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Network Functions Virtualization, a new network service model

Network Functions Virtualization, a new network service model

NFV is a solution that brings flexibility and cost savings, enabling network infrastructures to absorb traffic growth and adapt dynamically to service evolutions.


Simplify infrastructures to cut costs and improve quality of service

The complexity associated with a multitude of different networks (2G, 3G, 4G and later 5G) and the extension of the radio spectrum used oblige operators to rationalize and simplify both core network and access network infrastructures. This simplification, referred to as Network Functions Virtualization (NFV), consists in separating hardware infrastructures from software applications and functions.
In short, we will be able to "run" software on standardized hardware in a so-called cloud mode on "Virtual Machines". This changes the network topology (datacenters, points of presence,…) in wireline and cellular networks. Operators will then be able to deliver more services over their networks, and very efficiently since the network will reconfigure itself dynamically in the event of faults. The operator can guarantee availability rates higher than today.


A pragmatic approach

The network transformation has several facets:
- Migration to all-IP: this is in progress and consists in replacing old equipment by IP equipment.
- Virtualization: this has started in the information systems and service platforms and will be extended to all network functions from the core network to the access network.

This virtualization is in fact associated with the arrival of LTE and LTE-A, so it will focus only on these new technologies; 3G and 3G+ infrastructures will remain with the current technology.
NFV can also reduce operating expenses. Energy consumption in particular: virtualization allows network consumption to be managed dynamically. It can direct customers to available technologies in 2G, 3G, 4G… zones, switch off parts of the network at night, and allocate software resources to user groups dynamically as their needs change. If all this is done correctly, networks can be more energy-efficient and deliver better quality of service by supplying capacity to users on demand.


NFV is particularly pertinent for cellular networks

NFV can play a crucial role for three reasons:

  1. It enables a very large number of objects to connect to the network (in the "Internet of Things" the number of connected objects is increasing and causing scalability problems).
  2. It helps manage more finely objects that require only broadband or narrowband Internet access and that consume little energy.
  3. It can manage hybrid networks used by enterprises or consumers. This means that private enterprise network functions can be directly integrated. Finally, we can integrate certain functions in the access network ("distributed cloud") thereby bringing the intelligence as close as possible to connected objects, in the home or the workplace or even on the move.


Virtualization started at Orange

Orange is already in the first stage of virtualizing its core network and service platforms,. At operational level, we need to acquire or develop tools to make best use of NFV.
Our procurement departments are impacted since software purchase is dissociated from equipment purchase. Our vendors will be thinking in terms of opportuneness and risks, spurring them to review their commercial tactics.
Virtualization will be extended later to the mobile access network in which the radio software is highly specialized. In parallel the "centralized RAN" is now being introduced with the objective of being able to manage the software used by several radio sites from a single place. Orange will be able to progressively virtualize by "zones", but this must be accompanied by an increase in access network bandwidth to around 10 Gbps in our various geographic zones.


Do technological innovation and operational performance always go hand in hand?

We are now verifying that virtualization innovations actually generate savings by simplifying operation, cutting energy costs and shortening time to market. The first feedback from service platforms and network core elements is encouraging and several operational trials have been conducted in Europe with good results. The easiest functions to virtualize ─ security, firewalls, customer authentication, gateways ─ will be treated first, progressively as equipment is renewed. Purchases will be made in "virtualized mode" rather than traditional mode.

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