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


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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


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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


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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


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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


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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


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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?

1 berkeley-helsinki summer course lecture #1: course overview randy h. katz computer science...

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