introduction to openflow -...

© 2013 Cisco and/or its affiliates. All rights reserved. 1

Introduction to OpenFlowPresented by:Shangxin Du – TAC DC Solution

20 April, 2015


Forget everything you know about:

• Transparent Bridging

• STP

• L2 Forwarding

• IP Routing

• L3 Forwarding

• And so on …

© 2013 Cisco and/or its affiliates. All rights reserved. Cisco Public 3

Open Networking Foundation


• Control plane is decoupled from data plane; centralized and given span of control over multiple data plane switch elements

• Controller manages switch flow table using OpenFlow protocol

Add, update, delete flow entries, both reactively and proactively

I/O Module (Line Card)

OpenFlow Controller






DPID:0001000573ff61e0DPID:0001000573ff58e0

OpenFlow Protocol



• Traditional captive control plane/data plane components co-exist with OpenFlow Switch capabilities

• OpenFlow defines logical “ports” for passing packets to traditional and OpenFlow pipelines

Supervisor



OpenFlow Controller

Hybrid Switch A

OF Agent


Supervisor



Hybrid Switch A

OF Agent

OpenFlow Protocol

© 2013 Cisco and/or its affiliates. All rights reserved. 6 6

Controller port

Physical Port

Logical Port

(representing link bundle)

LOCAL “Port”

NORMAL “Port”

Flow Tables

Normal

Switch

stage

Logical Port (representing a VLAN)OpenFlow

Switch

stage

Log. Port (Tunnel)

Logical Port (representing a VLAN)


• Each OpenFlow Switch has a single flow table, which is used for packet lookup and forwarding

• Packets not matching an entry in the flow table are punted to the controller

flow 0

flow 1

flow 2

flow 3

flow 4

flow 5

Table N


• A flow table consists of one or more flow entries

• Each entry consists of one row in the flow table

flow 0

flow 1

flow 2

flow 3

flow 4

flow 5

Table N

• match fields: ingress port + packet headers

• priority: precedence of the flow entry

• counters: updated for each matching packet

• timeouts: maximum amount of time or idle time before flow entry expires

• action(s): one or more actions to take on match packets

• cookie: opaque data chosen by controller

Match Fields Priority Counters Timeouts CookieAction(s)


