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01CourseOverview

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									  Berkeley-Helsinki Summer Course
    Lecture #1: Course Overview

                      Randy H. Katz
                Computer Science Division
Electrical Engineering and Computer Science Department
                 University of California
                Berkeley, CA 94720-1776

                                                         1
                    Outline

•   Course Content
•   Technology Trends
•   Evolution of the Internet
•   Business Trends
•   Implications and Issues
•   Summary and Conclusions




                                2
                    Outline

•   Course Content
•   Technology Trends
•   Evolution of the Internet
•   Business Trends
•   Implications and Issues
•   Summary and Conclusions




                                3
  What is this Course About?

• Emerging, yet still developing, view of a new
  kind of communications-oriented middleware
   – 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

                                                                  4
                    Course Lectures

Berkeley, 29-30 May                 Espoo, 9, 11 June
•   Course Overview                 •   IP QoS
•   Telecomm Service Architecture   •   SLAs and Clearing Houses
•   Middleware Architecture         •   Context Awareness
•   CORBA/OMG                       •   Introspection & Adaptation
•   UMTS/3GPP                       •   Security in Mobile Computing
•   IP Mobility                     •   Service Discovery Protocols
•   Net Measurement & Monitoring    •   Content Distribution Protocols
•   Internet Economics              •   Wrap-up Summary




                                                                         5
           A Possible Service
             Architecture
         Prototype Applications: Universal In-Box,
          Context-Aware UI, Group Collaboration
Context-Awareness Services: Activity Tracking/Coordination,
         Preferences Specification/Interpretation
           Adaptation Services: Introspection,
        Tacit Information Extraction/Organization

Wide-Area Services: Discovery, Mobility, Trust, Availability

         Performance Measurement and Monitoring

                ―Core‖ Wide-Area Network

                  Edge/Access Networks

                                                               6
                  Nokia’s mPlatform
                    Architecture
  Operational     Common Enabling Application Functions
   Support
                    Presentation     Navigation        Session
 Provisioning         Manager         Manager          Manager
                     Operator        Notification   Personalization
  Self-Care           Manager         Manager          Manager
                   Audit Manager      Security         Scenario
Operator Care         (Billing)       Manager          Manager

  Billing Data    Access Functions
   Collection
                   Subscriber       Subscriber      Service
Sys Monitoring    Access Control Authentication Access Control
                             Process       WAP & PDA
Perf Monitoring             Handling          Proxy
                                      Network           Load
  Statistics         Firewall
                                     Connectivity     Balancing
                                                                      7
                       ICEBERG Architecture
Access Network                                                                 CA
     Plane              PSTN              GSM     Pager                        PR
                                                                               PAC
                                                                               APC
                            IAP IAP IAP           IAP    IAP                   NMS

ICEBERG
                       SF iPOP               A            NY iPOP
Network
   Plane         IAP
                                                               • iPOP: Clustered
             SF iPOP                  B           NY iPOP        computing environ.
                                                               • Call Agent: handles
                                                                signaling, one per
                                 Clearing House                 device per call party
 ISP Plane             ISP1           ISP2        ISP3
• 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
                                                                                 8
           One Operator’s Viewpoint
      Pricing                                       Distribution
     Structure             Marketing & Sales
                                                        Packaging
Customer         Billing
 Service
              Charging                       Apps     3rd Party
       HLR
                                                        Apps
              Support Systems                  Services         Content

                             Service Domain

                               Data Center

                       Data Storage       Processing Cap

                                      Local Radio
        BS                              Access
       BS      Radio Access
                                                     Core Network
     Spectrum    Network
       QoS Cap                                           Capacity
                                   Transport            On-Demand
               Capacity
              On-Demand                                                   9
                    Outline

•   Course Content
•   Technology Trends
•   Evolution of the Internet
•   Business Trends
•   Implications and Issues
•   Summary and Conclusions




                                10
           Technology Trends

• Computing
   – Convergence, Divergence, Scale
• Networks
   – Internet vs. Telephone Network
   – Wireless/Mobile Access
• Services
   – E-commerce, M-commerce, Content
• Architecture
   – Integrated (―Closed‖) vs. Composed (―Open‖) Content,
     Distribution, Access Architecture
   – Managed vs. Overlay Networks and Services
   – Competitive vs. Cooperative Service Providers

