The SAHARA Project: Composition and Cooperation in the New Internet

1. The SAHARA Project:Composition and Cooperationin the New Internet Randy H. Katz, Anthony Joseph, Ion Stoica Computer Science Division Electrical Engineering and Computer Science Department University of California, Berkeley Berkeley, CA 94720-1776

2. Presentation Outline • Service Architecture Opportunity • SAHARA Project Motivation • SAHARA Reference Architecture • Mechanisms for Service Composition • Summary and Conclusions

3. Presentation Outline • Service Architecture Opportunity • SAHARA Project Motivation • SAHARA Reference Architecture • Mechanisms for Service Composition • Summary and Conclusions

4. Traditional View of Networking • All about protocols and the OSI layers • Protocol details: link-state vs. distance vector, TCP • Protocol layering • Multiaccess technology • Switching and routing • Naming • Error control • Flow control & scheduling • Special topics like multicast and mobility

5. The New Opportunity • New things you can do inside the network • Connecting end-points to “services” with processing embedded in the network fabric • Not protocols but “agents,” executing in places in the network • Location-aware, data format aware • Controlled violation of layering necessary! • Distributed architecture aware of network topology • No single technical architecture likely to dominate: think overlays, system of systems

6. Distributed Service Architectures for Converged Networks • Converged Networks • Public Switched Telephone Network (PSTN) • Internet/Public Switched Data Network (PSDN) • Mobile Internet • Converged Structure? • Distributed Service Architecture • Services • “-Ility” connectivity • Rich call: new call “features” • Infrastructure services: proxies, search, commerce • Enablers for distributed apps: event & content distribution

7. Services in Converged Networks

8. Services in Converged Networks

9. New Kind of Communications-Oriented Service Architecture • Emerging, still developing, in a highly heterogeneous environment • Rapid development/deployment of new services & apps • Delivered to radically different end devices (phone, computer, info appliance) over diverse access networks (PSTN, LAN, Wireless, Cellular, DSL, Cable, Satellite) • Exploiting Internet-based technology core: clients/server, applications level routers, TCP/IP protocols, Web/XML formats • Beyond traditional “call processing” model: client-proxy-server plus application-level partitioning • Built upon a new business model being driven by the evolution of the Internet: traditional “managed” networks and services versus emerging “overlay” networks and services structured on top of and outside of the above • Composition via cooperation or brokering to achieve enhanced performance and reliability

10. Presentation Outline • Service Architecture Opportunity • SAHARA Project Motivation • SAHARA Reference Architecture • Mechanisms for Service Composition • Summary and Conclusions

11. JAL Restaurant Guide Service NTTDoCoMo UI Babblefish Translator Zagat Guide User Sprint Tokyo User Salt LakeCity Scenario: ServiceComposition

12. The “Sahara” Project • Service • Architecture for • Heterogeneous • Access, • Resources, and • Applications

13. Sahara Research Focus • New mechanisms, techniques for end-to-end services w/ desirable, predictable, enforceable properties spanning potentially distrusting service providers • Tech architecture for service composition & inter-operation across separate admin domains, supporting peering & brokering, and diverse business, value-exchange, access-control models • Functional elements • Service discovery • Service-level agreements • Service composition under constraints • Redirection to a service instance • Performance measurement infrastructure • Constraints based on performance, access control, accounting/billing/settlements • Service modeling and verification

14. Problems and Solutions“The Network Effect” • Creating and deploying new services • Development and deployment expense • Cost of 3G licenses and networks • “Even if I had $1 billion and set up 1000s of locations, I could never in my network have a completely ubiquitous footprint.”—Sky Dayton, founder of Boingo • Composition, cooperation, overlays • Achieving desirable end-to-end properties • Control of the end-to-end path • Cooperation, peering, overlays (brokering) • Evolving network services • Difficult to change global operational infrastructure • Overlays, cooperation

15. Cable Modem Premises- based AccessNetworks LAN Transit Net LAN LAN Private Peering Premises- based Core Networks Transit Net WLAN WLAN Internet Datacenter NAP Analog WLAN Transit Net Public Peering DSLAM Operator- based RAS Regional Wireline Regional Cell H.323 Data Cell Data H.323 Cell PSTN Voice Voice Internet Connectivity and Processing

16. Interconnected World:Agile or Fragile? • Baltimore Tunnel Fire, 18 July 2001 • “… The fire also damaged fiber optic cables, slowing Internet service across the country, …” • “… Keynote Systems … says the July 19 Internet slowdown was not caused by the spreading of Code Red. Rather, a train wreck in a Baltimore tunnel that knocked out a major UUNet cable caused it.” • “PSINet, Verizon, WorldCom and AboveNet were some of the bigger communications companies reporting service problems related to ‘peering,’ methods used by Internet service providers to hand traffic off to others in the Web's infrastructure. Traffic slowdowns were also seen in Seattle, Los Angeles and Atlanta, possibly resulting from re-routing around the affected backbones.” • “The fire severed two OC-192 links between Vienna, VA and New York, NY as well as an OC-48 link from, D.C. to Chicago. … Metromedia routed traffic around the fiber break, relying heavily on switching centers in Chicago, Dallas, and D.C.”

