Future Internet: New Network Architectures and Technologies

1. Future Internet: New Network Architectures and Technologies An Introduction to OpenFlow and Software-Defined Networking Christian Esteve Rothenberg esteve@cpqd.com.br

2. Agenda • Future Internet Research • Software-Defined Networking • An introduction to OpenFlow/SDN • The Role of Abstractions in Networking • Sample research projects • RouteFlow

3. Nick McKeown's SDN slides http://www.openflow.org/downloads/NickTalk_OFELIA_Feb2011.ppt GEC 10 OpenFlow Tutorial http://www.openflow.org/downloads/OpenFlowTutorial_GEC10.ppt Scott Shenker's talk on the “The Future of Networking, and the Past of Protocols” http://www.slideshare.net/martin_casado/sdn-abstractions The OpenFlow Consortium http://www.openflow.org Credits

4. What is OpenFlow?

5. Short Story: OpenFlow is an API Control how packets are forwarded (and manipulated) Implementable on COTS hardware Make deployed networks programmable not just configurable Vendor-independent Makes innovation easier Goal (experimenter’s perspective): Validate your experiments on deployed hardware with real traffic at full line speed Goal (industry perspective): Reduced equipment costs through commoditization and competition in the controller / application space Customization and in-house (or 3rd party) development of new networking features (e.g. protocols).

6. Why OpenFlow?

7. The Ossified Network Feature Million of linesof source code Billions of gates Routing, management, mobility management, access control, VPNs, … Feature 5400 RFCs Barrier to entry Operating System Specialized Packet Forwarding Hardware Bloated Power Hungry Many complex functions baked into the infrastructure • OSPF, BGP, multicast, differentiated services,Traffic Engineering, NAT, firewalls, MPLS, redundant layers, … • An industry with a “mainframe-mentality”, reluctant to change 8

8. Research Stagnation • Lots of deployed innovation in other areas • OS: filesystems, schedulers, virtualization • DS: DHTs, CDNs, MapReduce • Compilers: JITs, vectorization • Networks are largely the same as years ago • Ethernet, IP, WiFi • Rate of change of the network seems slower in comparison • Need better tools and abstractions to demonstrate and deploy

9. Closed Systems (Vendor Hardware) • Stuck with interfaces (CLI, SNMP, etc) • Hard to meaningfully collaborate • Vendors starting to open up, but not usefully • Need a fully open system – a Linux equivalent

10. Open Systems gap in the tool space none have all the desired attributes!

11. OpenFlow: a pragmatic compromise • + Speed, scale, fidelity of vendor hardware • + Flexibility and control of software and simulation • Vendors don’t need to expose implementation • Leverages hardware inside most switches today (ACL tables)

12. How does OpenFlow work? 14

13. Ethernet Switch

14. Control Path Control Path (Software) Data Path (Hardware)

15. OpenFlow Controller OpenFlow Protocol (SSL/TCP) Control Path OpenFlow Data Path (Hardware)

16. MAC src MAC dst IP Src IP Dst TCP sport TCP dport * * * 5.6.7.8 * * port 1 Action OpenFlow Example Controller PC OpenFlow Client Software Layer Flow Table Hardware Layer port 2 port 1 port 3 port 4 5.6.7.8 1.2.3.4

17. OpenFlow Basics Flow Table Entries Rule Action Stats Packet + byte counters • Forward packet to zero or more ports • Encapsulate and forward to controller • Send to normal processing pipeline • Modify Fields • Any extensions you add! Eth type Switch Port IP Src IP Dst IP ToS IP Prot L4 sport L4 dport VLAN pcp MAC src MAC dst VLAN ID + mask what fields to match

18. Switch Port Switch Port Switch Port MAC src MAC src MAC src MAC dst MAC dst MAC dst Eth type Eth type Eth type VLAN ID VLAN ID VLAN ID IP Src IP Src IP Src IP Dst IP Dst IP Dst IP Prot IP Prot IP Prot TCP sport TCP sport TCP sport TCP dport TCP dport TCP dport Action Action Action Examples Switching 00:1f:.. * * * * * * * * * port6 Flow Switching port3 00:20.. 00:1f.. 0800 vlan1 1.2.3.4 5.6.7.8 4 17264 80 port6 Firewall * * * * * * * * * 22 drop

