16 Software Networks
– precise knowledge of the client and of his/her applications, and
more generally his/her requirements.
2.1.The objective
The objective of SDN (Software-Defined Networking) is to reduce
costs by virtualization, automation and simplification. For this
purpose, SDN facilitates the customization of the networks, a very
short set-up time and a network deployment with the right quality of
service rather than a general quality of service.
The architecture of SDN can be summarized with three
fundamental principles, as shown in Figure 2.1. The first is the
decoupling of the physical and virtual layers (hardware and software).
This enables virtual devices to be loaded on hardware machines. The
network becomes independent of the hardware. This is not completely
realized in reality, because there may be a dependence on the
hypervisor, and certain device manufacturers exploit this point to
force customers to buy their own hardware. The second principle
pertains to the devices connected to the network, which must perceive
no difference between a hardware or software machine. This new
environment enables us to change the network without having to do
anything to the host machines. Finally, the third principle is that of
automation – the best possible automation – of the operations carried
out on the network, whether for management or for control.
The new environments are defined by three domains which
characterize an information- and operation system for a company:
storage, processing and the network. However, in order for the
environment to be able to be executed without problems, we must add
the domains of security and management & control. Today, all five of
these domains need to be in place to constitute a company’s complete
information and operation system. These five domains are shown in
Figure 2.2.
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– precise knowledge of the client and of his/her applications, and
more generally his/her requirements.
2.1.The objective
The objective of SDN (Software-Defined Networking) is to reduce
costs by virtualization, automation and simplification. For this
purpose, SDN facilitates the customization of the networks, a very
short set-up time and a network deployment with the right quality of
service rather than a general quality of service.
The architecture of SDN can be summarized with three
fundamental principles, as shown in Figure 2.1. The first is the
decoupling of the physical and virtual layers (hardware and software).
This enables virtual devices to be loaded on hardware machines. The
network becomes independent of the hardware. This is not completely
realized in reality, because there may be a dependence on the
hypervisor, and certain device manufacturers exploit this point to
force customers to buy their own hardware. The second principle
pertains to the devices connected to the network, which must perceive
no difference between a hardware or software machine. This new
environment enables us to change the network without having to do
anything to the host machines. Finally, the third principle is that of
automation – the best possible automation – of the operations carried
out on the network, whether for management or for control.
The new environments are defined by three domains which
characterize an information- and operation system for a company:
storage, processing and the network. However, in order for the
environment to be able to be executed without problems, we must add
the domains of security and management & control. Today, all five of
these domains need to be in place to constitute a company’s complete
information and operation system. These five domains are shown in
Figure 2.2.
www.it-ebooks.info