1. 1 CS294-3: Distributed Service Architectures in Converged Networks Randy H. Katz Computer Science Division Electrical Engineering and Computer Science Department University of California Berkeley, CA 94720-1776

2. 2 Outline What is this Course About? Technology Trends Evolution of the Internet Business Trends Implications and Issues Summary and Conclusions

3. 3 Outline What is this Course About? Technology Trends Evolution of the Internet Business Trends Implications and Issues Summary and Conclusions

4. 4 Traditional “Networking” Course All about protocols and the OSI seven 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. 5 What is New? 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. 6 Definition of Terms Converged Networks –Public Switched Telephone Network (PSTN) –Internet/Public Switched Data Network (PSDN) –Mobile Internet –Converged Structure? Distributed Service Architecture –Services »“-Ility” connectivity »New call “features” »Infrastructure services »Enables distributed applications

7. 7 What is this Course About? Emerging, yet still developing, view of a new kind of communications-oriented service architecture 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

8. 8 Course Structure Seminar! We learn from each other! –Avoid traditional lecture-oriented course –More student-led presentations, discussions –Project will be the group design and evaluation of a distributed service architecture –2 Units/2 Hours per week –Every student will develop materials and lead one hour discussion on a selected area of technology; to be written up by mid-semester as a “term paper” –Project: depending on class size, we will have collaborating and competing teams develop a design and evaluation for future converged network service architecture –20% Term Paper –30% Class Discussion/Presentation –50% Class Project

9. 9 Relevant Technologies (Partial List!) PSTN architecture: AIN, SS-7 SLAs 3GPP/GPRS/Edge Voice over IP with SIP Internet Multimedia Architecture (RTSP, SIP, SAP, RTP/RTCP, IPv6, IP Mobility, DiffServ, Multicast) SyncML Parlay, JTAPI WAP Symbian/Embedded OS Sun ONE,.Net, Corba, TINA SMS/MMS + Other Messaging Platforms MGCP SIP Instant Messaging + Presence Leveraging Mobile Location Services WAP Radius/Diameter/Single Sign On BGP MPLS Core vs. Access Networking Technologies Mobey Formum Operator Wireless LAN DRM, PKI SCPTP/IETF Sigtran Architecture of Internet Data Centers and NAPs

10. 10 Nokia’s Mobile World View Network Environment Identity/ Addressing Interaction Internet Intranet 2G/3G Messaging Browsing Rich Call URL Email Phone #

11. 11 Nokia’s Mobile Service Matrix Content Information Entertainment News Banking & Finance Buy & Sell Travel Music TV Lifestyle Fun Games Astrology Dating Comms Messaging E-Mail FAX Rich Call Productivity Organizers Personal Assistants Tools Misc Business Intranet & Extranet Access Info Mgmt Enterprise Comms VPNs Telematics

12. 12 Nokia’s Mobile Internet “Business Architecture” Service Providers End Users Developers Content Providers Consumption User Interface Applications Rich Call Browsing Msg Middleware OS Network Hardware Connection Application Gateways Rich Call Browsing Msg Middleware OS Network Hardware Consumption Applications Rich Call Browsing Msg Middleware OS Network Hardware

13. 13 Application Programming Interface Application Layer Other and 3 rd Party Applications Browser App Email App Phone App Streaming App Instant Messaging Application Browser Support Msg Support Rich Call Support Application Development Interfaces Mobile Internet Layer App Framework and UI Support SDK Interfaces Network Interface SDK Libraries Network Protocols App Protocols Platform Applications Interfaces Platform Layer I/O Drivers I/O Hardware OS Core Processors & Memory Link Layer Drivers Network Hardware

14. 14 Statistics Perf Monitoring Sys Monitoring Billing Data Collection Operator Care Self-Care Provisioning Operational Support Nokia’s mPlatform Architecture Firewall Network Connectivity Process Handling Subscriber Access Control Load Balancing WAP & PDA Proxy Subscriber Authentication Service Access Control Access Functions Audit Manager (Billing) Operator Manager Presentation Manager Security Manager Notification Manager Navigation Manager Scenario Manager Personalization Manager Session Manager Common Enabling Application Functions Application Interface

