at&t cambridge laboratory 10 september 1999 iceberg.cs.berkeley

1

Beyond Third Generation Cellular

Networks:The Integration of

Internet and Telephony Technology

Prof. Randy H. KatzUC Berkeley

AT&T Cambridge Laboratory10 September 1999

http://iceberg.cs.berkeley.edu Cellular “Core” Network

Bridge to theFuture

S. S. 7

2

Outline

• Motivation• It’s all about Services• The ICEBERG Project• Summary and Conclusions• New Project: Endeavour Expedition

3

Outline


4

Mobile Telephone & Internet Users

0

100

200

300

400

500

600

700

1993 1994 1995 1996 1997 1998 1999 2000 2001

Source: Ericsson Radio Systems, Inc.

Mobile TelephoneUsers

Internet Users

Millions

Year

5

Shift Toward Digital Mobile Access Network

0

100

200

300

400

500

600

700

1993 1994 1995 1996 1997 1998 1999 2000 2001

Millions ofSubscribers

Year

Digital

Analog

Source: Ericsson Radio Systems, Inc.

Providesa ubiquitous

infrastructurefor wirelessdata as well

as voice

6

Data Dominates

02468

10121416

VoiceIP

United States Network Traffic Growth (gigabits, bn)

Source: Nortel in The Economist, 13 Mar 99

7

Internet Telephony

Local Call Local CallInternet

Analog Voice toPacket Data

Packet Data toAnalog Voice

Gateway Gateway • High Latencies/Dropped Packets being solved• Short term: circuit-switched local infrastructure plus

packet-switched wide-area infrastructure• Longer term: migration towards “always on” digital

broadband data connections

8

Core Network BecomesData-Oriented

IP-Based WAN

Local Exch Local ExchPSTN

Local SwitchIWF + Router

Local SwitchIWF + Router

Voice TrafficConnection-Oriented

Data TrafficPacket-Oriented

Local Gateway Local GatewayCore NetworkAccessNetwork

AccessNetwork

Local ExchNet (LEC)

Local ExchNet (LEC)

InterexchangeNetwork (IXC)

Local Switch Local Switch

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IP-Based WAN

Packet-OrientedVoIP Gateway VoIP Gateway

Core NetworkAccessNetwork

AccessNetwork

Router Router

Core Network BecomesData-Oriented

• Routing infrastructure with support for differentiated services

• Open question: service-level agreements that span multiple ISPs

10

Smart Appliances/Thin Clients

Qualcomm PDQ Phone

PDA

PCS

11

• Top Gun MediaBoard– Participates as a reliable

multicast client via proxy in wireline network

• Top Gun Wingman– “Thin” presentation layer in PDA

with full rendering engine in wireline proxy

12

Important Trends Revisted

• Multimedia / Voice over IP networks– Lower cost, more flexible packet-switching core network– Simultaneous support for delay sensitive and delay insensitive

flows via differentiated services• Intelligence shifts to the network edges

– Third-party functionality downloaded into Information Appliances like PalmPilots

• Programmable intelligence inside the network– Proxy servers intermixed with switching infrastructure– Mobile/extensible code, e.g., JAVA: “write once, run anywhere”– Rapid new service development– Speech-based services

13

Outline


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The Future: Internet-basedOpen Services Architecture

“Today, the telecommunications sector is beginning to reshape itself, from a vertically to a horizontally structured industry. … [I]t used to be that new capabilities were driven primarily by the carriers. Now, they are beginning to be driven by the users. … There’s a universe of people out there who have a much better idea than we do of what key applications are, so why not give those folks the opportunity to realize them. … The smarts have to be buried in the ‘middleware’ of the network, but that is going to change as more-capable user equipment is distributed throughout the network. When it does, the economics of this industry may also change.”

George Heilmeier, Chairman Emeritus, Bellcore

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Policy-basedLocation-basedActivity-based

Speech-to-TextSpeech-to-Voice Attached-EmailCall-to-Pager/Email Notification

Email-to-SpeechAll compositions

of the above!

