Good day Huawei family!
A great deal of our esteemed members were kind enough to use our Community to search for information regarding the enterprise network throughout the course of last year and one of the hottest keywords was - surprisingly or not - 'VXLAN'.
Since our pledge for this year is to provide you with more content of your interest, today's blog post will comprise an introduction on VXLAN - an novel network virtualization technology.
BACKGROUND INFORMATION
Virtual eXtensible Local Area Network (VXLAN) is one of the Network Virtualization over Layer 3 (NVO3) technologies defined by the Internet Engineering Task Force (IETF) and is an extension to Virtual Local Area Network (VLAN). VXLAN encapsulates a Layer 2 Ethernet frame into a UDP packet and transmits the packet over a Layer 3 network.
VXLAN is essentially a tunneling technology. It establishes a logical tunnel on the IP network between the source and destination network devices to encapsulate user-side packets and forward them through the tunnel. Servers are connected to different ports of network devices in the data center VXLAN network, which can be considered as a virtual Layer 2 switch.
In a nutshell, VXLAN has become the mainstream technology for constructing data center networks because it can meet the requirements of dynamic virtual machine (VM) migration and multi-tenancy in data center networks.
VLAN VS VXLAN
VLAN is as a traditional network isolation technology. In accordance with standards, a maximum of about 4k VLANs are available, which cannot meet the tenant isolation requirements of large data centers. In addition, each VLAN is a small and fixed Layer 2 virtual network, which does not support large-scale dynamic VM migration
VXLAN overcomes the preceding disadvantages of VLAN. VXLAN uses the 24-bit VNI field to identify up to 16M tenants, compared to a maximum of 4k tenants in VLAN. VXLAN establishes a virtual tunnel between two switches across the basic IP network of the data center and virtualizes the data center network into a large Layer 2 virtual switch to meet the requirements of large-scale dynamic VM migration.
In other words, although VXLAN is an extension to VLAN, VXLAN is quite different from VLAN in terms of virtual tunnel establishment.
CONTEXT OF VXLAN
Why is VXLAN required? This is closely related to the virtualization trend on the server side of the data center. VMs need to be dynamically migrated after server virtualization, requiring an accessible network. As the data center scale increases, the number of tenants increases sharply, requiring isolation of a large number of tenants. VXLAN can meet the two requirements.
TYPES OF VXLAN GATEWAYS
Like in VLANs, hosts in different VNIs and hosts on VXLAN and non-VXLAN networks cannot directly communicate with each other. To meet these communication requirements, VXLAN introduces VXLAN gateways. Two types of VXLAN gateways are available: Layer 2 and Layer 3 gateways.
Layer 2 VXLAN gateways connect terminals to a VXLAN network and enables intra-subnet communication on the same VXLAN network.
Layer 3 VXLAN gateways enable inter-subnet communication on a VXLAN network and external network access.
THE BOTTOM LINE
An innovative technology within the area of network virtualization, VXLAN can undoubtedly come in extremely handy whenever it needs to be employed. More information on VXLAN can be found by accessing this link.
Stay tuned to our daily blog digest by subscribing to the Community blog and don't forget - we're here to help you solve any VXLAN-related issue: https://forum.huawei.com/enterprise/en/WLAN/forum/869.