19. 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 Action Examples Routing * * * * * * 5.6.7.8 * * * port6 VLAN Switching port6, port7, port9 vlan1 00:1f.. * * * * * * * *

20. OpenFlow Switch OpenFlow Switch OpenFlow Switch OpenFlow Switch OpenFlow Switch OpenFlow Switch Centralized vs Distributed ControlBoth models are possible with OpenFlow Centralized Control Distributed Control Controller Controller Controller Controller

21. Flow Routing vs. AggregationBoth models are possible with OpenFlow Flow-Based • Every flow is individually set up by controller • Exact-match flow entries • Flow table contains one entry per flow • Good for fine grain control, e.g. campus networks • Aggregated • One flow entry covers large groups of flows • Wildcard flow entries • Flow table contains one entry per category of flows • Good for large number of flows, e.g. backbone

22. Reactive vs. Proactive (pre-populated)Both models are possible with OpenFlow Reactive • First packet of flow triggers controller to insert flow entries • Efficient use of flow table • Every flow incurs small additional flow setup time • If control connection lost, switch has limited utility • Proactive • Controller pre-populates flow table in switch • Zero additional flow setup time • Loss of control connection does not disrupt traffic • Essentially requires aggregated (wildcard) rules

23. Usage examples Alice’s code: Simple learning switch Per Flow switching Network access control/firewall Static “VLANs” Her own new routing protocol: unicast, multicast, multipath Home network manager Packet processor (in controller) IPvAlice • VM migration • Server Load balancing • Mobility manager • Power management • Network monitoring and visualization • Network debugging • Network slicing … and much more you can create!

24. Intercontinental VM MigrationMoved a VM from Stanford to Japan without changing its IP. VM hosted a video game server with active network connections.

25. Quiz Time • How do I provide control connectivity? Is it really clean slate? • Why aren’t users complaining about time to setup flows over OpenFlow? (Hint: What is the predominant traffic today?) • Considering switch CPU is the major limit, how can one take down an OpenFlow network? • How to perform topology discovery over OpenFlow-enabled switches? • What happens when you have a non-OpenFlow switch in between? • What if there are two islands connected to same controller? • How scalable is OpenFlow? How does one scale deployments?

26. What can you not do with OpenFlow ver1.0 • Non-flow-based (per-packet) networking • ex. Per-packet next-hop selection (in wireless mesh) • yes, this is a fundamental limitation • BUT OpenFlow can provide the plumbing to connect these systems • Use all tables on switch chips • yes, a major limitation (cross-product issue) • BUT an upcoming OF version will expose these

27. What can you not do with OpenFlow ver1.0 • New forwarding primitives • BUT provides a nice way to integrate them through extensions • New packet formats/field definitions • BUT a generalized OpenFlow (2.0) is on the horizon • Optical Circuits • BUT efforts underway to apply OpenFlow model to circuits • Low-setup-time individual flows • BUT can push down flows proactively to avoid delays

28. Where it’s going • OF v1.1: Extensions for WAN • multiple tables: leverage additional tables • tags and tunnels • multipath forwarding • OF v2+ • generalized matching and actions: an “instruction set” for networking

29. OpenFlow Implementations(Switch and Controller) 31

30. OpenFlow building blocks Monitoring/debugging tools oftrace oflops openseer Stanford Provided ENVI (GUI) LAVI Expedient Applications n-Casting NOX Beacon SNAC Helios Maestro Controller Slicing Software FlowVisor Console FlowVisor Stanford Provided Commercial Switches Software Ref. Switch NetFPGA Broadcom Ref. Switch HP, NEC, Pronto, Juniper.. and many more OpenFlow Switches OpenVSwitch OpenWRT PCEngine WiFi AP 32

