Transcript Slides - George Mason University

Software Defined Networking
Overview and Implementation
Manal Algarni, Vinayak Nair, David Martin, Sayali Shirgaonkar
Project Group Number #1, INFS 612
George Mason University
Research Problem
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Higher consumption of data today via an array of different devices
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No ability to automate for changes at the application and user level
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Software Defined networks (SDN) allows for singular control over a
multifaceted network providing a user friendly way to craft data streams
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Our team will present how SDNs works and why they are a superior solution
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How? : Architecture, Protocols and Deployment Models
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Why?: Benefits compared to IP , Use cases for large and small businesses
What are the benefits of SDNs?
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User friendly
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Adaptable
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Real-time changes
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Remote access
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Control of two planes
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Control and data plane
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Decoupling of planes
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Less technical difficulties
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Cost efficient
What are the benefits of traditional IP
networks?
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More secure
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Direct access to hardware
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Less easy to hack
Multiple layers
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Imbedded and resistant to manipulation
No strict implementation protocol
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Transmission control protocol
Network Planes and Virtualization
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There are four network planes: Control, Forwarding (Data), and
Management
The Management Plane manages
administrative traffic
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Control Plane consists of routing
System configuration, management,
and exchange of routing information.
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Network Planes and Virtualization
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The Forwarding Plane manages user traffic.
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The Forwarding Plane is only in use at an intermediary router.
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What is Network Virtualization?
Network Planes and Virtualization
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Network virtualization is carving several abstract paths out of a physical
network.
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A network virtualization supervisor would describe logical paths through
the control plane’s routing information databases.
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The forwarding plane would take direction over packet manipulation and
forwarding from a network virtualization supervisor.
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For dynamic management of logical paths, network management software
would be required.
SDN Controller
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Interface between applications and network devices
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Contains the control plane after removal from switch
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Programs routing decisions and communicates to network devices using
OpenFlow
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Manages flow control in the network and chooses the optimal path
SDN Protocols – Current Architecture
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Current architecture binds the control plane and forwarding plane
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Control plane creates logic that updates the forwarding plane
SDN Protocols - OpenFlow
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OpenFlow programs the flow table in switches and routers
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Effectively decouples control plane and forwarding plane
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SDN Controller now functions as the control plane
SDN Protocols - OpenFlow
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The Flow table created by OpenFlow is comparable to a CPU Instruction Set
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Three basic options:
Forward packet
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Encapsulate and forward to controller
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Drop packet
SDN Deployment Models – 3 approaches
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3 primary deployment models – Switch Based, Overlay, or Hybrid/combination
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1) Switch based – Used for Greenfields where there is no need to consider historical
investment in legacy network gear.
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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.
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2) Overlay – Uses a tunneling approach, SDN Controller instructs hypervisor switches
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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
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Large scale public cloud providers must contend with service and server mobility
Flexibility to design network polices to respond to peak levels
SDN Benefits
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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
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Local Campus Networks such as George Mason University’s internal network
Small Business with remote locations
SDN Benefits
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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
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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
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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
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Buzz in the industry around SDN. Major players such as Cisco, Juniper have
implemented SDN at some level
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We anticipate a major shift over the next few years on how networks are
programmed and maintained at a macro scale
Thank You!
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Questions/Comments/Concerns?