SDN (Software-Defined Networking) 21
corresponds to the establishment of the software networks constructed
on the basis of virtual machines, sharing the physical infrastructure in
accordance with the rules deriving from the higher layers. This vision
of the architecture enables us to clearly discern the hardware and the
network which exist in companies from the software, which is added
to offer the necessary flexibility. It is clear that this new architecture
requires more hardware, and therefore the idea is to add datacenters
ranging in size from very small to very large, depending on the size of
the company. Telecoms operators have not missed this opportunity,
and have entered into the market as Cloud providers. Companies such
as Amazon and Google have gone directly for the goal, putting in
place the infrastructure necessary to become major players in the
world of telecommunications.
Figure 2.6. The SDN architecture
In the architecture shown in Figure 2.6, we see the control layer
and the application layer with the northbound and southbound APIs
(Application Programming Interfaces) between those layers, and
the eastbound and westbound APIs with other controllers. The
northbound interface facilitates communication between the
application level and the controller. Its purpose is to describe
the needs of the application and to pass along the commands to
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corresponds to the establishment of the software networks constructed
on the basis of virtual machines, sharing the physical infrastructure in
accordance with the rules deriving from the higher layers. This vision
of the architecture enables us to clearly discern the hardware and the
network which exist in companies from the software, which is added
to offer the necessary flexibility. It is clear that this new architecture
requires more hardware, and therefore the idea is to add datacenters
ranging in size from very small to very large, depending on the size of
the company. Telecoms operators have not missed this opportunity,
and have entered into the market as Cloud providers. Companies such
as Amazon and Google have gone directly for the goal, putting in
place the infrastructure necessary to become major players in the
world of telecommunications.
Figure 2.6. The SDN architecture
In the architecture shown in Figure 2.6, we see the control layer
and the application layer with the northbound and southbound APIs
(Application Programming Interfaces) between those layers, and
the eastbound and westbound APIs with other controllers. The
northbound interface facilitates communication between the
application level and the controller. Its purpose is to describe
the needs of the application and to pass along the commands to
www.it-ebooks.info