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What is Network Virtualization?

Network virtualization is the transforming of a previously hardware-dependent network into a software-based network. Network virtualization, like other kinds of IT virtualization, aims to establish an abstraction layer between physical hardware and the programs and services that utilize that hardware.

Especially, network virtualization enables hardware-independent delivery of network functionalities, hardware resources, and software resources as a virtual network. It can be used to combine many physical networks, partition a single network, or link virtual machines (VMs).

The purpose of network virtualization is to improve network performance, dependability, flexibility, scalability, and security. It is considered to be particularly beneficial in networks that encounter abrupt, unexpected, and substantial use spikes.

Network virtualization functions by combining the available network resources and dividing the available bandwidth into channels, each of which is independent of the others and maybe given (or reassigned) in real-time to a specific server or device. Each channel is secured separately. Each subscriber shares access to the network's resources from a single machine.

As a result of network virtualization, network managers may shift workloads and adjust rules and applications more easily while avoiding difficult and time-consuming reconfigurations. Users benefit from more scalable, dependable, and secure app access in the meanwhile.

What Does Network Virtualization Do?

Network virtualization separates network services from the hardware they run on, allowing a network to be provisioned entirely as a virtual machine. Software-based network provisioning and management is feasible, while still using the underlying physical network as the packet-forwarding backplane, thanks to this technology. Software-delivered pooled physical network resources (such as routing, firewalling, load balancing, and VPNs) require just IP packet forwarding from the underlying physical network to function.

Physical gear such as routers, switches, load balancers, and firewalls are all emulated by network virtualization software. The Open Systems Interconnection Model (OSIM) has numerous levels, including Layer 2 (switches) and Layer 4 (and beyond), which can be virtualized in a network virtualization implementation (load balancers, firewalls, etc.). Administrators can utilize an SD-WAN management tool to keep tabs on the virtual appliances and the entire network, for example.

Through the use of virtualized representations of underlying hardware and software, virtualization software creates a network that functions as a single administrative unit. To cut expenses, the virtualized resources can operate on commercially available x86 off-the-shelf hardware in the form of virtual machines (VMs) or containers.

Virtual networking software guarantees that, in line with already stated policies, the appropriate network services are coupled with each VM- or container-based workload. Service changes may be promptly deployed out to suitable infrastructure without reconfiguration while workloads are dynamically connected to or transported alongside current ones as they move across the network.

As a form of SDN, SD-WAN is also a subtype of network virtualization, as is Network Functions Virtualization (NFV). While NFV is the virtualization of critical operations such as firewalls and load balancing, SDN refers to programmable networks with independent control planes. As for SD-WAN, it is an illustration of the kinds of network overlays that may be achieved by network virtualization.

What is Network Virtualization Types?

External virtualization and internal virtualization are two types of network virtualization. External network virtualization can be used to create independent virtual local area networks (VLANs) from computers that are physically connected to the same local area network (LAN). As a result, service providers are able to boost the productivity of huge networks.

When compared to external network virtualization, internal network virtualization mimics a physical network within a single server. Configuring a server using software containers is a common way to increase a server's operational efficiency. Containers allow for the isolation of individual programs or the running of several operating systems on the same server.

1. Internal Virtualization

It is common to use internal network virtualization in conjunction with hardware and operating system-level virtualization to provide a virtual network interface for the guests. Internal network virtualization can be implemented in a variety of ways: The virtual machine manager can simulate and install an extra network device on the host, along with the driver, or the guest can have a private network that is only accessible by the guest and shares the host's network interface.

It is possible to create an emulated network within a computer's operating system (OS) partition using this kind of networking virtualization. A network-like architecture may be used to connect the guest VMs within an OS partition, either through a shared network interface between the guests and the host or through Network Address Translation. Using internal network virtualization to isolate programs provides an extra layer of protection for your network. It is frequently referred to as a "network-in-a-box" solution by its suppliers.

2. External Virtualization

External Network Virtualization necessitates a physical network device. This form of virtualization has existed for some time; an example would be a CISCO networking switch that offers VLAN (virtual LAN) capabilities via its internal CISCO iOS software. An example of sophisticated CISCO routing is the provision of automated QoS and packet analyzer service, which allows you to prioritize network traffic and detect network-related issues. Due to its "dedicated" character, an external virtualization solution has a very tiny footprint, and its resources are not shared with other duties and obligations of your virtualization infrastructure.

External network virtualization transforms physical systems on the same LAN into distinct VLANs. External networks can also partition several LANs into a single VLAN. The benefit of external networking is increased management efficiency, since IT managers may set up all systems connected to the virtual network as opposed to servicing each unit individually.

What are the Advantages of Network Virtualization?

The vast majority of digital service providers have already committed to network functions virtualization (NFV). NFV is a means to virtualize network functions that have historically been operated on proprietary hardware, such as routers, firewalls, virtual private networks (VPNs), and load balancers. With an NFV approach, these services are packaged as virtual machines (VMs) or containers on commodity hardware, enabling service providers to operate their network on less expensive, ordinary servers.

With these services virtualized, providers may divide network tasks over several servers or relocate them as necessary in response to fluctuating demand. This adaptability expedites network setup, service upgrades, and application delivery without the need for extra hardware resources. The partitioning of workloads into virtual machines (VMs) or containers can help enhance network security.

The benefits of Network Virtualization can be summarized as follows:

  • Simplify data center management: With virtual networks, many functions that would often need on-site management of extra hardware may be delegated to software. And once virtualized, these processes may be automated, which eliminates the complexity and lowers the cost of operating legacy gear.
  • Increase network adaptability: According to business requirements, virtual networks can be created and structured in a variety of ways (e.g., internally or externally). Unlike physical servers, which might take days or weeks to be deployed for new workloads and applications, network virtualization allows for rapid provisioning in reaction to bandwidth surges.
  • Facilitate remote access and efficiency: Employees no longer need to be physically present to access shared apps and storage. By decentralizing office IT, firms may expand their networks and resources to other branches, and employees can remotely access the server over the Internet.
  • Strengthen network security: Virtualized servers can segregate critical data from the data center, protecting it from any cyber attacks, as well as installing virtual firewalls that regulate endpoint access.

What are the Disadvantages of Network Virtualization?

There are certain drawbacks to using network virtualization. The most striking feature is that, like server virtualization, it has the potential to provide more complexity while also increasing performance overhead. The level of expertise required by network administrators and end-users is likewise elevated as a result.

Some of the main disadvantages of network virtualization as follows:

  • Increased initial expenses (investing in virtualization software).
  • The software requires licensing.
  • If IT managers lack experience, there might be a learning curve.
  • In a virtualized environment, not all applications and servers will operate.
  • If a company cannot connect to its virtualized data, there may be issues with availability.