                                                            11
                                Convergence?
 First Color TV   HBO Launched,                Interactive TV,
Broadcast, 1953       1972                          1990




 Telephone,
    1876
                             Early Wireless    Handheld Portable
                              Phones, 1978       Phones, 1990




                                                                                Pentium
                                                                                PC, 1993
                  Computer   First PC   IBM    Apple  Apple      IBM
                  + Modem     Altair,    PC,   Mac, Powerbook, Thinkpad,
                    1957       1974     1981   1984    1990      1992
                                                                            Apple
   Eniac, 1947
                                                                           Newton,
                                                                            1993
                                                               HP
                                                            Palmtop,
                                                              1991
                                                                                           Red Herring, 10/99   12
                                       Divergence!

Atari Home
Pong, 1972                                                                   Game Consoles
                                                                      Personal Digital Assistants
                                                                     Digital VCRs (TiVo, ReplayTV)
                                                                             Communicators
                                                                           Smart Telephones
                                                                          E-Toys (Furby, Aibo)
    Pentium         Network          Free          Sega      Internet-enabled
   PC, 1993        Computer,       PC, 1999     Dreamcast,    Smart Phones,
                     1996                          1999            1999

              Pentium II
               PC, 1997

                      Apple
                    iMac, 1998


                                Palm VII       Proliferation of diverse
                               PDA, 1999
                                           end devices and access networks                              13
                                                                                   Red Herring, 10/99
        Convergence: Post-PC

•   Not about gadgets or access technologies
•   About services and applications
•   Increasing, not decreasing, diversity
•   Enabled by computing embedded in
    communications fabric




                                               14
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


                                                    15
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




                                                  16
   Societal-Scale Systems
  New System Architectures                             Massive Cluster



   New Enabled Applications
                                                             Clusters
                                          Gigabit Ethernet



    Diverse, Connected, Physical,
            Virtual, Fluid  ―Server‖
                                         Scalable, Reliable,
                              ―Client‖   Secure Services
                Information
                Appliances




   MEMS
BioMonitoring
                                                                         17
           What is the Internet?
     “It’s the TCP/IP Protocol Stack”

          Applications                            • Applications
                                                     – Web
          Middleware                                 – Email
           Services                                  – Video/Audio
                        Transport Services and
―Narrow
             TCP/IP
                       Representation Standards   • TCP/IP
 Waist‖                  Open Data Network
                           Bearer Service         • Access Technologies
            Network                                  – Ethernet (LAN)
          Technology                                 – Wireless (LMDS, WLAN,
           Substrate                                   Cellular)
             Access                                  – Cable
                                                     – ADSL
          Technologies
                                                     – Satellite
Where is the next ―narrow waist‖?                                         18
            Telephony Evolution

• Mobility/Wireless driving end-to-end digitization of
  the telephony system
   – Shift towards IP-based infrastructure (e.g., Motorola + CISCO)
• 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‖)

                                                                      19
        Internet vs. Telephone Net

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

                                                                 20
               Wireless Access Technologies
                                  Wireless Communications

                 Consumer                                            Business




Residential    Cellular/PCS   Satellite       WLAN          Mobile Data    PMR/SMR       WPBX
 — WLL         — 2nd Gen      — DirecTV/PC    — 802.11      — ARDIS        — Moto iDen
 — LMDS         (GSM,         — Spaceway,     — HomeRF      — Mobitex        (Nextel)
 — MMDS          TDMA,         Teledesic      — BlueTooth   — Omnitracs
 — Satellite      CDMA)       — Globalstar,   — IrDA        — CDPD, GSM
 — HomeRF      — 3rd Gen       JSAT,          — HiPerLAN      SMS, Edge,
                (W-CDMA)       ICO                            GPRS, WAP
                                                            — NTT I-Mode
                                                            — Palm VII

     • Broadband Wireless data poised to take off
     • High degree of diversity among access technologies
     • Convergence of consumer and business needs
                                                                                            21
             Design Space of Terrestrial
               Wireless Performance
                Wired
Mbps   100
                                  ―Mobile Broadband            60 GHz
                                      Systems‖               100 m range
       10             Wireless
                     Local Area
       1             Networks                    ―Universal Mobile
                                              Telecomms Systems‖
                 Cordless                                 (UMTS)
       0.1