15. 15 BS One Operator’s Viewpoint Radio Access Network Core Network Transport BS Spectrum QoS Cap Local Radio Access Capacity On-Demand Service Domain Data Center Data Storage Processing Cap Support Systems Services HLR Charging Apps 3 rd Party Apps Content Marketing & Sales Pricing Structure Distribution Packaging Customer Service Billing

16. 16 PSTN GSM Pager Access Network Plane ICEBERG Network Plane ISP Plane A B IAP ISP1ISP2ISP3 IAP NY iPOP SF iPOP Clearing House ICEBERG Architecture IAP PR CA PAC APC NMS Name Mapping Service: Maps ICEBERG unique ID  service end point Preference Registry / Personal Activity Coordinator: user profile / user tracking Automatic Path Creation service: creates transcoding datapath between endpoints SF iPOP iPOP: Clustered computing environ. Call Agent: handles signaling, one per device per call party

17. 17 Edge/Access Networks “Core” Wide-Area Network Performance Measurement and Monitoring Wide-Area Services: Discovery, Mobility, Trust, Availability Adaptation Services: Introspection, Tacit Information Extraction/Organization Context-Awareness Services: Activity Tracking/Coordination, Preferences Specification/Interpretation Prototype Applications: Universal In-Box, Context-Aware UI, Group Collaboration Possible High Level “Layered” View of Service Architecture

18. 18 Outline What is this Course About? Technology Trends Evolution of the Internet Business Trends Implications and Issues Summary and Conclusions

19. 19 Technology Trends Computing –Convergence, Divergence, Scale Networks –Internet vs. Telephone Network –Wireless/Mobile Access Services –E-commerce, M-commerce/M-transactions (iMode), Content –Messaging as a major application (P2P, P2M, M2M) Architecture –Integrated (“Closed”) vs. Composed (“Open”) Content, Distribution, Access Architecture –Managed vs. Overlay Networks and Services –Competitive vs. Cooperative Service Providers

20. 20 Internet Growth Million Servers Annual Growth Rate > 50% Million U.S. Surfers Annual Growth Rate > 20% The Industry Standard, 2 July 2001

21. 21 Convergence? Eniac, 1947 Telephone, 1876 Computer + Modem 1957 Early Wireless Phones, 1978 First Color TV Broadcast, 1953 HBO Launched, 1972 Interactive TV, 1990 Handheld Portable Phones, 1990 First PC Altair, 1974 IBM PC, 1981 Apple Mac, 1984 Apple Powerbook, 1990 IBM Thinkpad, 1992 HP Palmtop, 1991 Apple Newton, 1993 Pentium PC, 1993 Red Herring, 10/99

22. 22 Game Consoles Personal Digital Assistants Digital VCRs (TiVo, ReplayTV) Communicators Smart Telephones E-Toys (Furby, Aibo) Divergence! Pentium PC, 1993 Atari Home Pong, 1972 Apple iMac, 1998 Pentium II PC, 1997 Palm VII PDA, 1999 Network Computer, 1996 Free PC, 1999 Sega Dreamcast, 1999 Internet-enabled Smart Phones, 1999 Red Herring, 10/99 Proliferation of diverse end devices and access networks

23. 23 Automobiles 663 Million Telephones 1.5 Billion Electronic Chips 30 Billion X-Internet “X-Internet” Beyond the PC Forrester Research, May 2001 93 Million 407 Million Internet Computers Internet Users Today’s Internet

24. 24 “X-Internet” Beyond the PC Forrester Research, May 2001 Millions Year X Internet PC Internet

25. 25 The Shape of Things Now Siemens SL45 –A cellular phone with voice command, voice dialing, intelligent text for short messages –An MP3 player & headset –A digital voice recorder –Supports “Mobile Internet” with a built-in WAP Browser –Can store »45 minutes of music »5 hours of voice notes »“Unlimited” addresses/phone numbers

26. 26 The Shape of Things Now Kyocera QCP 6035 –Palm OS/CDMA –Palm PIM Applications –Supports “Mobile Internet” with a built-in WAP Browser –8 MBytes

