Jen English: virtualization has been around for years. As
enterprises sought more control over their networks. They
started applying virtualization principles to their data
centers, and eventually to the wide area network or WAN and
Local Area Network LAN. Network Virtualization lets enterprises
scale their networks by adding centralized control and applying
specific security policies to workloads and traffic types.
This all helps the network deliver applications and
services more quickly. Here we'll go over the basics of
network virtualization, like how it works, the types and the
benefits and challenges of virtualization. For a deeper
dive explore complete collection on all things network
virtualization, by clicking the link above or in the description
below. Network Virtualization combines the available resources
in a network to consolidate multiple physical networks
divide the network into segments or create software networks
between virtual machines. It abstracts and isolates network
applications and services from the underlying network hardware
devices and physical infrastructure. Teams managing
the network can add in scale these virtual networks without
making any changes to the physical hardware. Because
network virtualization doesn't require admins to manually
configure hardware, teams can spin up logical networks as the
business requires them. This flexibility enables faster
service delivery, operational efficiency and improve control.
Some of the first forms of network virtualization were
virtual private networks or VPNs, and virtual LANs. As
virtualization use cases extended throughout the network
enterprises eventually adopted Software Defined Networking
principles that applied virtualization to their data
centers, WANs and elsewhere. Meanwhile, telecommunications
carriers use feature virtualization and network
virtualization to deliver services efficiently to
enterprise customers. With feature virtualization. The
carrier strategy focuses on Network Functions
Virtualization, or NFV architecture. And if we removed
individual functions like load balancing, routing, and
firewalling, from dedicated hardware devices, and host them
on virtual appliances or commodity hardware. This allows
carriers to load specific feature software onto general
purpose equipment and deliver the services as virtual network
functions or VNFs. If carriers want to expand their portfolios,
they can develop new software instead of buying specialized
hardware. Some common network virtualization use cases include
performance management and security and risk management.
For example, network virtualization helps network
teams allocate appropriate bandwidth for specific
resources, while also specifying and enforcing security policies
to meet auditing requirements. But how exactly does the network
team virtualized network the process typically involves
network components like a network hypervisor, Controller
software, host protocols, virtual switching and routing
and management tools. The key component of abstracting network
services from the physical infrastructure is the network
hypervisor. A hypervisor is a function that isolates operating
systems and applications from the underlying computer
hardware. The hypervisor lets administrators create, provision
and manage virtual networks through software. Admins can
choose to either establish network virtualization
operations manually, or implement them via orchestration
and automation mechanisms. The ladder allows for automated
creation and control of virtual networks. The hypervisor
controls the resources, bandwidth and capacity for each
logical network. While the virtual networks share the
hypervisor platform, they remain independent of each other. They
even have their own security rules. elements within a virtual
network can communicate with each other and with nodes on a
separate virtual network using encapsulated host protocols,
virtual switches, and virtual routers. The messages don't
travel through the physical networking devices, which helps
reduce latency. Network administrators can migrate a
workload from one virtual network host to another in real
time, with the associated security policies and networking
requirements moving with it, the virtualization platform also
apply security policies to new workloads automatically.
Traditionally, virtual networks exist in two forms, external and
internal. These two terms refer to their location in relation to
the server. External virtualization uses switches,
adapters, or networks to combine one or more networks into
virtual units. Internal virtualization uses network like
functionality in software containers on a single network
server. So Virtual Machines can exchange data on a host without
using an external network. Network Virtualization
initiatives are typically identified by their uses within
different segments of the network, such as the data
center, Wan, or LAN. These segments are often managed by
different teams and focus on different use cases. As
networking evolves, though, enterprises may need to consider
how to consolidate these individual initiatives if they
want to attain an end to end network virtualization strategy
with embedded zero trust security. It's probably no
surprise that security must be central to any network design,
but with different areas of the network typically isolated from
one another. It can be difficult for network teams to create and
enforce security policies across the whole network. Taking a zero
trust approach to network security can unify those network
segments and their associated virtualization initiatives. The
zero trust framework relies on user and device authentication
throughout the network. For instance, if users on a LAN
wants to access data center resources, they must receive
authentication to do so. A zero trust environment combined with
network virtualization provides the secure connectivity needed
for endpoints to converse securely. Virtual networks can
be spun up or down to support these interactions, while
maintaining the necessary level of traffic segmentation. But to
ensure the security in the network, it's essential to
specify access policies that detail which devices can talk to
each other and where, for example, if a device is
permitted to reach a data center resource, the policy must also
be set at the WAN and campus levels. This is one of the
biggest challenges for network teams, because it can be
difficult to determine which entities need to talk to each
other. There's a human challenge here, and that's getting teams
to work together. network and security teams need to discuss
security policies, network requirements, and infrastructure
upgrades together. Before we dive into the challenges of
network virtualization, let's look at some of the benefits.
The benefits vary based on the business and where enterprises
implement it within their networks. For example,
virtualization within the data center can support scalability
and enhanced security through micro segmentation. WAN
virtualization, on the other hand, focuses more on improving
application performance and policy enforcement. Overall, the
most common benefits of network virtualization include greater
operational efficiency, faster application delivery, better
network security and disaster recovery, faster network
provisioning and configuration, and hardware cost savings. While
there are clear benefits to network virtualization, it does
come with its challenges. One challenge is virtual sprawl.
Because it's so easy to create virtual networks. Virtual sprawl
happens when admins create more virtual networks than they can
manage or keep track of. Not surprising. This often results
in excess resource consumption and network complexity. Another
challenge is managing the effects of network architecture
changes as enterprises migrate from physical appliances to
virtual networking. They need to calculate how the new
architecture might affect the resource consumption, such as
CPU and storage. A change in network architecture can also
affect resilience and security. Knowledge silos are another
potential headache, traditional IT teams are usually siloed into
different departments, such as security, networking, and
servers. This spread of virtualization throughout
various parts of the network, though, makes collaboration
among these separate departments essential. One of the cultural
challenges is the need for IT staff to quickly acquire new
skills. Because of traditional IT and network silos. There's
going to be a learning curve as IT staff gain the skills they
need to configure, manage and operate various network
virtualization technologies. Then there's the issue of
traditional monitoring tools, losing visibility into the
abstracted layers of the virtual network. To counter this network
teams might adopt more network visibility tools, but that adds
to the sort of tool sprawl that's common among enterprise
networks. Finally, there's a challenge that comes with
automation and AI. Network Virtualization sometimes
introduces automation and AI tools to the network. These
tools improve network management, but they also
require new standards and processes that need to be
documented. Network teams must take care that automation and AI
strategies align with each other. Despite the challenges,
the reality is network virtualization is here to stay.
It will continue to be an important element in both
enterprise and carrier network designs. Moving forward expect
to see network virtualization initiatives That includes zero
trust automation and edge in cloud computing