Abstract— Massive growth of Internet is leading the world to an
illusion of digital society. Today, everybody is accessible and connected
around the globe using communication networks. One is able to share data,
information and resources with its community now. Traditional IP Networks has
proved very complex and less flexible because of their static nature. These are
hard to maintain and configure using a predefined set of rules and policies. Even
turning the scene more complex, in traditional networks data plane and control
planes are packed in a single package, making software update even much harder.
Software defined networking (SDN) is an emerging field, getting ample research
intention of Networks community 12. SDN promising to de-couple control and
data plane and provide centralize network management. It provides an ability of
program a network as software. SDN provides a paradigm in which network polices
are designed and implemented following separation of concerns. This paper is
aimed to provide a comprehensive survey of Software defined networking,
history, and evolution and research challenges.
Keywords— IP Netwroks,Software Defined
networking, data plane, control plane.
the society is leading to an interconnected set of entities (individuals, cities,
countries etc.). This interconnectivity is because of computer networks. A
typical network is consists of numerous network devices. Some common used
network devices are switches, routers, middle boxes (firewalls) etc 2. These
devices provide foundations to implement complex protocols. To exchange
information accurately and smoothly, functionality of a network is defined into
distributed control and transfer protocols which are implemented on these
communication devices 1. These
networks are consists of two main artifacts:
1. Control plane
2. Data plane.
plane is responsible to define routing and forwarding polices. Whereas, data
plane forward data from hop to hop according to the policies defined b control plane
coupling between data and control plane provide less flexibility and problems
in network updates. It was very problematic to re-organize and re-configure a
network as per predefined set of policies 1.
defined networks (SDN) is new technology, that changed the whole scenario of
networking. In SDNs, the vertical integration of a network is eliminated and
control plane and data plane are separated and implemented on different
devices. Moreover a new concept of centralized control mechanism is introduced
and provided the facility to program a network 1. In this way, separation of
concerns is introduced in network control and forward policies to achieve
desired level of flexibility. It also made possible to easily provide new
abstractions in networks and evolution.
said separation of concern between network control and forward policies is
provided by using well-defined programming paradigm. It provides a stable
interface between network controller and routers. Using application programming
interfaces (APIs), the controller exercise his command authority over all
elements such as routers, switches and middle boxes, in data plane. OpenFlow is
most widely used API 3. Using OpenFlow, a set of rules is created at each
router in from of flow table. While manipulating data traffic (forwarding
packets) , these rules are used to match traffic and perform certain actions
i.e. drop a packet due to violation of rules, forward packet to specified
destination or modify the packet.
OpenFlow switches are equipped with all necessary capabilities to perform all activates
of switching, routing or security (Firewall), under the given instructions by
this paper, a wide-ranging survey of SDN architecture, service model and
application is provided.
History of Programable Netwoks
Openflow is widely used and got a considerable attention in networking
community and industry, the idea of programmable networks is presented many
years age. Various architecture were proposed in past. Some of them are
reviewed in this section.