NETWORK VIRTUALIZATION class assignment-19BCS092

 

Virtualization has brought a revolution in the world of information technology where no organization can say they haven’t adapted virtualized in theirs. We have learnt about virtual machines, hypervisors, bare metal till now. But will you believe if I say that you can even virtualize routers, switches, load balancers too? You have to.

Let’s learn about network virtualization and how it has really changed the game in the recent years.

Network Virtualization (NV) refers to abstracting network resources that were traditionally delivered in hardware to software. NV can combine multiple physical networks to one virtual, software-based network, or it can divide one physical network into separate, independent virtual networks.

Network virtualization software allows network administrators to move virtual machines across different domains without reconfiguring the network. The software creates a network overlay that can run separate virtual network layers on top of the same physical network fabric.

 

How does network virtualization work?

Network virtualization decouples network services from the underlying hardware and allows virtual provisioning of an entire network. It makes it possible to programmatically create, provision, and manage networks just using software, while continuing to leverage the underlying physical network as the packet-forwarding backplane. Physical network resources, such as switching, routing, firewalling, load balancing, virtual private networks (VPNs) are virtualized without requiring traditional hardware that vendors used to make.

Benefits of network virtualization

·        Simplifies many of the processes that go into running a data center network and managing networking and security in the cloud.

·        Reduce network provisioning time from weeks to minutes

·        Achieve greater operational efficiency by automating manual processes

·        Place and move workloads independently of physical topology

·        Improve network security within the data center

 

Network Virtualization Example

One example of network virtualization is virtual LAN (VLAN). A VLAN is a subsection of a local area network (LAN) created with software that allows to split LANs into multiple, smaller LANs regardless of physical location. VLANs can improve the speed and performance of busy networks and simplify changes or additions to the network.

 

 

 For example, Consider the above diagram. Though the computers belong to a single LAN physically by being connected on the same switch, they are logically or I would say virtually belong to two different VLANs or Virtual LANs. Now the computers in either of the VLANs cannot communicate between VLANs but they can communicate within their own VLANs which provides security and makes network management much easier.

 

Another example is network overlays. There are various overlay technologies. One industry-standard technology is called virtual extensible local area network (VXLAN). VXLAN provides a framework for overlaying virtualized layer 2 networks over layer 3 networks, defining both an encapsulation mechanism and a control plane.

In the above diagram, we have two Layer 3 networks “inet1” and “inet2” connected by two routers. Though they are connected together, they’re still two different domains where one network domain can be different from the other like the routing protocol that each one uses, the STP version they use etc.

But with network virtualization, we create something called “overlay” that differs from “underlay”. This “overlay” is a complete virtualized network where now, it would appear as though the two networks are part of the same network.

This virtualization concept has revolutionized the world of cloud networking!