Manal Algarni, Vinayak Nair, David Martin, Sayali Shirgaonkar
Project Group Number #1, INFS 612
George Mason University

Research Problem
 Higher consumption of data today via an array of different devices
 No ability to automate for changes at the application and user level
 Software Defined networks (SDN) allows for singular control over a multifaceted network providing a user friendly way to craft data streams
 Our team will present how SDNs works and why they are a superior solution
 How? : Architecture, Protocols and Deployment Models
 Why?: Benefits compared to IP , Use cases for large and small businesses

What are the benefits of SDNs?
 User friendly
 Adaptable
 Real-time changes
 Remote access
 Control of two planes
 Control and data plane
 Decoupling of planes
 Less technical difficulties
 Cost efficient

What are the benefits of traditional IP networks?
 More secure
 Direct access to hardware
 Less easy to hack
 Multiple layers
 Imbedded and resistant to manipulation
 No strict implementation protocol
 Transmission control protocol

Network Planes and Virtualization
 There are four network planes: Control, Forwarding (Data), and
Management
 The Management Plane manages administrative traffic
 Control Plane consists of routing
System configuration, management, and exchange of routing information.

Network Planes and Virtualization
 The Forwarding Plane manages user traffic.
 The Forwarding Plane is only in use at an intermediary router.
 What is Network Virtualization?

Network Planes and Virtualization
 Network virtualization is carving several abstract paths out of a physical network.
 A network virtualization supervisor would describe logical paths through the control plane’s routing information databases.
 The forwarding plane would take direction over packet manipulation and forwarding from a network virtualization supervisor.
 For dynamic management of logical paths, network management software would be required.

SDN Controller
 Interface between applications and network devices
 Contains the control plane after removal from switch
 Programs routing decisions and communicates to network devices using
OpenFlow
 Manages flow control in the network and chooses the optimal path

SDN Protocols – Current Architecture
 Current architecture binds the control plane and forwarding plane
 Control plane creates logic that updates the forwarding plane

SDN Protocols - OpenFlow
 OpenFlow programs the flow table in switches and routers
 Effectively decouples control plane and forwarding plane
 SDN Controller now functions as the control plane

SDN Protocols - OpenFlow
 The Flow table created by OpenFlow is comparable to a CPU Instruction Set
 Three basic options:-
 Forward packet
 Encapsulate and forward to controller
 Drop packet

SDN Deployment Models – 3 approaches
 3 primary deployment models – Switch Based, Overlay, or Hybrid/combination
 1) Switch based – Used for Greenfields where there is no need to consider historical investment in legacy network gear.
 SDN Controller and Label Switched equipment In the enterprise, smart switches designed with application-specific integrated circuits or “ASIC” are sophisticated enough to recognize different types of packets and treat them differently. These ASIC enabled switches are more expensive that existing commodity IP network switches.
 2) Overlay – Uses a tunneling approach, SDN Controller instructs hypervisor switches
 3) Hybrid – Combination of two methods above

Deployment Models – Switch Based
• In this model, the SDN control protocols are issued directly from the SDN controller
(virtual machine) directly to the data control plane within SDN enabled switches and network equipment.
• Drawback does not leverage existing Layer 2/3 network equipment.

Deployment Models – Overlay Model
• The overlay model requires the use of Hypervisor virtual switch equipment that is responsible for providing instructions from the SDN Controller to the existing IP network that run under the virtual switch.
• 2 primary functions within the Vswitch: virtual Ethernet module and virtual supervisor module

Deployment Models - Hybrid
• This deployment is a combination of the switch based and the overlay (tunneling approach) which can be used to gradually migrate existing equipment to a new switch based model.
• Allows for an enterprise to control the speed of its SDN deployment and control the rate of equipment investment (i.e. cost outlays).

SDN Business Case : Large Scale
Implementation
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Business Need
Large scale public cloud providers must contend with service and server mobility
Flexibility to design network polices to respond to peak levels
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SDN Benefits
SDN can direct traffic through the network based on real-time status of all network elements and policies
Use SDN as virtual machines to replace manual device-by-device configuration performed by a large team of network administration personnel.
 The ability to route data over preferred network channels can enable the business to flatten bandwidth consumption which is cheaper than using a dedicated circuit

SDN Business Case : Small Scale
Implementation
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Business Need
Local Campus Networks such as George Mason University’s internal network
Small Business with remote locations
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SDN Benefits
Increases security through OpenFlow which can be programmed to drop unsafe packets
Remote offices will benefit from the SDN automates equipment configuration in common events such as install/adds/moves/changes/ (“IMACs”) and client device roaming.
SDNs allow for central control plane instructions over multiple end-devices, which can strengthen network firewall capabilities.

SDN Consideration Points
 Initial Cost: Depending on the implementation model (switch vs. overlay), new IT hardware to perform the layer 2/3 routing will be required for switch base deployments which are more expensive than traditional IP switches
 Turnover Risk: SDNs as implemented via virtual machines may be perceived as a headcount threat to the Company’s existing network engineering team

Future Works
 Buzz in the industry around SDN. Major players such as Cisco, Juniper have implemented SDN at some level
 We anticipate a major shift over the next few years on how networks are programmed and maintained at a macro scale

Thank You!
 Questions/Comments/Concerns?