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SAHARA First Winter Retreat16-18 January 2002

Randy H. Katz, Anthony Joseph, Ion StoicaComputer Science Division

Electrical Engineering and Computer Science DepartmentUniversity of California, Berkeley

Berkeley, CA 94720-1776

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Retreat Goals &Technology Transfer

UC Berkeley Project Team Industrial CollaboratorsGovernment Sponsors

Friends

PeopleProject Status

Work in ProgressPrototype Technology

Early Access to TechnologyPromising Directions

Reality CheckFeedback

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Who is Here (Industry)• AT&T Research

– Yatin Chawathe

• Ericsson Research– Per Johansson (VIF)– Tony Johansson– Martin Korling

• HRL– Son Dao

• Keynote Systems– Chris Overton

• Microsoft Research– Venkat Padmanabhan– Lili Qui– Helen Wang

• Nokia/Univ. Helsinki– Kimmo Raatikainen

• Nortel Networks– Tal Lavian (PhD student)– Ben Warren

• NTTDoCoMo– Shoji Kurakake– Takashi Suzuki (VIF)

• Siemens– Markus Wischy

• Sprint ATL– Chen-nee Chuah– Bryan Lyles– Timothy Roscoe (VIF)

• Stanford University– Peter Danzig

Italics indicates Ph.D. from BerkeleyVIF=Visiting Industrial Fellow

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Who is Here (Berkeley)

• Professors– Anthony Joseph– Randy Katz– Ion Stoica

• Postdocs– Kevin Lai

• Technical & Admin Staff– Bob Miller– Keith Sklower– Glenda Smith

• Grad Students– Sharad Agarwal– Matt Caesar– Yan Chen– Weidong Cui

• Grad Students– Steve Czerwinski– Yitao Duan– Ling Huang– Karthik Lakshminarayanan– Sridhar Machiraju– Morley Mao– George Porter– Bhaskar Raman– Anantha Rajagoplala-Rao– Mukund Seshadri– Jimmy Shih– Lakshmi Subramanian– Ben Zhao– Shelley Zhuang

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Retreat Purpose• First full SAHARA retreat

– Project launched 1 July 2001– Introduce project concept and goals

• “Generation after next” networks– Software “agents,” not protocols– Converged data and telecommunications networks– Heterogeneous access plus core networks

• Emerging network-aware distributed architecture

– Confederation vs. brokering in service provisioning– Exploiting network structure-awareness

• Industrial feedback and directions– Real-world networking problems/limitations– Helping us do relevant research at Internet-scale

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Plan for the Retreat

• Wednesday, 16 January 2002– 1200-1330 Lunch– 1330-1500 Retreat Overview and Introductions

» Retreat Overview, Randy Katz» Sahara Project Overview, Randy Katz» AON Overview, Ion Stoica

– 1500-1530 Break– 1530-1700 Sahara Architecture Design Review and

Discussion, Randy Katz– 1700-1800 Graduate Student Panel Session, “How to

Do Internet-Scale Research in a University?” Randy Katz, Moderator

– 1800-1930 Dinner (Joint with ROC Retreat)– 1930-2100 Industry Panel Session, “Industrial

Strength Internet Services” (Joint with ROC Retreat)

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Plan for the Retreat

• Thursday, 17 January 2002– 0730-0830 Breakfast– 0830-1000 Tapestry Session (Joint with ROC Retreat)

» Tapestry Implementation and Status (Ben Zhao)» Dynamic Management Algorithms for Tapestry (Kris Hildrun)» Attenuated Bloom Filters for Reducing Routing Stretch (Sean

Rhea)– 1000-1030 Break– 1030-1200 AON Design Review, Ion Stoica– 1200-1300 Lunch (Skiers box lunch, bus departs noon, pick-up 1545)– 1300-1600 Long Break– 1630-1800 SAHARA Research Highlight Talks

» Topological Properties of the Internet (Sharad Agarwal)» Geographical Properties of the Internet (Lakshmi)» Auction-based Resource Allocation (Matt Caesar/Weidong Cue)» Fault Tolerant Service Composition (Bhaskar Raman)

– 1800-1930 Dinner (Joint with ROC Retreat)– 1930-2100 Graduate Student Research Poster Session

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Plan for the Retreat

• Friday, 18 January 2002– 0730-0830 Breakfast– 0830-1000 Six Month Planning (Anthony Joseph)– 1000-1030 Break/Room Checkout/Photo Session– 1030-1200 Industrial Feedback– 1200-1300 Lunch– 1300-1700 Bus back to Berkeley

