Using OpenFlow and Orbit to Achieve Mobility in a Heterogeneous Wireless Network Ryan Izard rizard@g.clemson.edu GREE-SC2014 Iowa State University Sponsored by the National Science Foundation Outline 1. A brief overview of software defined networking (SDN) and OpenFlow (OF) 2. OF controller and OF switch software components and interaction 3. The Floodlight (FL) OF controller 4. Achieving IP Mobility with OF 5. Tutorial / Walk-through Sponsored by the National Science Foundation GREESC2014 2 What is Software Defined Networking and OpenFlow? Sponsored by the National Science Foundation GREESC2014 3 What is SDN? • Physical separation of network control plane from forwarding/data plane • Network control – Centrally managed – Directly programmable • Network infrastructure – Abstracted from applications Sponsored by the National Science Foundation GREESC2014 4 How Does SDN Work? API Feature A API Feature B API Feature C Network Operating System Packet Forwarding Packet Forwarding Packet Forwarding Packet Forwarding Packet Forwarding Sponsored by the National Science Foundation GREESC2014 5 What Is OpenFlow? • Link between SDN control and infrastructure layers • OF-enabled infrastructure communicates with an OF controller via the OF protocol Sponsored by the National Science Foundation GREESC2014 6 How Does OF Work? User Applications Network Services Custom Services APIs OpenFlow Controller Packet Forwarding Packet Forwarding Packet Forwarding Packet Forwarding Packet Forwarding Sponsored by the National Science Foundation GREESC2014 7 Basic SDN packet handling example Sponsored by the National Science Foundation GREESC2014 8 Basic SDN packet handling example User 1 Sponsored by the National Science Foundation User 2 GREESC2014 9 Basic SDN packet handling example User 1 Sponsored by the National Science Foundation User 2 GREESC2014 10 OpenFlow Switches and Controllers Sponsored by the National Science Foundation GREESC2014 11 time Bottom-Up: An OF-Enabled Switch 1. Power On 2. Bootloader 3. OF-Enabled OS Control Path OpenFlow Data Path / Switching Hardware Flow Table Sponsored by the National Science Foundation GREESC2014 12 OF Switch Connection to Controller Network Services Custom Services APIs OpenFlow Controller (e.g. Floodlight, NOX, etc.) OS (e.g. Linux, Mac, Windows, etc.) Hardware Control Path OpenFlow Data Path / Switching Hardware Flow Table Sponsored by the National Science Foundation GREESC2014 13 OF Switch Connection to Controller • Switch probes for controller – Configured with controller IP/port (6633/6653) – Connection established via TCP/TLS – Standalone or secure modes • Controller can learn topology – Packet-out LLDP – Devices and other participating OF switches discovered and mapped Sponsored by the National Science Foundation GREESC2014 14 Application Connection to Controller Application Requesting Controller Service(s) Interface to Controller (e.g. REST) OS (e.g. Linux, Mac, Windows, etc.) Hardware Network Services Custom Services APIs OpenFlow Controller (e.g. Floodlight, NOX, etc.) OS (e.g. Linux, Mac, Windows, etc.) Hardware Sponsored by the National Science Foundation GREESC2014 15 Application Connection to Controller • Controller-dependent • Floodlight provides REST API – JSON – Modify or query running configuration – Expandable with custom modules • Options are vast with open-source – Customize controller APIs and behavior – User-application-independent (e.g. a transparent network service like SOS) Sponsored by the National Science Foundation GREESC2014 16 The Floodlight OpenFlow Controller • Open-source OF controller • Sponsored and supported by Big Switch Networks • Written in Java and easily used with Eclipse • Modifiable and expandable to suit any application via modules • Large developer community and support group Sponsored by the National Science Foundation GREESC2014 17 Floodlight Modules • What is a Floodlight (FL) module? – FL service that reacts to switch/controller events, manages running switches, and/or manages controller configuration – Java package – FL ships with many modules, but custom modules are supported • Modules can work collaboratively and be chained to achieve desired results Sponsored by the National Science Foundation GREESC2014 18 time Floodlight Architecture 1. 2. 3. 4. 5. Execute Parse module list Load modules Start REST service Start FL Provider Service (Core) FL Modules (e.g. Forwarding, DHCP, Your_Module, etc.) FL Provider Service Sponsored by the National Science Foundation GREESC2014 REST Service 19 Floodlight Architecture Sponsored by the National Science Foundation GREESC2014 20 Customizing Floodlight Behavior • Off-the-shelf, the FL controller mimics traditional learning switch behavior for all connected switches • Custom modules allow for advanced SDN applications/behaviors – SOS, HetNet Mobility, GENI Cinema, etc. – Add your custom modules here too! • REST API allows third party apps to query and modify the running configuration of FL Sponsored by the National Science Foundation GREESC2014 21 How can Software Defined Networking and OpenFlow be Used to Achieve a Vertical Handover? Sponsored by the National Science Foundation GREESC2014 22 • Part I: Design/Setup – Use OpenFlow to perform L2 handoff • Part II: Execute – Configure and initialize software and scripts – Execute handoff experiment • Part III: Finish – Determine results – Kill processes – Shutdown node and logout Sponsored by the National Science Foundation GREESC2014 23 Mobility Over Heterogeneous Networks • Provide mobility for clients over IPv4 • Entirely SDN and OF-based solution – Network-level • Migration detection • IP address assignment and management • Packet routing – Client-level • Packet routing • Interface switching • Transparent service to application Sponsored by the National Science Foundation GREESC2014 24 Mobility Over Heterogeneous Networks • Network-Level, Mobile IP: – Home/Foreign Agents OpenFlow Controller – Mobile IP tunnels OpenFlow flows – DHCP server on OpenFlow controller • Client-Level, Vertical Handoff: – Change physical interface broken socket – Open vSwitch + Floodlight OF controller • Manage the physical interfaces via SDN • End-user sees “always-up” virtual interface Sponsored by the National Science Foundation GREESC2014 25 Client Connects to WiMAX Client-Level Sponsored by the National Science Foundation GREESC2014 26 Client Connects to WiMAX Network-Level Sponsored by the National Science Foundation GREESC2014 27 Client Uses WiMAX Network Network-Level Sponsored by the National Science Foundation GREESC2014 28 Client Migrates Network-Level Sponsored by the National Science Foundation GREESC2014 29 Client Switches to WiFi Interface Client-Level Sponsored by the National Science Foundation GREESC2014 30 Network Responds to Handover Network-Level Sponsored by the National Science Foundation GREESC2014 31 Client Connection Rerouted to WiFi Network-Level Sponsored by the National Science Foundation GREESC2014 32 Client-Level Sponsored by the National Science Foundation Mobility Over Heterogeneous Networks GREESC2014 33 Sponsored by the National Science Foundation GREESC2014 34 Sponsored by the National Science Foundation GREESC2014 35 • Part I: Design/Setup – Use OpenFlow to perform L2 handoff • Part II: Execute – Configure and initialize software and scripts – Execute handoff experiment • Part III: Finish – Determine results – Kill processes – Shutdown node and logout Sponsored by the National Science Foundation GREESC2014 36 Configure Experiment • Experiment is a simple ping to demonstrate a vertical handoff between a WiFi and a WiMAX interface on a node in the Orbit grid testbed • Detailed instructions: – http://groups.geni.net/geni/wiki/GENIExperimenter/Tutorials/ WiMAXOpenFlow • GREE-SC2014 group and node assignments: – http://tinyurl.com/greesc2014-d7-node-info Sponsored by the National Science Foundation GREESC2014 37 Configure Experiment • Enable WiMAX for your GENI project – – – – – Login to GENI at portal.geni.net Scroll down to the Tools section and select WiMAX Select the button to enable WiMAX for your project (GREESC14) Click Submit Note your username Sponsored by the National Science Foundation GREESC2014 38 Configure Experiment • You should be able to login to the Orbit testbed for your project – eval `ssh-agent –s` – ssh-add /path/to/private/key • Open two separate terminal windows and in each SSH to Orbit – ssh username@console.grid.orbit-lab.org Sponsored by the National Science Foundation GREESC2014 39 Configure Experiment • Load AP image onto node – omf load -o 1200 -i rizard-greesc2014ap.ndz -t node11-11 • Load Server image onto node – omf load -o 1200 -i rizard-greesc2014server.ndz -t node10-10 • Load Client image onto node – omf load -o 1200 -i rizard-greesc2014client.ndz -t <client-node> • Power off and boot nodes – omf tell -a offh -t node11-11,node1010,<client-node> – omf tell -a on -t node11-11,node1010,<client-node> Sponsored by the National Science Foundation GREESC2014 40 Configure Experiment • Setup AP node (Already done for GREE-SC2014) – ssh root@node11-11 – Start: ./gec20_setup_ap.sh • Setup Server node (Already done for GREE-SC2014) – ssh root@node10-10 – Start: ./StartupScripts/gec20_setup.sh – ARP: ./StartupScripts/arp_add_list.sh • Setup Client node – Your Turn! – ssh root@<client-node> – Disable Floodlight’s forwarding module – Configure startup and switching scripts – Start: ./StartupScripts/gec20_setup.sh Sponsored by the National Science Foundation GREESC2014 41 • Part I: Design/Setup – Use OpenFlow to perform L2 handoff • Part II: Execute – Configure and initialize software and scripts – Execute handoff experiment • Part III: Finish – Determine results – Kill processes – Shutdown node and logout Sponsored by the National Science Foundation GREESC2014 42 Execute Experiment 1) WiFi flows are installed as “initial flows” when setup script is run. 2) In a new terminal, start a ping to the server IP, 10.41.105.105. The packets will be switched out the WiFi interface. 3) Run the WiMAX switching script. The ping packets will be switched out the WiMAX interface. ./SwitchingScripts/gec20_switch_to_wimax.sh 4) You’ve performed a handoff! Want proof? View the flows and packet counts on each OVS bridge before and after an interface-switch. 5) Alternate inferfaces and switch back to WiFi. ./SwitchingScripts/gec20_switch_to_wifi.sh Sponsored by the National Science Foundation GREESC2014 43 • Part I: Design/Setup – Use OpenFlow to perform L2 handoff • Part II: Execute – Configure and initialize software and scripts – Execute handoff experiment • Part III: Finish – Determine results – Kill processes – Shutdown node and logout Sponsored by the National Science Foundation GREESC2014 44 Teardown Experiment • When the experiment is done, on the Client node stop the Floodlight controller, stop OVS: ./StartupScripts/gec20_teardown.sh • On the Server node: ./StartupScripts/gec20_teardown.sh • Exit all SSH connections to nodes and power off resources: omf tell -a offh -t all • Exit Orbit console SSH connections. Sponsored by the National Science Foundation GREESC2014 45