovery plan as outlined in an organization's ...

SearchStorage

  • disk array

    A disk array, also called a storage array, is a data storage system used for block-based storage, file-based storage or object ...

  • enterprise storage

    Enterprise storage is a centralized repository for business information that provides common data management, protection and data...

  • optical storage

    Optical storage is any storage type in which data is written and read with a laser. Typically, data is written to optical media, ...

Close