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Experimental SystemsResearch Methodology

• Analyze alternatives to select among approaches

Analyze &Design

Prototype

• Prototype selected alternatives to understand implementation complexities

• Repeat

Evaluate

• Evaluate existing system to discover bottlenecks

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BARWAN: 1995-1998Bay Area Research Wireless Access Network

High-tier

Low-tier

Satellite

High Mobility Low MobilityWide Area

Regional Area

Local Area

• Universal multimedia information access with mobility spanning residences, businesses, public/pedestrian, mobile/vehicular, national, and global regions– Session/Transport/Routing Mobility+Performance (Hari, Venkat, Seshan,

Katz)– Client-Proxy-Server Architecture (Fox, Gribble, Brewer)– Soft-state Streaming Media Gateways (Amir, McCanne)

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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

IAP IAP IAP

PRCA

PACAPCNMS

• Name Mapping Service: Maps ICEBERG unique ID service end point• Preference Registry/Personal Activity Coordinator: user profile/user tracking• APC service: creates transcoding datapath between endpoints

SF iPOP

• iPOP: Clustered computing environ.• Call Agent: handles signaling, one per device per call party

ICEBERG: 1998-2001Internet-based CorE Beyond thiRd

Generation

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ICEBERG Lessons

• Soft state enabled session establishment and maintenance (Helen Wang’s Ph.D.)

– Distributed not centralized session maintenance protocol to provide correctness and robustness

– Soft-state works well for tolerating transient component failures, network partitions, and exceptional conditions

• Clearinghouse architecture (Chen-nee Chuah’s Ph.D.)

– Cooperatively negotiated “soft QoS” across admin domains– Traffic-matrix admission control– Group policing for malicious flow detection

• Dynamic data transcoding (Several M.S. projects)– Operator + plus concept, extended to wide-area– Enables source/target data format independence/isolation– Rapid support for new devices (new device in 2 hrs!)– Universal In-box

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ICEBERG Prelude to SAHARA

• ICEBERG lives on top of multiple access networks (e.g., cellular, pager, PSTN)

• ICEBERG service provider places iPOP in each service region, executes on highly available clusters, links regions via multiple core network ISPs

• Interactions among alternative service providers not explicitly addressed

• Assumes a homogeneous ICEBERG-capable universe

What about cooperation and competition among service providers?

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Global Packet Network Internetworking(Connectivity)

ISPCLEC

Horizontal Service 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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SAHARA: 2001-2003

• Service• Architecture for• Heterogeneous• Access,• Resources, and• Applications

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Sahara Research Themes

• New mechanisms, techniques for end-to-end services w/ desirable, predictable, enforceable properties spanning potentially distrusting service providers– Tech architecture for service composition & inter-operation

across separate admin domains, supporting peering & brokering, and diverse business, value-exchange, access-control models

– Functional elements» Service discovery» Service-level agreements» Service composition under constraints» Redirection to a service instance» Performance measurement infrastructure» Constraints based on performance, access control,

accounting/billing/settlements» Service modeling and verification

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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

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Competition vs. Cooperation

• Wireless Operators: Cooperation– Telephone sessions span multiple providers– Well-defined roaming agreements among mobile

operators– Established methods for sharing revenue between

local access and transport providers– Context for Virtual Home Environment

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ServiceProvider Cooperation

• Expense of 3G Infrastructures – European spectrum auctions: 150 billion+ ECU – Capital outlays likely to match spectrum expenses– Complex web of biz relationships among operators

• Collaborative deployment of physical network infrastructure

• Service infrastructure– Mobile Virtual Network Operator (MVNO)– 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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CooperativeBusinessModels

• “Operators without networks”: MVNOs• “Operators without subscribers”: locally owned

access infrastructure– Overlay service provider (e.g., PBMS)– Organizational service provider (e.g., UCB IS&T)– Billing consolidation: single bill for service

• Device ensembles: virtual devices– Cooperation among access network providers, e.g.,

cellular/data + WLAN for hotspots/high rate data

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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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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

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Summary and Conclusions

• Observations:– Support for multiple service providers had to be

retrofitted to original Internet architecture– Telephony architecture better developed model of

multiple service providers & peering, but with longer-lived agreements, fewer providers

– Need for support in a more dynamic environment, with larger numbers of service providers and/or service instances

• Key Approaches:– Service Composition– Topology-awareness– Brokering vs. Confederation– Market-based Mechanisms for Resource Allocation

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Project Mascot: Camilla

Barker-Poles