17. Applications (Portals, E-Commerce, E-Tainment, Media) Appl Infrastructure Services (Distribution, Caching, Searching, Hosting) AIP ISV Application-specific Servers (Streaming Media, Transformation) ASP Internet Data Centers Application-specific Overlay Networks (Multicast Tunnels, Mgmt Svrcs) ISP CLEC Internetworking (Connectivity) Global Packet Network Internet Service Composition

18. Peering Point Peering Point Competition vs. Cooperation • Internet Service Providers: Competition • Peering for packet transport: BGP protocol • Charging based on traffic volumes ISP A Hot Potato Routing ISP B

19. Composition and Cooperation:Mobile Virtual Network Operator MVNO has everything but its own physical network

20. InterCall one2one Competition one2one 1-to-1 Relationship M-to-N Relationships Mobile Virtual Network Operator:Composition and Cooperation

21. Operator A GGSN GPRS Peering Network Operator C BG BG DNS DNS DNS DNS DNS R R DNS GRX GPRS Peering Network R DNS .gprs R R R SGSN GRX GRX R R R R R GRX Operator C Operator B BG DNS BG R R DNS SGSN SGSN GPRS Transit: Peering, Cooperation, Composition Per Johannson, Ericsson Research

22. New Primary Transit PeeringPolicy-Based Routing • Multi-homing • Reliability of network connectivity • Traffic discrimination Primary Transit Network End Network Berkeley Campus Dorm Traffic Alternative Transit Network Research Traffic Fail-over Peer Network Peer Network Peer Network Peer Networks CalREN

23. Administrative domain Administrative domain Admin domain Admin domain Admin domain OverlaysCreating New Interdomain Services • Deploy new services above the routing layer • E.g., interdomain multicast management and peering • E.g., alternative connectivity for performance, resilience Isolated Intra-cloud service Traditional unicast peering Steve McCanne

24. OverlaysBrokered Resources for Applications • Examples: • Multicast management and peering at application level • Implement performance qualities at overlay level Steve McCanne

25. Composition:Wireless ISPs (wISPs) • T-Mobile Wireless Broadband (MobileStar), WayPort • Traditional network ISP, subscription-based services in public places • Hotels (Wayport), airports (Wayport @ SJ airport), airport clubs (T-Mobile @ AA Admirals Club), and cafes (T-Mobile @ Starbucks) • Diverse billing models: e.g., 24-hour subscription at a hotel • Boingo, Joltage, hereUare, NetNearU • “Aggregator” of access, e.g., Boingo aggregates Wayport, hereUare • Client s/w including network sniffer/location finder, back-end authentication/secure VPN/settlement services • Revenue sharing with micro ISPs/single local network (SLN) • Diverse billing models: subscriptions as well as pay per use • Sputnik • Cooperative wireless neighbor-to-neighbor networks • Ipass, GRIC • Secure remote access for mobile employees • Simplify connection establishment and login, wireless VPN support

26. VPN Operator, Client-Software Private Brand Net Operator (MVNO) WISP Aggregator Single Sign-on Unified Billing SLN Aggregator Revenue Sharing Full Service Network Operator Full Service Network Operator Single Location Network Operator (SLN) Single Location Network Operator (SLN) Single Location Network Operator (SLN) Cooperative Networking Composition of Wireless Infrastructure Services Billing, ECommerce Authentication Inter-site Mobility Full Service Network Operator Premises-based Access

27. Presentation Outline • Service Architecture Opportunity • SAHARA Project Motivation • SAHARA Reference Architecture • Mechanisms for Service Composition • Summary and Conclusions

28. Technical Challenges • Trust management and behavior verification • Meet promised functionality, performance, availability • Adapting to network dynamics • Actively respond to shifting server-side workloads and network congestion, based on pervasive monitoring & measurement • Awareness of network topology to drive service selection • Adapting to user dynamics • Resource allocation responsive to client-side workload variations • Resource provisioning and management • Service allocation and service placement • Interoperability across multiple service providers • Interworking across similar services deployed by different providers

29. Service Composition Models • Cooperative • Individual component service providers interact in distributed fashion, with distributed responsibility, to provide an end-to-end composed service • Brokered • Single provider, the Broker, uses functionalities provided by underlying service providers, encapsulates these to compose an end-to-end service • Examples • Cooperative: roaming among separate mobile networks • Brokered: JAL restaurant guide

