1. Incrementally Deployable Information Centric Networking 1 Seyed K. Fayazbakhsh, Yin Lin, Amin Tootoonchian, Ali Ghodsi, Teemu Koponen, Bruce Maggs, KC Ng, Vyas Sekar, Scott Shenker

2. Internet Service Model The network makes its best effort to deliver every datagram to the destination address specified in its header Example address: 128.2.205.42 “the narrow waist of IP” 2

3. ICN Service Model Given a request for named content, the network attempts to locate and retrieve the content Example request: retrieve DSAK832NSKAWKW282 Names may be bound to content cryptographically 3

4. Content Retrieval 4 Equip network with content caches ICN decouples “what” from “where” C S1 S2 Bind content names to intent Route based on content names e.g., find nearest replica C C e.g., CCN, DONA, NDN, 4WARD …. Today: 1) Ask search engine for name of server holding object 2) Resolve name to network address of server 3) Send request for object to server

5. This talk is not anti-ICN I am not an opponent of ICN 5

6. Benefits of deploying ICN 6 C C Lower latency Reduced congestion Support for mobility Intrinsic security e.g., CCN, DONA, NDN, 4WARD ….

7. 7 Difficulties deploying ICN C C Routers need to be replaced to support content-based routing and to incorporate caches e.g., CCN, DONA, NDN, 4WARD ….

8. 8 Motivation for this work Lower latency Reduced congestion Support for mobility Intrinsic security Can we get ICN gains without the pains? e.g., existing technologies? e.g., incrementally deployable? Benefits Difficulties Routers need to be replaced to support content-based routing and to incorporate caches

9. Approach: Attribute gains to tenets 9 Lower latency Reduced congestion Support for mobility Intrinsic security Decouple “what” from “where” Bind content names to intent Equip network with content caches Route based on content names Quantitative Qualitative

10. Key Takeaways To achieve quantitative benefits:  Just cache at the “edge”  With Zipf-like object popularities, pervasive caching and nearest-replica routing don’t add much To achieve qualitative benefits:  Build on HTTP 10 Basis for incrementally deployable ICN

11. Background and Approach Analyzing quantitative benefits Qualitative benefits  Incrementally deployable ICN Discussion 11 Outline

12. Design space of caching Quantitative benefits are largely due to caching Two key dimensions in this design space: – Cache placement E.g., everywhere? Edge? – Request routing E.g., shortest path, nearest replica? 12

13. Representative points in design space 13 ICN-SPEverywhereShortest path to origin ICN-NREverywhereNearest replica EdgeOnly at edge nodesShortest path to origin Edge-CoopOnly at edge nodesShortest path to origin Edge neighbors alone Cache Placement Request Routing

14. Object Popularities have Zipf Distribution 14 i th most popular item occurs with frequency proportional to 1/i α

15. Simulation setup 15 PoP-level topologies (Rocketfuel) augmented with access trees Real CDN request logs LRU replacement Assume name-based routing, lookup incurs zero cost Cache provisioning ~ 5% of objects per node Uniform or Proportional Edge

16. Request latency (hops) - Asia trace 16 Gap between all architectures is small (< 10%) Nearest-replica routing provides almost no benefit

17. Improvement in network congestion 17

18. Improvement in origin server load 18

19. Sensitivity Analysis 19 Baseline Even in best case, ICN-NR is only 17% better % gap ICN-NR - Edge Best caseNormalize Double Vary Zipf parameter, cache size, popularity skew, access tree degree

20. Edge cache deployment Incentives are aligned Users benefit if they deploy caches Incremental deployment is facilitated Benefits come immediately and don’t depend on router upgrades or other cache deployments 20

21. Background and motivation Approach Quantitative benefits of ICN Qualitative benefits  Incrementally deployable ICN Discussion 21 Outline

22. Design Rationale Parties that benefit should bear the costs – Consumers deploy ICN-aware proxies/caches – Content providers register names of objects ISPs leverage their existing investments in infrastructure 22

23. How Big is the CDN Market? 2012 Data (Source: Bloomberg BusinessWeek)

24. Revisiting Qualitative Aspects 2. Binding names to intents 24 1.Decouple names from locations Build on HTTP – Can be viewed as providing “get-by-name” abstraction – Can reuse existing web protocols (e.g., proxy discovery) Use self-certifying names e.g., “Magnet” URI schemes Extend HTTP for “crypto” and other metadata

25. Name Resolution System Reverse Proxy Origin Server Publish content Register L.P.idicn.org idICN: Content Registration L = content label P = Hash of public key 25 e.g., http://en.5671….fda627b.idicn.org/wiki/

26. Name Resolution System Proxy Edge Cache Reverse Proxy Automatic Proxy Discovery e.g., WPAD Origin Server idICN: Client Configuration Client 26

27. Name Resolution System Proxy Edge Cache Reverse Proxy 1. Rqst L.P.idicn.org Origin Server 2. Name resolution 6. Response 3. Rqst by address 5. Response + Metadata idICN: Content Delivery Client 4. Fetch Try it out: www.idicn.org 27

28. Conclusions Motivation: Gains of ICN with less pain – Latency, congestion, security – Without changes to routers or routing! End-to-end argument applied to ICN design space Can get most quantitative benefits with “edge” solutions – Pervasive caching, nearest-replica routing not needed Can get qualitative benefits with existing techniques – With existing HTTP + HTTP-based extensions – Incrementally deployable + backwards compatible idICN design: one possible feasible realization – Open issues: economics, other benefits, future workloads.. 28