A Simple Unified ControlPlane for Packet and Circuit

Networks

Saurav Das, Guru Parulkar, Nick McKeown

Stanford University

2

Motivation

PRODUCTIONRESEARCH

NEEDED: Realistic ways to try out ideas at scale

Many great ideasnone transferred to Production networks

3

New Ideas

• Mobility Management

• Network Security

• Energy Management

• Alternatives to BGP, new routing

• Network Measurement

• Things we haven’t thought of…

Motivation

DeploymentIdea Standardize

Wait 10 years

Exceedingly high barrier to change

• Massive installed base of equipment & protocols – requires backward compatibility

• Rigid nature of platform – closed system, vendor proprietary OS

• Fear of network instability - discourages network operators from innovation - conservatively managed

• Power to control network no longer in SP’s hand

SoftwareControl

Router

HardwareDatapath

20Million linesof source code

5389 RFCsBarrier to entry

500M gates10Gbytes RAM

Bloated Power Hungry( 15 kW/shelf )

We lost our way

Motivation

SoftwareControl

Router

HardwareDatapath

Auth

entica

tion,

Secu

rity, A

ccess

Contro

l

HELLO

6

MPLS

NATIPV6

anycastmulticas

tMobile IP

L3 VPN

L2 VPN VLANOSPF-TE

RSVP-TEHELLOHELLO

Firewall

Multi layer m

ulti

region

iBGP,

eBGP

IPSec

Motivation

Many complex functions baked into the infrastructure

We lost our way

More coming ……

LMP

HELLO

7

UNI

TL-1GMPLS

PBB-TECarrier

EthernetMPLS-TP

ASON

ENNI intra

ENNI inter

OSPF-TE

RSVP-TEHELLOHELLO

CORBA

L1VPN

,

L2VPN

PCE PWE3

Motivation

Lots of baggage from L3

We lost our way

More extensions coming ……

A Clean Slate Approach

8

Goal: Put an Open platform in hands of researchers/students to test new ideas at

scaleApproach:

1. Define OpenFlow feature2. Work with vendors to add OpenFlow to their switches

3. Deploy on college campus networks4. Create experimental open-source software - researchers can build on each other’s work

9

Open Source Networking

What will networks look like in 10 years from now?

10

De-coupling Control & Data Planes

RoutingSignaling

Control

Data

11

Signaling

Control

Data

Controller

De-coupling Control & Data Planes

12

Signaling

Control

Data

Simple, Robust, ReliableData Path

Controller

DecoupledAutomated Control

De-coupling Control & Data Planes

Open Interface

Into Hardware

The Flow Abstraction

Rule(exact & wildcard)

Action Statistics

Rule(exact & wildcard)

Action Statistics

Rule(exact & wildcard)

Action Statistics

Rule(exact & wildcard)

Default Action Statistics

Exploit the flow table in switches, routers, and chipsets

Flow 1.

Flow 2.

Flow 3.

Flow N.

e.g. Port, VLAN ID, L2, L3, L4, …

e.g. unicast, mcast, map-to-queue, drop

Count packets & bytesExpiration time/count

14

Controller

OpenFlow Switch

FlowTableFlowTable

SecureChannelSecureChannel

OpenFlow

Protocol

SSL

hw

sw

http://openflowswitch.org

OpenFlow Switching

• Add/delete flow entry• Encapsulated packets• Controller discovery

A Flow is any combination of above fields described in the Rule

OpenFlow is Backward Compatible

Ethernet Switching

*

SwitchPort

MACsrc

MACdst

Ethtype

VLANID

IPSrc

IPDst

IPProt

TCPsport

TCPdport

Action

* 00:1f:..* * * * * * * port6

Application Firewall

*

SwitchPort

MACsrc

MACdst

Ethtype

VLANID

IPSrc

IPDst

IPProt

TCPsport

TCPdport

Action

* * * * * * * * 22 drop

IP Routing

*

SwitchPort

MACsrc

MACdst

Ethtype

VLANID

IPSrc

IPDst

IPProt

TCPsport

TCPdport

Action

* * * * *5.6.7.8

* * * port6

OpenFlow allows layers to be combined

VLAN + App

*

SwitchPort

MACsrc

MACdst

Ethtype

VLANID

IPSrc

IPDst

IPProt

TCPsport

TCPdport

Action

* * * vlan1 * * * * 80 port6, port7

Flow Switching

port3

SwitchPort

MACsrc

MACdst

Ethtype

VLANID

IPSrc

IPDst

IPProt

TCPsport

TCPdport

Action

00:1f..

0800 vlan11.2.3.4

5.6.7.8

417264

80 port600:2e..

port3

SwitchPort

MACsrc

MACdst

Ethtype

VLANID

IPSrc

IPDst

IPProt

TCPsport

TCPdport

Action

08005.6.7.8

4port 10

00:2e..

Port + Ethernet + IP

* ****

ControllerFlow Example

OpenFlowProtocol

Rule Action Statistics

Rule Action Statistics Rule Action Statistics

A Flow is the fundamentalunit of manipulation within a switch

Routing

OpenFlow Status

Commercial hardwareJuniper, HP, Cisco, NEC, (Broadcom)

Deployed in 3 buildings at Stanford

Deployed in Internet2

Plans for deployment in7 other campuses,

Other RENS – NLR, JGNII, Federica

19

Can we create a way for networking researchers to testtheir ideas at scale…

..in networks that include both packet and circuit switches

20

OpenFlow & Circuit Switches

Exploit the cross-connect table in circuit switches

Packet FlowsSwitc

hPort

MACsrc

MACdst

Ethtype

VLANID

IPSrc

IPDst

IPProt

TCPsport

TCPdport

Action

20

Circuit Flows

Signal Type

VCG20 Signal Type

VCG

Once we have a Flow abstraction,… does it really matter what the underlying switching technology is … packet or circuit?

VCG3

P1 VC4 1 P3 VC4 7

IN OUT

21

TDMCircuitSwitch Fabric

GE ports

TDM ports

Packet Switch Fabric

OpenFlow(software)

Packet Switch Fabric

R A S R A S

IP 10.12.3.4

+VLAN2, P1

VLAN2 VCG 3

OpenFlow(software)

VLAN 1025 +VLAN7, P1

VLAN7 VCG7 VCG7

P1 VC4 4 P2 VC410

Mapping Packet Flows to Circuit Flows

22

Simple Unified Control Plane

FlowNetwork

23

Simple Unified Control Plane

FlowNetwork

… that switch at different granularities: packet, time-slot, lambda & fiber

Packet and Circuit FlowsCommonly Controlled & Managed

Simple,Robust,Reliablenetwork of Flow Switches

Congestion ControlQoS

24

OpenFlow enables innovation

NetworkRecovery

RoutingTraffic

Engineering

PowerMgmt

Security Discove

ry

• Service Provider not handcuffed to the limitations of the platform

• Returns control to the stakeholders of the network

• Open-source networking

Congestion Control

25

Example of what we could try..

TrafficEngineering

26

Example of what we could try..

TrafficEngineering

27

Example of what we could try..

28

Example of others may try..

• All Optical Network control

• New ways to plan and dimension

networks

• Network recovery

• Network discovery

• Power management

• Things we haven’t thought of…

Summary

29

• OpenFlow allows research community to try new ideas at scale

in networks with packet and circuit switches leading to transfer of technology from research to industry – a transfer that barely exists today

• Suggests how networks might be architected in the future

allow new ideas to be tested in one slice before being deployed in the production slice

• We are in the process of convincing circuit switch vendors to add the OpenFlow interface

http://openflowswitch.org