OpenFlow : Enabling Innovation in Campus Networks SIGCOMM 2008 Nick McKeown, Tom Anderson, et el. Stanford University California, USA Presented by Hyogi Jung 1/17

Contents Internet Closed for Innovations OpenFlow – Goals – Concepts – Architecture – Flow Table Structure – Controller Summary 2/17

Innovations in Legacy Internet Experiments we’d like to do new – Mobility management – Network-wide energy management – New naming/addressing schemes – Network access control Problem with our network – Paths are fixed – IP-only – Addresses dictated by DNS, DHCP, etc – No means to add our own processing 3/17

Why Internet Closed for Innovations? Commercial Vendor won’t open software and hardware development environment – Complexity of support – Market protection and barrier to entry Hard to build my own – Prototypes are unstable – Software only : Too slow – Hardware/Software : Fanout too small (need>100 ports for wiring closet) 4/17

Experimenter’s Dream (Vendor’s Nightmare) 5/17 Standard Network Processing Standard Network Processing hw sw Experimenter writes experimental code on switch/router User- defined Processing User- defined Processing Standard Network Processing Standard Network Processing

OpenFlow’s Goal Put an open platform – researchers/students to test new ideas at scale through production networks – without requiring vendors to expose internal workings Bring Future Internet to legacy Internet An open development environment for all researchers(e.g. Linux, Verilog, etc) 6/17

OpenFlow Concept 7/17 Ethernet Switch Control Path (Software) Data Path (Hardware) Control Path Data Path (Hardware) OpenFlow OpenFlow Controller OpenFlow Protocol (SSL/TCP)

OpenFlow Network Architecture 8/17 Controller OpenFlow Switch Flow Table Flow Table Secure Channel Secure Channel PC OpenFlow Protocol SSL hw sw OpenFlow Switch specification

Operation Step 9/17 Controller PC OpenFlow Switch OpenFlow Switch OpenFlow Switch OpenFlow Switch New function! If header = x, send to port 4 If header =y, overwrite header with z, send to ports 5,6 If header = ?, send to me Flow Table Flow Table Flow Table Flow Table Flow Table Flow Table Flow Table Flow Table

Packet Processing OpenFlow SW’s Packet Processing – Search a matched entry of flow table with arriving packet’s information 10/17 Packet in from Network Flow lookup Send to secure channel Apply actions No match Match

Flow Table Structure Exploit flow table in switches, routers, and chipsets 11/17

Flow Table Entry 12/17 Switch Port Switch Port MAC src MAC src MAC dst MAC dst Eth type Eth type VLAN ID VLAN ID IP Src IP Src IP Dst IP Dst IP Prot IP Prot TCP sport TCP sport TCP dport TCP dport Rule Action Stats 1.Forward packet to port(s) 2.Encapsulate and forward to controller 3.Drop packet 4.Send to normal processing pipeline 1.Forward packet to port(s) 2.Encapsulate and forward to controller 3.Drop packet 4.Send to normal processing pipeline + mask Packet + byte counters

Flow Table Entry Examples (OpenFlow is Backward Compatible) Ethernet Switching IP Routing Application Firewall 13/17 Switch Port Switch Port MAC src MAC src MAC dst MAC dst Eth type Eth type VLAN ID VLAN ID IP Src IP Src IP Dst IP Dst IP Prot IP Prot TCP sport TCP sport TCP dport TCP dport Action * * * * 00:1F:. * * * * * * * * * * * * * * port6 Switch Port Switch Port MAC src MAC src MAC dst MAC dst Eth type Eth type VLAN ID VLAN ID IP Src IP Src IP Dst IP Dst IP Prot IP Prot TCP sport TCP sport TCP dport TCP dport Action * * * * * * * * * * * * * * * * * * port6 Switch Port Switch Port MAC src MAC src MAC dst MAC dst Eth type Eth type VLAN ID VLAN ID IP Src IP Src IP Dst IP Dst IP Prot IP Prot TCP sport TCP sport TCP dport TCP dport Action * * * * * * * * * * * * * * * * * * 22 drop

Flow Table Entry Examples (OpenFlow allows layers to be combined) Flow Switching VLAN + App Port + Ethernet + IP 14/17 Switch Port Switch Port MAC src MAC src MAC dst MAC dst Eth type Eth type VLAN ID VLAN ID IP Src IP Src IP Dst IP Dst IP Prot IP Prot TCP sport TCP sport TCP dport TCP dport Action port3 00:2E:.. 00:1F: vlan port6 Switch Port Switch Port MAC src MAC src MAC dst MAC dst Eth type Eth type VLAN ID VLAN ID IP Src IP Src IP Dst IP Dst IP Prot IP Prot TCP sport TCP sport TCP dport TCP dport Action * * * * * * * * vlan1 * * * * * * * * 80 port6 Switch Port Switch Port MAC src MAC src MAC dst MAC dst Eth type Eth type VLAN ID VLAN ID IP Src IP Src IP Dst IP Dst IP Prot IP Prot TCP sport TCP sport TCP dport TCP dport Action port3 00:2E:.. * * 0800 * * * * * * 22 drop

OpenFlow Controller Centralized Intelligential agency for entire OpenFlow network NOX is an open-source OpenFlow Controller Researchers can insert their software code into NOX controller for testing their idea 15/17 Nox Controller OpenFlow Switch

OpenFlow Hardware (Switches) 16/17 NEC HP Pronto

Summary OpenFlow – Standard way to control flow-tables in commercial switches and routers – Put an open platform – An open development environment for all researcher – Test Environment for Future Internet Technologies 17/17