27. 27 The Shape of Things to Come Toyota Pod Concept Car –Co-designed with Sony –Detects driver’s skill level and adjust suspension –Detects driver’s mood (pulse rate, perspiration), compensates for road rage and incorporates a mood meter (happy vs. angry face) –Inter-pod wireless LAN to communicate intentions between vehicles, such as passing –Individual entertainment stations for each passenger

28. 28 The iMode Story: It is About Services 27M Internet-capable cell phone sub- scribers (10/01); 50K iMode Web Sites World’s largest ISP, first to deploy 3G “Freedom of Multimedia Access” (FOMA) Not just about Japanese teenagers Applications UsedUser Ages Economist Magazine, 13 Oct 2001

29. 29 After the PC … True “Convergence” Not just about gadgets or access technologies About services and applications, and how the network can best support them Increasing, not decreasing, diversity Bottlenecks moving from core towards edge Enabled by computing embedded in communications fabric: wide-area, topology- aware, distributed computing

30. 30 Where is the next “narrow waist”? What is the Internet? “It’s the TCP/IP Protocol Stack” Applications –Web –Email –Video/Audio TCP/IP Access Technologies –Ethernet (LAN) –Wireless (LMDS, WLAN, Cellular) –Cable –ADSL –Satellite TCP/IP Applications Access Technologies “Narrow Waist” Transport Services and Representation Standards Open Data Network Bearer Service Middleware Services Network Technology Substrate

31. 31 Telephony Evolution Mobility/Wireless driving end-to-end digitization of the telephony system –Shift towards IP-based infrastructure (Nokia “All-IP” Architecture) Converged Services –AT&T »Cell Phone, Telephone, ISP, Video on Demand (Cable) »Universal Billing Systems –Sprint: $0.05/min local/long distance, wired/wireless Computer-Telephony Integration –Call Centers, Software-based PBXs, PSTN By-Pass –Consumer-to-Business E-commerce (e.g., Lands End) –Speech-Enabled Services (e.g., “Concierge”)

32. 32 Internet vs. Telephone Net Strengths –Intelligence at ends –Decentralized control –Operates over heterogeneous access technologies Weaknesses –No differential service –Variable performance delay –New functions difficult to add since end nodes must be upgraded –No trusted infrastructure Strengths –No end-point intelligence –Heterogeneous devices –Excellent voice performance Weaknesses –Achieves performance by overallocating resources –Difficult to add new services to “Intelligent Network” due to complex call model –Expensive approach for reliability

33. 33 Data Applications Source: CTIA Web Page Peter D. Hart Research Associates, March 1997 After basic wireless telephony service Cellular Services Most Often Requested Call Forwarding37% Paging33% Internet/E-Mail24% Traffic/Weather15% Conference Calling13% News3%

34. 34 Services and Applications: E-Commerce Consumer Services –Consumer-driven QoS: improved Web access “experience” –Converged digital video + web content (e.g., HVML) –Unified billing: pay-per-view movie plus ad-induced pizza purchase –Content delivery: file mover/software upgrades/digital audio/video –Infrastructure storage: back-up, photos, mp3s, videos, TV tapings Consumer-to-Business Services –Web-based + (IP-based) Telephone –New kinds of integrated call centers: e.g., Lands End M-Commerce –Location-sensitive ad insertion –Unified billing for telecom access + purchases

35. 35 Outline What is this Course About? Technology Trends Evolution of the Internet Business Trends Implications and Issues Summary and Conclusions

36. 36 The ARPANet Paul Baran –RAND Corp, early 1960s –Communications networks that would survive a major enemy attack ARPANet: Research vehicle for “Resource Sharing Computer Networks” –2 September 1969: UCLA first node on the ARPANet –December 1969: 4 nodes connected by phone lines SRI 940 UCLA Sigma 7 UCSB IBM 360 Utah PDP 10 IMPs BBN team that implemented the interface message processor

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38. 38 ARPANet Evolves into Internet Web Hosting Multiple ISPs Internet2 Backbone Internet Exchanges Application Hosting ASP: Application Service Provider AIP: Application Infrastructure Provider (e-commerce tookit, etc.) ARPANet SATNet PRNet TCP/IPNSFNetDeregulation & Commercialization 19651975198519952005 WWW ISP ASP AIP