Flow Table in more detail…

FLOW TABLE

HEADER FIELDS COUNTERS ACTIONS

…

…

… …

… …

Ingress

Port

Source

MAC

Dest

MAC

Ether

Type

VLAN

IDVLANPriority

IP

SRC

IP

DEST

IP

Proto

IP

TOS

TCP/

UDP

SRC

TCP/

UDP

DEST

OF1.0 HEADER FIELDS

This is the “Famous” OpenFlow 12 Tuple

1 2 3 4 5 6 7 8 9 10 11 12


Data Data Data

Sw

itch

FLOW

TABLE

SWITCH FORWARDING

ENGINE

OPENFLOW CONTROLLER

** CPU

**OpenFlow 1.0 supports a lookup into a single flow table


Data Data Data

FLOW

TABLE

SWITCH FORWARDING

ENGINE

CPU

Lookup Key

Header fields used to build lookup key

Sw

itc

h


Sw

itc

h

FLOW

TABLE

SWITCH FORWARDING

ENGINE

OPENFLOW CONTROLLER

CPU

Data Data Data

If no match, Controller may

receive packet and program

the flow table


Data Data

Sw

itc

h

FLOW

TABLE

SWITCH FORWARDING

ENGINE

OPENFLOW CONTROLLER

Forwarding Engine forwards packets

CPU


FLOW TABLE

HEADER FIELDS COUNTERS ACTIONS

…

…

… …

… …

Several important OF1.0 Actions

Let us explore in more detail…


Sw

itch

FLOW

TABLE

SWITCH

FORWARDING

ENGINE

OPENFLOW

CONTROLLER

CPU

1

Packet


Sw

itch

FLOW

TABLE

SWITCH

FORWARDING

ENGINE

OPENFLOW

CONTROLLER

CPU

Packet

2


Sw

itch

FLOW

TABLE

SWITCH

FORWARDING

ENGINE

OPENFLOW

CONTROLLER

CPU

Packet

3


Sw

itch

FLOW

TABLE

SWITCH

FORWARDING

ENGINE

OPENFLOW

CONTROLLER

CPU

Packet4


Sw

itch

FLOW

TABLE

SWITCH

FORWARDING

ENGINE

OPENFLOW

CONTROLLER

CPU

5Packet


Sw

itch

FLOW

TABLE

SWITCH

FORWARDING

ENGINE

OPENFLOW

CONTROLLER

CPU

Packet

6


Sw

itch

FLOW

TABLE

SWITCH

FORWARDING

ENGINE

OPENFLOW

CONTROLLER

CPU

Packet

7


Sw

itch

FLOW

TABLE

SWITCH

FORWARDING

ENGINE

OPENFLOW

CONTROLLER

CPU

Packet

8


FLOW

TABLE

SWITCH

FORWARDING

ENGINE

OPENFLOW

CONTROLLER

7

2

8

CPU

1

45

6

Important Actions

1 Forward to all ports

except input

2 Redirect to Controller

3 Output from Controller

4 Forward to local CPU

5 Rewrite Packet Header

6 Forward to input port

7 Forward to dest port

8 Drop packet

3


Dec 2009

OF 1.0

Feb 2011

OF 1.1

• Single flow

Table

• L2, IPv4

focused

matching

• Basic actions

• Multiple flow tables

• Group table

• Packet processing

options

• MPLS

• VLAN


Dec 2009

OF 1.0

Feb 2011

OF 1.1 OF 1.2

Dec 2011

• Single flow

Table

• L2, IPv4

focused

matching

• Basic actions

• Group table

• Multiple flow

tables

• Packet

Processing

Options

• MPLS, VLAN

• IPv6

• Extensible

matching


Dec 2009

OF 1.0

Feb 2011

OF 1.1 OF 1.2 OF 1.3.0

Dec 2011 Apr 2012

• Single flow

Table

• L2, IPv4

focused

matching

• Basic actions

• Group table

• Multiple flow

tables

• Packet

Processing

Options

• MPLS, VLAN

• IPv6

• Extensible

matching

• IPv6 Extended Headers

• Meter table

• Auxiliary Connections

• Advanced MPLS

• PBB

• Version negotiation

• Controller connections

OF 1.3.1

(stability)

Sep 2012 Apr 2013

OF 1.3.2


OF 1.0

stability

Cisco

OF 1.1 OF 1.2 OF 1.3

stability

Cisco

• Table sync

• Non-Ethernet

• Flow monitoring

• Generic

tunnels

• “Split brain”

OF 1.4

Aug 2013 in progress

OF 1.5


C, JAVA Program

onePK API Presentation

onePK API Infrastructure

IOS / XE

(Catalyst, ISR,

ASR1K)

NX-OS

(Nexus Platforms)

IOS-XR

(ASR 9K, CRS)


Application -> OpenFlow Agent

onePK API Presentation -> Native NOS and Container

onePK API Infrastructure -> Native NOS

IOS / XE

(Catalyst)

NX-OS

(Nexus Platforms)

IOS XR

(ASR 9K)


IOS / XE NX-OS IOS-XR

onePK API Infrastructure

Application Framework / XNC Controller

onePK SDK

Applications

Network Device

onePK transport

OpenFlow

OpenFlow

Agent

OpenFlow 1.0/1.3


OF Switch 30

OF Switch 10

OF Switch 20

Supervisor OF Agent

OpenFlow Controller

OpenFlow Controller

CID=10

CID=20

CID=30


Pure OpenFlow* Ships in the Night Integrated

• All ports are OpenFlow only

• All forwarding decisions by Controller

• Example: Network Monitoring

* There still may be some non OpenFlow ports for connecting to management device or initial setup

• OF co-exists with normal forwarding

• Port segregation

• No traffic flow between domains

• Example:Network Slicing

• Packet may traverse OpenFlowpipeline and normal pipeline

• Output to NORMAL and Logical ports

• Example: Traffic Steering


Visibility Tools Production Network

Wireshark

Video

Monitor

SPAN Ports

Dynamic Filter and

Forwarding Event

Driven / Real Time

Replaces Matrix Network withNexus 3000s, Controller, and Monitor Manager App

With XNC Monitor Manager Solution

OpenFlow

Enabled

Nexus 3000s

Java and

RESTful

NEW CUSTOM

TOOLS

Extensible

Network

Controller


Objective: Establish a flow

to bypass the

firewall for

trusted traffic

to improve

application

performance

Firewall Trusted Flow Acceleration

Trusted Flow Path

Accelerated Flows and “Science DMZ” Slice

External Resourcesor Networks

Controller


Transit Selection: Network Parameter Driven (Latency)

2 ms

OpenFlow / onePK

Cisco XNC

Controller

Other Transit Selection Parameters Also Possible


Site 1 / Branch Site 2 / DC

Transit Selection

MPLS

PUBLIC

CAMPUS /

INTERNAL

Cisco XNC

Controller

Control egress path based on application requirement and prioritySimple forwarding rules help improve WAN utilization


SDN Application

XNC ControllerPCE (Cariden)

Existing

Functionality

New Functionality

15

4

2

State Report

Traffic steering Path Request from Application

Tunnel Create

Request

MPLS-TE LSP

RSVP

Signaling

3

Traffic Engineering with PCE and OpenFlow


• A Linux Foundation Project

• Industry-Supported

Thank you.

introduction to openflow -...

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