31. Current OpenFlow hardware Juniper MX-series NEC IP8800 UNIVERGE PF5240 WiMax (NEC) HP Procurve 5400 Netgear 7324 PC Engines Pronto 3240/3290 Ciena Coredirector More coming soon... Outdated! See ONF: https://www.opennetworking.org/ ONS: http://opennetsummit.org/ 33

32. Commercial Switch Vendors 34

33. Controller Vendors Outdated! See ONF: https://www.opennetworking.org/ ONS: http://opennetsummit.org/ 35

34. Growing Community Vendors and start-ups Providers and business-unit More... More... Note: Level of interest varies 36

35. Industry commitment Big players forming the Open Networking Foundation (ONF) to promote a new approach to networking called Software-Defined Networking (SDN). http://www.opennetworkingfoundation.org/

36. Software-Defined Networking (SDN) 38

37. Current Internet Closed to Innovations in the Infrastructure App App App Closed App App App Operating System Specialized Packet Forwarding Hardware Operating System App App App App App App Specialized Packet Forwarding Hardware Operating System Specialized Packet Forwarding Hardware Operating System Specialized Packet Forwarding Hardware App App App Operating System Specialized Packet Forwarding Hardware 39

38. “Software Defined Networking” approachto open it App App App Network Operating System App App App App App App Operating System Specialized Packet Forwarding Hardware Operating System App App App App App App Specialized Packet Forwarding Hardware Operating System Specialized Packet Forwarding Hardware Operating System Specialized Packet Forwarding Hardware App App App Operating System Specialized Packet Forwarding Hardware 40

39. The “Software-defined Network” 3. Well-defined open API 2. At least one good operating system Extensible, possibly open-source App App App 1. Open interface to hardware Network Operating System Simple Packet Forwarding Hardware Simple Packet Forwarding Hardware Simple Packet Forwarding Hardware Simple Packet Forwarding Hardware Simple Packet Forwarding Hardware 41

40. Virtualizing OpenFlow 42

41. Trend App App App App App App Controller 1 Controller 2 Controller 1 Controller 2 NOX (Network OS) Network OS Windows (OS) Linux Mac OS Windows (OS) Linux Mac OS Windows (OS) Linux Mac OS Virtualization or “Slicing” Virtualization layer OpenFlow x86 (Computer) Computer Industry Network Industry

42. Isolated “slices” Many operating systems, or Many versions App App App App App App App App Network Operating System 1 Network Operating System 2 Network Operating System 3 Network Operating System 4 Open interface to hardware Open interface to hardware Virtualization or “Slicing” Layer Simple Packet Forwarding Hardware Simple Packet Forwarding Hardware Simple Packet Forwarding Hardware Simple Packet Forwarding Hardware Simple Packet Forwarding Hardware

43. Flow Table Flow Table Controller Controller Switch Based VirtualizationExists for NEC, HP switches but not flexible enough Research VLAN 2 Research VLAN 1 Production VLANs Normal L2/L3 Processing

44. OpenFlow Switch OpenFlow Switch OpenFlow Switch OpenFlow FlowVisor & Policy Control FlowVisor-based Virtualization Heidi’s Controller Craig’s Controller Aaron’s Controller Topology discovery is per slice OpenFlow Protocol OpenFlow Protocol 46

45. OpenFlow Switch OpenFlow Switch OpenFlow Switch OpenFlow FlowVisor & Policy Control OpenFlow Protocol FlowVisor-based Virtualization http Load-balancer Multicast Broadcast Separation not only by VLANs, but any L1-L4 pattern dl_dst=FFFFFFFFFFFF tp_src=80, ortp_dst=80 OpenFlow Protocol

46. FlowSpace: Maps Packets to Slices

47. * * * * * * AaIP !AaIP * * * * * * * * * * * * Use Case: Aaron’s IP • A new layer 3 protocol • Replaces IP • Defined by a new Ether Type Switch Port MAC src MAC dst Eth type VLAN ID IP Src IP Dst IP Prot TCP sport TCP dport

48. Slicing traffic Untouched production traffic All network traffic Experiment #1 Research traffic Experiment #2 … Experiment N

49. Ways to use slicing Slice by feature Slice by user Home-grown protocols Download new feature Versioning