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41. 41 Parallel Backbones Qwest IP Backbone (Late 1999) Digex Backbone GTE Internetworking Backbone

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43. 43 Network “Cloud”

44. 44 Regional Net Regional Nets + Backbone Regional Net Regional Net Regional Net Regional Net Regional Net Backbone LAN

45. 45 ISP Backbones + NAPs + ISPs ISP Business ISP Consumer ISP LAN NAP Backbones Dial-up

46. 46 Core Networks Covad Core Networks + Access Networks @home ISP Cingular Sprint AOL LAN NAP Dial-up DSL Always on NAP Cable Head Ends Cell Satellite Fixed Wireless

47. 47 Covad Computers Inside the Core @home ISP Cingular Sprint AOL LAN NAP Dial-up DSL Always on NAP Cable Head Ends Cell Satellite Fixed Wireless

48. 48 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.”

49. 49 Service-Level Peering Need common architecture for different vendors to create components and work with one another while still competing Some Observations –IP originally designed for cooperative administrative environments –BGP “recently” retrofitted to architecture to manage administrative relationships –How to design in managed peering from first principles? Solution Based on Redirection Above IP –Define the redirection architecture –New client/infrastructure protocol & API (a la DNS) –Do so in backward compatible way

50. 50 Isolated multicast clouds Traditional unicast peering multicast cloud multicast cloud multicast cloud multicast cloud multicast cloud Application-Specific Overlays E.g., solve the multicast management and peering problems by moving up the protocol stack Steve McCanne

51. 51 Application-Level Servers/Routers Solve the multicast management and peering problems by moving up the protocol stack Steve McCanne

52. 52 Outline What is this Course About? Technology Trends Evolution of the Internet Business Trends Implications and Issues Summary and Conclusions

53. 53 Global Packet Network Internetworking (Connectivity) ISP CLEC Layerized Internet Service Business Model Application-specific Overlay Networks (Multicast Tunnels, Mgmt Svrcs) Applications (Portals, E-Commerce, E-Tainment, Media) Application-specific Servers (Streaming Media, Transformation) ASP Internet Data Centers Appl Infrastructure Services (Distribution, Caching, Searching, Hosting) AIP ISV

54. 54 Application Services Web Site Caching Comparison Shopping Interactive TV Guide Local Ad Insertion Streaming Media A New Kind of Internet Infrastructure Services Terminal Equipment & Access Network PC, Set-top Box. Smart Phone, Game Console, E-toys Server Computing Web Hosting Server “Platform” ISP Caching Search Engine Applications Web, E-mail, Chat, E-commerce, E-tainment Regional Communications ISP Wide-Area Communications High Performance Backbone Customer

55. 55 Content Open vs. Closed Access to Services AT&T Cable @Home Excite Cable, DSL, MMDS, LMDS, Satellite ISP Backbone Provider Portal Web Sites Routing & Distribution Local Network Management Access Time/Warner Roadrunner AOL Dial-up AOL AOL/Netscape Time/Warner Covad DSL CNCX Williams Web Closed end-to-end pipe: optimized performance But companies developing compelling infrastructure technology that any content provider or ISP can adopt Closed system can’t benefit from these

56. 56 Server and site availability Balanced server and site load Rapid change Network and application flexibility Scalability Complex site administration From Network Management to Service Management Server Load Balancing Rapid problem diagnosis/ isolation Service level measurement Multi-tier resource monitoring Preferential Services Resource Provisioning Self-tuning Problem prevention Chris Morino, Resonate

57. 57 Network Failure 18.2% ISP connection down LAN segment overloaded Service Reliability is Critical Systems Server Failure 20% OS Failure 24.6% CPU overloaded NIC failure Administration 8.7% Applications Failure 28.5% Process hung Slowed database performance Source: IDC Chris Morino, Resonate

58. 58 Competition vs. Cooperation Internet Service Providers: Competition –Peering for packet transport: BGP protocol –Charging based on traffic volumes ISP A ISP B Hot Potato Routing Peering Point Peering Point

