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

Outline

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

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Outline

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

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

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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

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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

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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

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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

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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

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Nokia’s Mobile World View

NetworkEnvironment

Identity/Addressing

Interaction

InternetIntranet2G/3G

MessagingBrowsingRich Call

URLEmail

Phone #

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Nokia’s Mobile Service Matrix

Content

InformationEntertainment

NewsBanking & Finance

Buy & SellTravelMusic

TVLifestyle

FunGames

AstrologyDating

Comms

Messaging

E-Mail

FAX

Rich Call

Productivity

Organizers

Personal Assistants

Tools

Misc

Business

Intranet &ExtranetAccess

Info Mgmt

EnterpriseComms

VPNs

Telematics

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Nokia’s Mobile Internet “Business Architecture”

Service Providers

EndUsers Developers

ContentProviders

Consumption

User InterfaceApplications

Rich Call Browsing Msg

Middleware

OS NetworkHardware

Connection

Application GatewaysRich Call Browsing Msg

Middleware

OS NetworkHardware

Consumption

ApplicationsRich Call Browsing Msg

Middleware

OS NetworkHardware

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Application Programming Interface

Application LayerOther and 3rd 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 LayerApp Framework and UI Support

SDK Interfaces Network Interface

SDK Libraries Network Protocols

App Protocols

Platform Applications Interfaces

Platform LayerI/O Drivers

I/O Hardware

OS Core

Processors & Memory

Link Layer Drivers

Network Hardware

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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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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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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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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

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Outline

• What is this Course About?• 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/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

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Internet Growth

0

40

80

120MillionServers

Annual Growth Rate > 50%

0

50

100

150

200Million

U.S. Surfers

Annual Growth Rate > 20%

The Industry Standard, 2 July 2001

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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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Automobiles663 Million

Telephones1.5 Billion

Electronic Chips30 Billion

X-Internet

“X-Internet” Beyond the PC

Forrester Research, May 2001

93Million

407 Million

Internet Computers

Internet UsersToday’s Internet

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“X-Internet” Beyond the PC

Forrester Research, May 2001

0

5000

10000

15000Millions

Year

XInternet

PCInternet

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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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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

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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

911.5

17

8.513.5

40.5

Ring Tone

Games

Entertain

Database

Info

Transactions

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24

2012

8

27

Unknown

<20

20- 24

25- 29

30- 34

35- 39

>39

Applications Used User Ages

Economist Magazine, 13 Oct 2001

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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

30Where 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 (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”)

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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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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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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

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

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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

SRI940

UCLASigma 7

UCSBIBM 360

UtahPDP 10

IMPs

BBN team that implementedthe interface message processor

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ARPANet Evolves into Internet

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

39

40

41

Parallel BackbonesQwest IP Backbone (Late 1999)Digex BackboneGTE Internetworking Backbone

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43

Network “Cloud”

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RegionalNet

Regional Nets + Backbone

RegionalNet Regional

Net

RegionalNet Regional

Net

RegionalNet

Backbone

LAN LANLAN

45

ISP

Backbones + NAPs + ISPs

ISP

ISPISP

BusinessISP

ConsumerISP

LAN LANLAN

NAPNAP

Backbones

Dial-up

46

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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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.”

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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

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Isolatedmulticast

clouds

Traditionalunicastpeering

multicastcloud

multicastcloud

multicastcloud

multicastcloud

multicastcloud

Application-Specific Overlays

E.g., solve the multicast management and peering problems by moving up the protocol stack

Steve McCanne

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Application-Level Servers/Routers

Solve the multicast management and peering problems by moving up the protocol stack

Steve McCanne

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Outline

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

53

Global Packet Network Internetworking(Connectivity)

ISPCLEC

Layerized 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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• 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

ServerLoad Balancing

Advanced TrafficManagement

• Rapid problem diagnosis/ isolation

• Service level measurement

• Multi-tier resource monitoring

•Preferential Services

•Resource Provisioning

•Self-tuning

•Problemprevention

Service Level Control

Chris Morino, Resonate

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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

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Competition vs. Cooperation

• Internet Service Providers: Competition– Peering for packet transport: BGP protocol– Charging based on traffic volumes

ISP A

ISP B

Hot PotatoRouting

PeeringPoint

PeeringPoint

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

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

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

66

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– Operator Wireless LAN

• Support for ensemble devices– Cell Phone + Wall Camera & Display

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Outline

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

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?

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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!

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

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

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

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

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

Outline

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

76

AccessNetworks

Core Networks

Connectivity and Processing

Transit Net

Transit Net

Transit Net

PrivatePeering

NAP

PublicPeering

InternetDatacenter

PSTNRegional

WirelineRegionalVoiceVoice

CellCell

Cell

CableModem

LAN

LAN

LAN

Premises-based

WLAN

WLAN

WLAN

Premises-based

Operator-based

H.323Data

Data

RAS

Analog

DSLAM

H.323

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

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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?