                                                 Cellular
       0.01
               Office or    Building    Stationary    Walking    Vehicle
                Room
                     Indoors                          Outdoors
                                                                           22
  Access Networks: One View
  (21 million I-Mode users?)
• Only 15% of personal consumer devices will be
  able to access Internet within 5 years
  (embedded micro-browser and e-mail client)
   – 5 years: Internet access remains a niche for mobile access
   – 10 years: Internet access becomes ubiquitous
   – Placed-based vs. passenger-based vs. personal access
• BUT 50% of US hotel rooms will have Internet
  access within 5 years!
• Situational and time sensitive services will
  dominate (directions, maps, e-mail, weather
  information, traffic updates)
• 2007: 7 million autos equipped with driver
  information systems
                                    Jupiter Communications: ―Internet Everywhere‖   23
    Cellular Services Most Often
              Requested
       After basic wireless telephony service

•   Call Forwarding                 37%
•   Paging                          33%
•   Internet/E-Mail                 24%    Data
•   Traffic/Weather                 15% Applications
•   Conference Calling              13%
•   News                            3%



                           Source: CTIA Web Page
                           Peter D. Hart Research Associates, March 1997   24
                          Satellite Technology
      Back Link
   (Satellite Phone)             Satellite Broadcast Networks                     Characteristics
                                                                                  . Broadcast
                                                                                  . Bandwidth on-demand
                                                      Media Stream
                                                                                  . Ubiquitous
     Request                                                                NOC




                                  Request                                     Internet

Media Browser
                              Back Link Channel
                           (Cellular / PCS Network)
                                                                                                  Multimedia
                                                                             Request             Data Sources


                 Media Browser
                                                             Back Link Channel
                                                            (Phone, Cable Line)
                                            Media Browser                                                 25
       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

                                                                           26
                    Outline

•   Course Content
•   Technology Trends
•   Evolution of the Internet
•   Business Trends
•   Implications and Issues
•   Summary and Conclusions




                                27
                Internet Evolution

   ARPANet         TCP/IP   NSFNet    Deregulation & ISP
   SATNet                            Commercialization ASP
    PRNet                                   WWW        AIP
1965            1975         1985            1995             2005




       Web Hosting            Application Hosting
       Multiple ISPs          ASP: Application Service Provider
       Internet2 Backbone     AIP: Application Infrastructure
       Internet Exchanges     Provider (e-commerce tookit, etc.)
                                                                     28
Network “Cloud”




                  29
Regional Nets + Backbone


                 Regional
Regional                          Regional
                   Net
  Net                               Net


                     Backbone
                                  Regional
Regional
                 Regional           Net
  Net
                   Net

           LAN     LAN      LAN



                                             30
      Backbones + NAPs + ISPs


                                   ISP
        ISP


          NAP
                                  NAP         ISP
ISP                  Backbones

        Business                 Consumer
          ISP                      ISP

  LAN     LAN      LAN              Dial-up


                                                    31
Core Networks + Access Networks
   DSL                               Cable
 Always on                         Head Ends


                                       @home
                 Covad


                             Core       NAP          ISP
                   NAP
   Cingular                Networks
                                                       Satellite
                                                       Fixed Wireless
Cell     Cell
    Cell          Sprint                 AOL

           LAN     LAN       LAN           Dial-up


                                                                  32
       Computers Inside the Core
   DSL                             Cable
 Always on                       Head Ends


                                     @home
                 Covad


                   NAP
                                      NAP          ISP
   Cingular
                                                     Satellite
                                                     Fixed Wireless
Cell     Cell
    Cell          Sprint               AOL

           LAN     LAN     LAN           Dial-up


                                                                33
                    Outline

•   Course Content
•   Technology Trends
•   Evolution of the Internet
•   Business Trends
•   Implications and Issues
•   Summary and Conclusions




                                34
               Emerging Internet Service
                    Business Model
                                                 Applications
                                            (Portals, E-Commerce,
                                              E-Tainment, Media)

                                         Appl Infrastructure Services
    AIP                                     (Distribution, Caching,
    ISV                                       Searching, Hosting)

