1 berkeley-helsinki summer course lecture #1: course overview randy h. katz computer science...
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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
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Outline
• Course Content• Technology Trends• Evolution of the Internet• Business Trends• Implications and Issues• Summary and Conclusions
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Outline
• Course Content• Technology Trends• Evolution of the Internet• Business Trends• Implications and Issues• Summary and Conclusions
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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
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Course Lectures
Berkeley, 29-30 May• Course Overview• Telecomm Service Architecture• Middleware Architecture• CORBA/OMG• UMTS/3GPP• IP Mobility• Net Measurement & Monitoring• Internet Economics
Espoo, 9, 11 June• IP QoS• SLAs and Clearing Houses• Context Awareness• Introspection & Adaptation• Security in Mobile
Computing• Service Discovery Protocols• Content Distribution
Protocols• Wrap-up Summary
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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
A Possible Service Architecture
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Statistics
Perf Monitoring
Sys Monitoring
Billing DataCollection
Operator Care
Self-Care
Provisioning
Operational Support
Nokia’s mPlatform Architecture
FirewallNetwork
Connectivity
ProcessHandling
SubscriberAccess Control
LoadBalancing
WAP & PDAProxy
SubscriberAuthentication
ServiceAccess Control
Access Functions
Audit Manager(Billing)
OperatorManager
PresentationManager
SecurityManager
NotificationManager
NavigationManager
ScenarioManager
PersonalizationManager
SessionManager
Common Enabling Application Functions
Applica
tion In
terfa
ce
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PSTN GSM PagerAccess Network
Plane
ICEBERG Network
Plane
ISP Plane
A
B
IAP IAP
ISP1 ISP2 ISP3
IAP
NY iPOP
NY iPOP
SF iPOP
Clearing House
ICEBERG Architecture
IAP IAP IAP
PRCA
PACAPCNMS
• 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
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BS
One Operator’s Viewpoint
Radio AccessNetwork
Core Network
Transport
BSSpectrum
QoS Cap
Local RadioAccess
CapacityOn-DemandCapacity
On-Demand
Service Domain
Data Center
Data Storage Processing Cap
Support Systems Services
HLRCharging Apps 3rd Party
AppsContent
Marketing & SalesPricing
StructureDistribution
PackagingCustomerService
Billing
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Outline
• Course Content• Technology Trends• Evolution of the Internet• Business Trends• Implications and Issues• Summary and Conclusions
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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
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Convergence?
Eniac, 1947
Telephone,1876
Computer+ Modem
1957
Early WirelessPhones, 1978
First Color TVBroadcast, 1953
HBO Launched, 1972
Interactive TV, 1990
Handheld PortablePhones, 1990
First PCAltair,1974
IBMPC,
1981
AppleMac,1984
ApplePowerbook,
1990
IBMThinkpad,
1992
HPPalmtop,
1991
AppleNewton,
1993
PentiumPC, 1993
Red Herring, 10/99
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Game ConsolesPersonal Digital Assistants
Digital VCRs (TiVo, ReplayTV)
CommunicatorsSmart Telephones
E-Toys (Furby, Aibo)
Divergence!
PentiumPC, 1993
Atari HomePong, 1972
AppleiMac, 1998
Pentium IIPC, 1997
Palm VIIPDA, 1999
NetworkComputer,
1996
FreePC, 1999
SegaDreamcast,
1999
Internet-enabledSmart Phones,
1999
Red Herring, 10/99
Proliferation of diverseend devices and access networks
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Convergence: Post-PC
• Not about gadgets or access technologies
• About services and applications• Increasing, not decreasing, diversity• Enabled by computing embedded in
communications fabric
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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
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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
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Societal-Scale Systems
“Client”
“Server”
Clusters
Massive Cluster
Gigabit Ethernet
New System Architectures
New Enabled ApplicationsDiverse, Connected, Physical,
Virtual, Fluid
MEMSBioMonitoring
Scalable, Reliable,Secure Services
InformationAppliances
18Where 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
AccessTechnologies
“NarrowWaist”
Transport Services andRepresentation Standards
Open Data NetworkBearer Service
MiddlewareServices
NetworkTechnologySubstrate
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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”)
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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
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Wireless Access Technologies
• Broadband Wireless data poised to take off• High degree of diversity among access technologies• Convergence of consumer and business needs
Wireless Communications
Consumer Business
Residential Cellular/PCS WPBXMobile DataWLAN— 2nd Gen (GSM, TDMA, CDMA)— 3rd Gen (W-CDMA)
— ARDIS— Mobitex— Omnitracs— CDPD, GSM SMS, Edge, GPRS, WAP— NTT I-Mode— Palm VII
— 802.11— HomeRF— BlueTooth— IrDA— HiPerLAN
Satellite— DirecTV/PC— Spaceway, Teledesic— Globalstar, JSAT, ICO
PMR/SMR— Moto iDen (Nextel)
— WLL— LMDS— MMDS— Satellite— HomeRF
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“Universal MobileTelecomms Systems”
(UMTS)
“Mobile BroadbandSystems”
60 GHz100 m range
WirelessLocal AreaNetworks
Design Space of Terrestrial Wireless Performance
Mbps
0.01
0.1
1
10
100
Cellular
Cordless
Wired
Office orRoom
Building
Indoors
Stationary Walking
Outdoors
Vehicle
23Jupiter Communications: “Internet Everywhere”
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
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DataApplications
Source: CTIA Web PagePeter D. Hart Research Associates, March 1997
After basic wireless telephony service
Cellular Services Most Often Requested
• Call Forwarding 37%• Paging 33%• Internet/E-Mail 24%• Traffic/Weather 15%• Conference Calling 13%• News 3%
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Back Link Channel(Phone, Cable Line)
Back Link Channel(Cellular / PCS Network)
MultimediaData Sources
Satellite Broadcast Networks
Internet
NOC
Back Link (Satellite Phone)
Media Browser
Media Browser
Media Browser
Media Stream
Request
Request
Request
Characteristics. Broadcast . Bandwidth on-demand. Ubiquitous
Satellite Technology
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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
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Outline
• Course Content• Technology Trends• Evolution of the Internet• Business Trends• Implications and Issues• Summary and Conclusions
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Internet Evolution
Web HostingMultiple ISPsInternet2 BackboneInternet Exchanges
Application HostingASP: Application Service ProviderAIP: Application InfrastructureProvider (e-commerce tookit, etc.)