59. 59 Mobile Internet Might Be Different Than Wired Internet Wireless is a smarter pipe –Location-awareness –UI dictates need for personalization, mediation Clear billing authority: it’s the access provider –People actually do pay for transport –Reverse billing allows content provider to charge for service Peering as a necessity –Operators provide local service –Roaming agreements provide basis for service peering –Well understood arrangements for settlements –New economies driving towards shared network deployment Person-to-Person communications is a killer app Microsoft’s non-monopoly

60. 60 Cooperation and Peering 3G Spectrum Auctions: 150 billion ECU; Capital outlays may match spectrum expenses, all before first revenue New business models in Mobile Networks –Compelling services make the difference –Collaborate on deployment of physical network –Compete on provisioning of services Peering For More Than Connectivity –Horizontal architecture of services on top of networks –Virtual Home Environments –Relationships between operators, billing agents, service providers

61. 61 Any Way to Build a Network? Partitioning of frequencies independent of actual subscriber density –Successful operator oversubscribe resources, while less popular providers retain excess capacity –Different flavor of roaming: among collocated/competing service providing Duplicate antenna sites –Serious problem given community resistance Redundant backhaul networks –Limited economies of scale

62. 62 The Case for Horizontal Architectures “The new rules for success will be to provide one part of the puzzle and to cooperate with other suppliers to create the complete solutions that customers require.... [V]ertical integration breaks down when innovation speeds up. The big telecoms firms that will win back investor confidence soonest will be those with the courage to rip apart their monolithic structure along functional layers, to swap size for speed and to embrace rather than fear disruptive technologies.” The Economist Magazine, 16 December 2000

63. 63 Feasible Alternative: Horizontal Competition vs. Vertical Integration Service Operators “own” the customer, provide “brand”, issue/collect the bills Independent Backhaul Operators Independent Antenna Site Operators Independent Owners of the Spectrum Microscale auctions/leases of network resources Emerging concept of Virtual Operators

64. 64 Internet (Multiservice Provider today) PSTN Network (Multiservice Provider today) Backhaul Network Access Network Backhaul Network Access Network Business as Usual: Vertical Integration Each operator owns own frequencies, cell sites, backhaul network PBMS Sprint

65. 65 Access Network Business Unusual: Horizontal Competition Internet PSTN Network Backhaul Network Access Network Backhaul Network Sprint “leases” frequencies from PBMS, on-demand, based on the density of its subscribers “Mom&Pop” Cell Site Operators

66. 66 Virtual Operator MVNO: Virgin Mobile and One2One in UK –Distinguish based on marketing and billing plan innovations –VM competes for subscribers but uses One2One’s network “Operators without subscribers”: local premises deploy own access infrastructure –Better coverage/more rapid build out of network –Deployments in airports, hotels, conference centers, office buildings, campuses, … Overlay service provider (e.g., PBMS) vs. organizational service provider (e.g., UCB IS&T) –Single bill/settle with service participants –Operator Wireless LAN Support for ensemble devices –Cell Phone + Wall Camera & Display

67. 67 Outline What is this Course About? Technology Trends Evolution of the Internet Business Trends Implications and Issues Summary and Conclusions

68. 68 What will be the Next Generation of Driving Applications? Location-aware/context-aware information delivery and presentation –Extends UniIn-Box: loc-based, exploits calendar info –Mediation to translate formats IP Telephony, Packet VoD, Teleconferencing –Streaming media, multicast-based –Bandwidth, latency, jitter, lose rate constraints –Clearinghouse provisioning Event Delivery for Distributed Applications –Performance/reliability constrained messaging –Management of Content Delivery Networks, Distributed Service architecture? Interactive Games? Distributed Storage (OceanStore)? Telemetry?

69. 69 What Will Be the Next Generation Operational Environment? Virtual Operators/Service Provider (VOSP) –Provide service to end users with no server/network infrastructure of own –Independent “Path” providers (e.g., ISPs) and Server providers (e.g., Internet Data Centers) –Many-to-many relationship between VOSP and Path/Server Providers Confederated Service Provider –Service-level peering: sharing of paths and servers to deploy end-to-end service with performance and reliability constraints Note: Akamai runs “the world’s largest service network” without owning a network!