                                          Application-specific Servers
    ASP                                (Streaming Media, Transformation)
  Internet
Data Centers                                  Application-specific
                                               Overlay Networks
                                        (Multicast Tunnels, Mgmt Svrcs)
    ISP                                        Internetworking
   CLEC        Global Packet Network            (Connectivity)
                                                                        35
               A New Kind of Internet
                            Customer J
Web Site Caching                                   PC, Set-top Box.
Comparison Shopping      Terminal Equipment &      Smart Phone, Game
Interactive TV Guide       Access Network          Console, E-toys
Local Ad Insertion
Streaming Media
                             Applications          Web, E-mail, Chat,
    Application                                    E-commerce,
     Services                                      E-tainment
                        Regional Communications    ISP
                                                   Web Hosting
Server ―Platform‖          Server Computing
ISP Caching                                       Infrastructure
Search Engine                                        Services
                       Wide-Area Communications
                                                   High Performance
                                                   Backbone         36
   Open vs. Closed Access to Services
 Covad     Time/Warner
                                                       Cable, DSL, MMDS,
  DSL       Roadrunner    AT&T Cable      Access        LMDS, Satellite
            AOL Dial-up
 CNCX          AOL         @Home       Local Network         ISP
                                        Management
                                         Routing &         Backbone
Williams       AOL         @Home
                                        Distribution       Provider

 Web       AOL/Netscape     Excite        Content          Portal
           Time/Warner                                    Web Sites


   • 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
                                                                      37
           Context for Cooperation
           Among Service Providers
• Huge Expense of 3G Mobile Telecomms Infrastructures
   – European spectrum auctions: 50 billion ECU and counting
   – Capital outlays likely to match spectrum expenses, all before the first
     ECU of revenue!
   – Wireless operators in complex web of business relationships and partial
     ownerships of networks around the world
• Compelling motivation for collaborative deployment of
  wireless infrastructure
   – Happening already several places in Europe & Asia
• Same for cooperative service infrastructure?
   – Mobile Virtual Network Operator (MVNO)
   – Internet transport providers vigorously complete
   – But some cooperation also emerging: Content Dissemination Alliances
                                                                           38
                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




                                                                       39
     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

                                                     40
   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




                                                  41
              Business as Usual:
             Vertical Integration

PBMS                                                  Sprint

         Access                           Access
         Network                          Network
         Backhaul                         Backhaul
         Network                          Network
                      PSTN Network
               (Multiservice Provider today)
                         Internet
               (Multiservice Provider today)

  • Each operator owns own frequencies, cell sites,
    backhaul network
                                                          42
               Business Unusual:
             Horizontal Competition
                           Sprint ―leases‖
                         frequencies from
―Mom&Pop‖                PBMS, on-demand,
 Cell Site              based on the density
Operators                of its subscribers


                         Access Network

                         Access Network
             Backhaul                          Backhaul
             Network                           Network
                            PSTN
                           Network
                           Internet
                                                          43
                       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
• Support for confederated/virtual devices
   – Mini-BS for cellular/data + WLAN for high rate data

                                                                   44
                    Outline

•   Course Content
•   Technology Trends
•   Evolution of the Internet
•   Business Trends
•   Implications and Issues
•   Summary and Conclusions




                                45
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?                                          46
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!


                                                                       47
         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?


                                                                    48
         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



                                                                 49
           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

                                                                        50
    Emerging Reference Architecture
                Distributed Application
 Constraint        Marshal Resources
Specification Based on Economic Constraints       Adapt

           Service Registration                  Service
                                               Redirection
         Service Placement Service               Pricing
    Path Broker         Server Broker            Service

 Perf Measurement Service            Server Registration
                                               Advertisement
Verify                 SLAs                     Registration
 Path Provider (ISP Cloud)
  Path Provider (ISP Cloud)       Path Provider (ISP Cloud)
                                   Path Provider (ISP Cloud)
   Path Provider (ISP Cloud)         Server Center Provider
                                                               51
      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?




                                                                  52
                    Outline

•   Course Content
•   Technology Trends
•   Evolution of the Internet
•   Business Trends
•   Implications and Issues
•   Summary and Conclusions




                                53
 Challenges for the Post-PC Era

• 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


                                                        54
              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, ….                                               55
                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?
                                                                        56

								
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