How SDN will shape networking

Transcription

1 How SDN will shape networking Nick McKeown Stanford University With: Martín Casado, Teemu Koponen, Sco> Shenker and many others With thanks to: NSF, GPO, Stanford Clean Slate Program, Cisco, DoCoMo, DT, Ericsson, Google, HP, Huawei, NEC, Xilinx

2 Outline SDN: An industry change How SDN will shape networking 1. Empower network owners/operators 2. Increase the pace of innovaron 3. Diversify the supply chain 4. Build a robust foundaron

3 App App App App App App App App App App App Specialized Applications Specialized Operating System Specialized Hardware Windows (OS) Open Interface or Linux or Open Interface Microprocessor Mac OS Vertically integrated Closed, proprietary Slow innovation Small industry Horizontal Open interfaces Rapid innovation Huge industry

4 AppAppAppAppAppAppAppAppAppAppApp Specialized Features Specialized Control Plane Specialized Hardware Vertically integrated Closed, proprietary Slow innovation Open Interface Control Plane or Control Plane or Open Interface Merchant Switching Chips Horizontal Open interfaces Rapid innovation Control Plane

5 SoXware Defined Network (SDN) Control Program Global Network View Control Program 2. At least one Network OS probably many. Open- and closed- source Network OS 1. Open interface to packet forwarding

6 Simple example

7 OSPF RFC 2328: 245 pages Distributed System Builds consistent, up- to- date map of the network: 101 pages Dijkstra s Algorithm Operates on map: 4 pages

8 Example OSPF (Dijkstra) IS- IS New! OSPF Distributed System IS- IS Distributed System Distributed System Network OS OS Custom Hardware

9 OpenFlow AbstracRon Control Program A Control Program B Network OS If header = p, send to port 4 If header = q, overwrite header with r, add header s, and send to ports 5,6 If header =?, send to me Flow Table(s)

10 OpenFlow AbstracRon Match Header Match: 1000x01xx x <Match, Ac'on> Match on any header, or new header Allows any flow granularity Data Ac'on Forward to port(s), drop, send to controller Overwrite header with mask, push or pop Forward at specific bit- rate 10

11 OpenFlow AbstracRon Protocol Independent Construct Ethernet, IPv4, VLAN, MPLS, Construct new forwarding methods Backward CompaRble Run in exisrng networks Technology Independent Switches, routers, WiFi APs Cellular basestarons WDM/TDM circuits

12 SDN in development Domains Data centers Public clouds Enterprise/campus Cellular backhaul Enterprise WiFi WANs Home networks Products Switches, routers: About 15 vendors SoXware: 8-10 vendors and startups New startups. Lots of hiring in networking.

13 Outline SDN: An industry change How SDN will shape networking 1. Empower network owners/operators 2. Increase the pace of innovaron 3. Diversify the supply chain 4. Build a robust foundaron

14 How SDN will shape networking 1. Empower network owners and operators Example 1 Customize networks to local needs Eliminate unneeded features CreaRon of virtual, isolated networks 2. Increase the pace of innovaron InnovaRon at soxware speed Standards (if any) will follow soxware deployment Technology exchange with partners Technology transfer from universires

15 Example 1. Customizing the network Add distributed load- balancing Nikhil Handigol, Mario Flajslik, Srini Seetharaman

16 LOAD- BALANCER

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18 Experimental Setup Load- balancer Network OS: NOX

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21 Feature Feature Nikhil s Experiment: <500 lines of code Network OS: NOX

22 More videos openflow.org/videos

23 How SDN will shape networking 1. Empower network owners and operators Customize networks to local needs Eliminate unneeded features CreaRon of virtual, isolated networks 2. Increase the pace of innovaron InnovaRon at soxware speed Standards (if any) will follow soxware deployment Technology exchange with partners Technology transfer from universires Example 2

24 Example 2. InnovaRon at soxware speed Mininet: Rapid prototyping Brandon Heller, Bob Lantz, Nikhil Handigol, Vimal Jeyakumar

25 Mininet: Rapid Prototyping Load- balancer Network OS: NOX, Beacon, Processes with network namespace veth user kernel Network OS OpenFlow Open vswitch in kernel

26 Mininet: Rapid Prototyping Fast Emulate network with 10s of switches on one laptop Processes easily mapped to cores and servers Emulate network with 1000s of switches in server rack Rapid transfer Deploy unmodified code directly into live network Code available openflow.org/mininet

27 How SDN will shape networking 3. Diversify the supply chain A variety of soxware suppliers Vendors, homegrown, outsourced, open- source Common hardware abstracron, with extensions 4. Build a robust foundaron Standardized forwarding abstracron Provable network properres at every step Example 3

28 Example 3. Provable network properres Header Space Analysis Peyman Kazemian

29 Header Space Analysis: StaRc checking In today s networks, simple quesrons are hard Can A talk to B? What are all the packet headers from A that can reach B? Are there any loops in the network? Is VLAN X (or slice ) isolated totally from VLAN Y? Step 1: Model packet header as a point in {0,1} L Step 2: Model all switches as transforms of {0,1} L Step 3: Analyze reachability, loops, slice isolaron, Protocol independent, general, and surprisingly fast

30 Basic Model Header L Data Match 011XXX X1 L + Action Send to port 1, and Rewrite with: 100XX00..1X

31 Network Transfer FuncRon

32 ProperRes Network transfer funcron: set of Boolean expressions Only relies on <Match, AcRon> Subsumes Ethernet, IPv4, firewalls, NAT, Can prove reachability, isolaron and find loops Used to find faults in real networks e.g. Analyzed Stanford backbone in 10mins Code publicly available

33 Outline SDN: An industry change How SDN will shape networking 1. Empower network owners/operators 2. Increase the pace of innovaron 3. Diversify the supply chain 4. Build a robust foundaron

34 Thank you!

35 Experimental Setup with Slicing Experiment NOX Experiment Experiment NOX Experiment NOX Slicing Network Layer: OS: FlowVisor NOX

36 SoXware Defined Network (SDN) Control Programs Control Programs Control Programs Network VirtualizaRon Control Program A Abstract Network View Global Network View Network OS Control Program B

37 Example: New Data Center Cost 200,000 servers Fanout of 20 è 10,000 switches $5k vendor switch = $50M $1k commodity switch = $10M Control More flexible control Tailor network for services Quickly improve and innovate Savings in 10 data centers = $400M

38 Consequences for research Ease of trying new ideas ExisRng tools: NOX, Beacon, switches, Mininet More rapid technology transfer GENI, Ofelia and many more A stronger foundaron to build upon Provable properres of forwarding New languages and specificaron tools

39 Consequences for standards Standards will define the interfaces The role of standards will change: Network owners will define network behavior Features will be adopted without standards Programming world Good soxware is adopted, not standardized

40 Summary Networks becoming More programmarc Defined by owners and operators, not vendors Faster changing, to meet operator needs Lower opex, capex and power AbstracRons Will shield programmers from complexity Make behavior more provable Will take us places we can t yet imagine