30. Cooperative Negotiation & control path Service Service Service Data flow Brokered Negotiation & control path Broker Service Service Service Data flow Service Composition Models

31. Service Composition Layered Reference Model for Service Composition End-User Applications Applications Services Application Plane Middleware Services End-to-End Network With Desirable Properties Enhanced Paths Connectivity Plane Enhanced Links IP Network

32. Measurement-based Adaptation Interoperabilty Policy Management Dynamic Resource Allocation Trust Management/ Verification Underlying Composition Techniques Services at Layer i-1 Services at Layer i-1 Services at Layer i-1 Services at Layer i-1 Other Services at Layer i Component Services Layered Reference Modelfor Service Composition Composed Service at Layer i

33. Layered Reference Modelfor Service Composition • Connectivity Plane • End-to-end network with desirable properties composed on top of commodity IP network • Enhanced Links & Paths: QoS and protocol verification within and between connectivity service providers • Applications Plane • Services strategically placed and actively managed within the network topology • Applications and Middleware Services: end-client oriented vs. infrastructure oriented

34. Presentation Outline • Service Architecture Opportunity • SAHARA Project Motivation • SAHARA Reference Architecture • Mechanisms for Service Composition • Summary and Conclusions

35. Mechanisms for Service Composition • Measurement-based Adaptation • Examples • General-purpose third party end-to-end Internet host distance monitoring and estimation service • Universal In-box: Application-specific middleware measurement layer to exchange network and server load using link-state algorithm • Content Distribution Networks: measurement-based DNS-based server selection to redirect client to closest service instance

36. Mechanisms for Service Composition • Utility-based Resource Allocation Mechanisms • Examples • Auctions to dynamically allocate resources; applied for spectrum/bandwidth resource assignments to MVNO from underlying competiting MNOs • Congestion pricing: influence user behavior to better utilize scarce resources; applied in: • Voice port allocation to user-initiated calls in H.323 gateway/Voice over IP service management • Wireless LAN bandwidth allocation and management • H.323 gateway selection, redirection, and load balancing for Voice over IP services

37. Mechanisms for Service Composition • Trust Mgmt/Verification of Service & Usage • Authentication, Authorization, Accounting Services • Authorization control scheme w/ credential transformations to enable cross-domain service invocation • Federated admin domains with credential transformation rules based on established peering agreements • AAA server makes authorization decisions, liberating providers from preparing rules for each affiliated domain • Service Level Agreement Verification • Verification and usage monitoring to ensure properties specified in SLA are being honored • Border routers monitoring control traffic from different providers to detect malicious route advertisements

38. Mechanisms for Service Composition • Policy Management • Visibility into local policies to better coordinate global policies among (cooperating) service providers • Developing inter-AS architecture for load balancing, performance and failure mode policies to be applied throughout the network • Internet topology discovery through AS relationship map of the Internet plus measurement infrastructure • Policy agent framework for inter-AS negotiation to manage incoming traffic

39. Mechanisms for Service Composition • Interoperability through Transformation • Interoperability of data, protocols, policies among composed service providers • Example • Broadcast federation: global multicast service composed from multicast implementations in different provider domains • Protocol transformation gateways between admin domains employing non-interoperable multicast protocol implementations

40. Presentation Outline • Service Architecture Opportunity • SAHARA Project Motivation • SAHARA Reference Architecture • Mechanisms for Service Composition • Summary and Conclusions

41. Summary and Conclusions • Goal: Evolve (mobile) Internet architecture to better support multi-network/multi-service provider model • Dynamic environment, location-based implies larger numbers of service providers & service instances • Status: architectural specification driven by selected applications and underlying wide-area services • Focus: • Composition across confederated vs. independent service providers: peer-to-peer vs. brokering • Explore new techniques/technologies: • Market-based mechanisms • Trust management, SLA verification, perf. monitoring

42. Recent Publications • C. Chuah, L. Subramanian, A. D. Joseph, R. H. Katz, “QoS Provisioning Using A Clearing House Architecture,” 8th International Workshop on Quality of Service (IWQOS 2000), Pittsburgh, PA, (June 2000). • S. Zhuang, B. Zhao, A. Joseph, R. H. Katz, J. Kubiatowicz, “Bayeux: An Architecture for Wide-Area, Fault-Tolerant Data Dissemination Protocol,” ACM NOSSDAV 2001, New York, (June 2001). • Z. Mao, W. So, R. H. Katz, “Network Support for Mobile Multimedia Using a Self-Adaptive Distributed Proxy,” ACM NOSSDAV 2001, New York, (June 2001). • Y. Chen, A. Bargteil, R. H. Katz, “Quantifying Network Denial of Service: A Location Service Case Study,” Third International Conference on Information and Communication Security (ICICS’2001), Xi’an, China, (November 2001).