ARPANetSATNetPRNet
TCP/IP NSFNet Deregulation &Commercialization
1965 1975 1985 1995 2005
WWW
ISPASPAIP
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Network “Cloud”
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RegionalNet
Regional Nets + Backbone
RegionalNet Regional
Net
RegionalNet Regional
Net
RegionalNet
Backbone
LAN LANLAN
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ISP
Backbones + NAPs + ISPs
ISP
ISPISP
BusinessISP
ConsumerISP
LAN LANLAN
NAPNAP
Backbones
Dial-up
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CoreNetworks
Covad
Core Networks + Access Networks
@home
ISPCingular
Sprint AOL
LAN LANLAN
NAP
Dial-up
DSLAlways on
NAP
CableHead Ends
CellCell
Cell
SatelliteFixed Wireless
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Covad
Computers Inside the Core
@home
ISPCingular
Sprint AOL
LAN LANLAN
NAP
Dial-up
DSLAlways on
NAP
CableHead Ends
CellCell
Cell
SatelliteFixed Wireless
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Outline
• Course Content• Technology Trends• Evolution of the Internet• Business Trends• Implications and Issues• Summary and Conclusions
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Global Packet Network Internetworking(Connectivity)
ISPCLEC
Emerging Internet Service Business Model
Application-specificOverlay Networks
(Multicast Tunnels, Mgmt Svrcs)
Applications(Portals, E-Commerce,
E-Tainment, Media)
Application-specific Servers(Streaming Media, Transformation)ASP
InternetData Centers
Appl Infrastructure Services(Distribution, Caching,
Searching, Hosting)
AIPISV
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ApplicationServices
Web Site CachingComparison ShoppingInteractive TV GuideLocal Ad InsertionStreaming Media
A New Kind of Internet
InfrastructureServices
Terminal Equipment &Access Network
PC, Set-top Box.Smart Phone, GameConsole, E-toys
Server Computing
Web HostingServer “Platform”ISP CachingSearch Engine
Applications Web, E-mail, Chat, E-commerce,E-tainment
Regional Communications ISP
Wide-Area Communications High PerformanceBackbone
Customer
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Content
Open vs. Closed Access to Services
AT&T Cable
@Home
@Home
Excite
Cable, DSL, MMDS,LMDS, Satellite
ISP
BackboneProvider
PortalWeb Sites
Routing &Distribution
Local NetworkManagement
Access
Time/WarnerRoadrunnerAOL Dial-up
AOL
AOL
AOL/NetscapeTime/Warner
CovadDSL
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
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Context for CooperationAmong 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
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Any Way to Builda 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
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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
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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
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Internet(Multiservice Provider today)
PSTN Network(Multiservice Provider today)
BackhaulNetwork
AccessNetwork
BackhaulNetwork
AccessNetwork
Business as Usual:Vertical Integration
• Each operator owns own frequencies, cell sites, backhaul network
PBMS Sprint
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Access Network
Business Unusual: Horizontal Competition
Internet
PSTNNetwork
BackhaulNetwork
Access Network
BackhaulNetwork
Sprint “leases”frequencies from
PBMS, on-demand,based on the density
of its subscribers
“Mom&Pop”Cell Site
Operators
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VirtualOperator
• 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
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Outline
• Course Content• Technology Trends• Evolution of the Internet• Business Trends• Implications and Issues• Summary and Conclusions
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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?
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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!
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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?
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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
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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
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Emerging Reference Architecture
Path Provider (ISP Cloud)Path Provider (ISP Cloud)Path Provider (ISP Cloud)Path Provider (ISP Cloud)Path Provider (ISP Cloud)Server Center Provider
Perf Measurement Service
Service Placement Service
SLAsVerify
Path Broker Server Broker
Server RegistrationAdvertisement
Registration
Service Registration ServiceRedirection
Distributed Application
PricingService
ConstraintSpecification Adapt
Marshal ResourcesBased on Economic Constraints
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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?
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Outline
• Course Content• Technology Trends• Evolution of the Internet• Business Trends• Implications and Issues• Summary and Conclusions
54
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
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Managing Edge VersusCore 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, ….
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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?