SDN most commonly means that networks are controlled by software applications and SDN controllers rather than the traditional network management consoles and commands that required a lot of administrative overhead and could be tedious to manage on a large scale “What is SDN? The physical separation of the network control plane from the forwarding plane, and where a control plane controls several devices.”

1. Software Defined network
By:
Aadarsh Sharma (152401)
Nitesh Sharma (152409)
ME CSE Regular 2015

2. • SDN most commonly means that networks are
controlled by software applications and SDN
controllers rather than the traditional network
management consoles and commands that required a
lot of administrative overhead and could be tedious to
manage on a large scale.
• SDN is a framework to allow network administrators to
automatically and dynamically manage and control a
large number of network devices, services using high-
level languages and APIs.
• SDN is to enable cloud and network engineers to
respond quickly to changing business requirements
via centralized control console.
What’s SDN ?

4. A Short History of SDN
~2004: Research on new management paradigms
RCP, 4D [Princeton, CMU,….]
SANE, Ethane [Stanford/Berkeley]
2008: Software-Defined Networking (SDN)
NOX Network Operating System [Nicira]
OpenFlow switch interface [Stanford/Nicira]
2011: Open Networking Foundation (~69 members)
Board: Google, Yahoo, Verizon, DT, Microsoft, Facebook, NTT
Members: Cisco, Juniper, HP, Dell, Broadcom, IBM,…..
2013: Latest Open Networking Summit
1600 attendees, Google: SDN used for their WAN
Commercialized, in production use (few places)
4

5. • Traditional networking architectures have significant
limitations that must be overcome to meet modern IT
requirements. Today’s network must scale to
accommodate increased workloads with greater
agility, while also keeping costs at a minimum. But the
traditional approach has substantial limitations:
• Complexity
• Inconsistent policies
• Inability to scale
Why SDN ?

6. • The abundance of networking protocols and features
for specific use cases has greatly increased network
complexity. Old technologies were often recycled as
quick fixes to address new business requirements.
Features tended to be vendor specific or were
implemented through proprietary commands.
Complexity:

7. • Security and quality‐of‐service (QoS) policies in
current networks need to be manually configured or
scripted across hundreds or thousands of network
devices. This requirement makes policy changes
extremely complicated for organizations to implement
without significant investment in scripting language
skills or tools that can automate configuration
changes.
• Manual configuration is prone to error and can lead to
many hours of troubleshooting to discover which line
of a security policy or access control list (ACL) was
entered incorrectly on a given device.
Inconsistent policies:

8. • As application workloads change and demand for
network bandwidth increases, the IT department either
needs to be satisfied with an oversubscribed static
network or needs to grow with the demands of the
organization.
Inability to scale:

9. • “What is SDN? The physical separation of the network
control plane from the forwarding plane, and where
a control plane controls several devices.”
Original Defination

10. • Makes decisions about where traffic is sent
• Control plane packets are destined to or locally originated
by the router itself
• The control plane functions include the system
configuration, management, and exchange of routing table
information
• The route controller exchanges the topology information
with other routers and constructs a routing table based on a
routing protocol, for example, RIP, OSPF or BGP
• Control plane packets are processed by the router to
update the routing table information.
• It is the Signaling of the network
Control Plane

11. • Also known as Forwarding Plane
• Forwards traffic to the next hop along the path to the
selected destination network according to control
plane logic
• Data plane packets go through the router
• The routers/switches use what the control plane built
to dispose of incoming and outgoing frames and
packets
Data Plane

13. • An SDN controller is the centralized repository of
policy and control instructions for the network or
application infrastructure.
• The controller bridges the gap between open,
programmable network elements and the applications
that communicate with them, automating the
provisioning (the setup and management) of the entire
infrastructure, including the network, services, and
applications.
• The controller gives you a programmatic interface for
setting policies andprovisioning services across your
network.
SDN Controllers

15. • Virtualization: Use network resource without worrying
about where it is physically located, how much it is, how it is
organized, etc.
• Orchestration: Should be able to control and manage
thousands of devices with one command.
• Programmable: Should be able to change behavior on the
fly.
• Dynamic Scaling: Should be able to change size, quantity
• Automation: To lower & minimize manual involvement
– Troubleshooting
– Reduce downtime
– Policy enforcement
Features

16. SDN Architecture

17. SDN Layers

22. SDN potential use Cases