43. Recent Publications • J. Shih, R. H. Katz, “Pricing Experiments for a Computer-Telephony-Service Usage Allocation,” IEEE Globecom 2001, San Antonio, TX, (November 2001). • Y. Chen, R. H. Katz, J. Kubiatowicz, “Replica Placement for Scalable Content Delivery,” Proceedings First International Conference on Peer-to-Peer Systems (IPTPS’02), Cambridge, MA, (March 2002). • T. Suzuki, R. H. Katz, “An Authorization Control Framework to Enable Service Composition Across Domains,” Proceedings Eleventh World Wide Web Conference (WWW2002), Honolulu, HI, (May 2002). • M. Caesar, D. Ghosal, R. H. Katz, “Resource Management for IP Telephony Networks,” Proceedings 10th International Workshop on Quality of Service (IWQoS), Miami Beach, FL, (May 2002). • S. Machiraju, M. Seshadri, I. Stoica, “A Scalable and Robust Solution for Bandwidth Allocation,” Proceedings 10th International Workshop on Quality of Service (IWQoS), Miami Beach, FL, (May 2002).

44. Recent Publications • Y. Chawathe, M. Seshadri, “Broadcast Federation: An Application-layer Broadcast Internet,” Proceedings Network and Operating System Support for Digital Audio and Video (NOSSDAV’02), Miami Beach, FL, (May 2002). • L. Subramanian, V. Padmanabhan, R. H. Katz, “Geographic Properties of Internet Routing,” USENIX Conference, Monterey, California, (June 2002). • Z, Mao, C. Cranor, F. Douglis, M. Rabinovich, O. Spatscheck, J. Wang, “A Precise and Efficient Evaluation of the Proximity between Web Clients and their Local DNS Servers,” USENIX Conference, Monterey, California, (June 2002). • L. Subramanian, S. Agarwal, J. Rexford, R. H. Katz, “Characterizing the Internet Hierarchy from Multiple Vantage Points,” IEEE Infocomm Conference, New York, NY, (June 2002).

45. Recent Publications • J. Shih, R. H. Katz, “Evaluating Tradeoffs of Congestion Pricing for Voice Calls,” Extended Abstract, ACM Sigmetrics Conference, San Diego, California, (July 2002). • J. Shih, R. H. Katz, “Evaluating the Tradeoffs of Congestion Pricing for Voice Calls,” 2002 International Symposium on Performance Evaluation of Computer and Telecommunication Systems (SPECTS 2002), San Diego, California, (July 2002). • B. Raman, R. H. Katz, “Emulation-based Evaluation of an Architecture for Wide-Area Service Composition,” 2002 International Symposium on Performance Evaluation of Computer and Telecommunication Systems (SPECTS 2002), San Diego, California, (July 2002). • Z. Mao, R. Govindan, S. Shenker, R. H. Katz, “Route Flap Damping Exacerbates Internet Routing Convergence.” ACM SIGCOMM Conference, Pittsburgh, PA, (August 2002).

46. Recent Publications • B. Raman, S. Agrawal, Y. Chan, M. Caesar, W. Cui, P. Johannson, K. Lai, T. Lavian, S, Machiraju, Z. Mao, G. Porter, T. Roscoe, M. Seshadri, J. Shih, K. Sklower, L. Subramanian, T. Suzuki, S. Zhuang, A. D. Joseph, R. H. Katz, I. Stoica, “The SAHARA Model for Service Composition across Multiple Providers,” Pervasive Computing 2002, Zurich, Switzerland, (August 2002). • Z. Mao, R. H. Katz, “A Framework for Universal Service Access using Device Ensembles,” CRA Grace Murray Hopper Celebration of Women in Computer Science Conference, Vancouver, BC, (October 2002).

47. SAHARA: A Revolutionary Service Architecture for Future Telecommunications Systems Randy H. Katz, Anthony Joseph, Ion Stoica Computer Science Division Electrical Engineering and Computer Science Department University of California, Berkeley Berkeley, CA 94720-1776

48. Work in Progress • Enhanced Links • Enhanced Paths • Middleware Services • Applications Services

49. Work in Progress • Enhanced Links • Congestion Pricing for Access Links • Auction-based Resource (Bandwidth) Allocation • Traffic Policing/Verification of Bandwidth Allocation

50. Computer Access Router Local Area Network Internet QoS Computer $ Congestion Pricing at Access Links • Setup • 10 users • 3 QoS (Slow-going, Moderate, & Responsive)differ on degree of traffic smoothing • 24 tokens/day, 15 minutes of usage per charge • Acceptable • Users make purchasing decision at most once every 15 minutes • Feasible • Changing prices cause users to select different QoS • Effective • If entice half of users to choose lower QoS during congestion, then reduce burstiness at access links by 25%