70. 70 Alternative Operational Environments Confederation Model –Providers share (limited) information about topology, server location, path performance –Cooperatively collect internal information and share Overlay Model –Reverse-engineer topology and intra-cloud performance –Collection done by brokers outside of the cloud SLAs, Verification, Maintenance of Trust Relationships different in the two models Is there an operational/performance advantage to the Confederation Model?

71. 71 Open Issues/Questions Traditional Overlay Networks –Server (“Application Level Router”) Placement »For scaling, reliability, load balancing, latency »Where? Network topology discovery: WAN Core, Metro/Regional, Access Networks –Choice of Inter-Server “Paths” »For server-to-server latency/bandwidth/loss rate »Predictable/verifiable network performance (intra-ISP SLA) –Redirection Mechanisms »Random, round-robin, load-informed redirection »Net vs. server as bottleneck

72. 72 Open Issues/Questions Performance-constrained Service Placement –Separation of Service, Server, Service Path »Assume “Server Centers” known, can be “discovered” (how does OceanStore deal with this?), or register with a Service Placement Service (SPS) »How is Service named, described, performance constraints expressed, and registered? »How is app/service-specific performance measured and made known to Service Placement Service? –Brokering between Server Centers and Service Creator, Path Provider and Service Creator If core network bandwidth becomes infinite and “free”, does it matter where services are placed? –Latency reduction vs. economies of centralized management

73. 73 Emerging Reference Architecture Path Provider (ISP Cloud) Server Center Provider Perf Measurement Service Service Placement Service SLAsVerify Path BrokerServer Broker Server Registration Advertisement Registration Service Registration Service Redirection Distributed Application Pricing Service Constraint Specification Adapt Marshal Resources Based on Economic Constraints

74. 74 Methodological Framework Problem: performing scaled, wide-area networking studies in the current Internet environment Possible Solution: Wide-area Network Emulation –Virtual WAN (VWAN) on Large-scale Multicomputer Testbeds –Build operational model on top of VWAN »Traffic generation and measurement infrastructure »Build Confederation and Overlay operational models »What part of mechanisms for measurement, negotiation, registration, redirection, etc. the same and which are different?

75. 75 Outline What is this Course About? Technology Trends Evolution of the Internet Business Trends Implications and Issues Summary and Conclusions

76. 76 Access Networks Core Networks Connectivity and Processing Transit Net Private Peering NAP Public Peering Internet Datacenter PSTN Regional Wireline Regional Voice Cell Cable Modem LAN Premises- based WLAN Premises- based Operator- based H.323 Data RAS Analog DSLAM H.323

77. 77 Challenges for Converged Networks Services spanning access networks, to achieve high performance and manage diversity of end devices Not about specific Information Appliances Builds on the New Internet: multiple application- specific “overlay” networks, with new kinds of service-level peering Pervasive support for services within “intelligent” networks –Automatic replication –Document routing to caches –Compression & mirroring –Data transformation

78. 78 Managing Edge Versus Core Services Wide-area bandwidth efficiency Increasing b/w over access networks, but impedance mismatch between core and access nets Fast response time (and more predictable) Opportunity to untegrate localized content Associated with client (actually ISP), not server Examples: –Caching: exploits response time, b/w efficiency, high local b/w –Filtering: form of local content transformation –Internet TV: b/w efficiency, high local b/w, predictable response –Transformation: adapt content for end user/diverse access devices –Software Rental: sxploits high local b/w –Games, chat rooms, ….

79. 79 Yielding a New Research Agenda New Definition of “Quality of Service” –Perceived quality depends on services in the network –Manage caches, redirection, NOT bandwidth –Enable incorporation of localized content Bandwidth Issues –Tier 1 ISP backbones rapidly moving towards OC 192 (9.6 gbs!) –Better interconnection: hops across ASs decreasing over time –Emerging broadband access networks: cable, DSL,... –End-to-end latency/server load dominate performance Supporting Old Services in the New Internet –IP Multicast, DNS, … –Rethinking the End-to-End Principle –Service/content-level peering, just like routing-level peering –Secure end-to-end connection compatible with service model?