Universal In-box

Transparent Information Access

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RoomEntity

Text toCommand

ICSISpeech

RecognizerMicrophoneCell phone

A/V Devices

Response to Client

PathAudio Text Cmd

Composable Services• E.g., voice control of A/V devices in a “Smart Room”

– Multistage processing transformation– Strongly typed connectors– Service discovery service– Automated path generation

17

Outline


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ICEBERG: Internet-based CorE BEyond the thRid

Generation• The Challenge

– Developing service intensive, network-based, real-time applications – Securely embedding computational resources in the switching fabric– Providing an open, extensible network environment: heterogeneity

• Computing– Encapsulating legacy servers & partitioning “thin” client functionality– Scalability: 100,000s of simultaneous users in the SF Bay Area

• High BW IP backbones + diverse access networks– Different coverage, bandwidth, latency, and cost characteristics– Third generation cellular systems: UMTS/IMT2000– Next gen WLANs (Bluetooth) & broadband access nets (DSL/cable)

• Diverse appliances beyond the handset or PC– Communicator devices plus servers in the infrastructure

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Project Goals• Demonstrate ease of new service deployment

– Packet voice for computer-telephony integration– Speech- and location-enabled applications– Complete interoperation of speech, text, fax/image across the

four P’s: PDAs, pads, pagers, phones)– Mobility and generalized routing redirection

• Demonstrate new system architecture to support innovative applications

– Personal Information Management» Universal In-box: e-mail, news, fax, voice mail» Notification redirection: e.g., e-mail, pager

– Home networking and control of “smart” spaces, sensor/actuator integration

» Build on experience with A/V equipped rooms in Soda Hall

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Experimental Testbed

SimMillenniumNetwork

Infrastructure

GSM BTS

Millennium Cluster

Millennium Cluster

WLAN /Bluetooth

Pager

IBMWorkPad

CF788

MC-16

MotorolaPagewriter 2000

306 Soda326 Soda “Colab”

405 Soda

Velo

Smart SpacesPersonal Information Management

TCI @Home

H.323GW

Nino

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Computing and Communications Platform: Millennium/NOW

Distributed Computing Services: NINJA

Active Services Architecture

MASH Media Processing Services

DistributedVideoconferencing

& Room-scaleCollaboration

TranSend ExtensibleProxy Services

ICEBERGComputer-Telephony Services

Speech and LocationAware Applications

Internet-Scale Systems Research Group

ICEBERGComputer-Telephony Services

Speech and LocationAware Applications

Personal Information Management and “Smart Spaces”

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• Bases (1M’s)– scalable, highly available– persistent state (safe)– databases, agents– “home” base per user– service programmingenvironment

Wide-Area Path

• Active Proxies (100M’s)– not packet routers, may be AN nodes – bootstrap thin devices into infrastructure– soft-state and well-connected

NINJA Distributed Computing Platform

• Units (1B’s)– sensors / actuators– PDAs / smartphones / PCs– heterogeneous– Minimal functionality:

“Smart Clients”

Jinidevices

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ICEBERG Principles ...

• Potentially Any Network Services (PANS)– Any service can from any network by any device;

network/device independence in system design• Personal Mobility

– Person as communication endpoint with single identity• Service Mobility

– Retain services across networks • Easy Service Creation and Customization

– Allow callee control & filtering• Scalability, Availability, Fault Tolerance• Security, Authentication, Privacy

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ICEBERG Architectural Elements

• ICEBERG Access Point (IAP)– Encapsulates network specific gateway (control and data)

• ICEBERG Point of Presence (iPOP) – Performs detailed signaling

» Call Agent: per communication device per call party» Call Agent Dispatcher: deploy call agent

• Name Mapping Service– Mapping between iUID (Iceberg Unique ID) and service end point

• Preference Registry– Contains user profile:service subscription, configuration. customization

• Person Activity Tracker (PAT)– Tracks dynamic information about user of interest

• Automatic Path Creation Service– Creates datapath among participants’ communications devices

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Transformation and Redirection

IP Core

PSTN

Pager

WLANCellularNetwork

H.323GW

GW

GW

GW

IAP

IAP

IAP

IAPIAPTransducerAgent

RedirectionAgent

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ICEBERG Signaling System

• Signaling System– Distributed system w/agents communicating via signaling

protocol for call setup, routing, & control• ICEBERG Basic Call Service

– Communication of two or more call participants using any number of communication devices via any kind of media

– If call participant uses more than one devices, must be used synchronously

• Basic Approach– Loosely coupled, soft state-based signaling protocol

w/group communication– Call Session: a collection of call agents that communicate

with each other

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Signaling: Call Session Establishment

Name MappingService

Preference Registry

Alice Bob

Carol

IAP1

33 5

6

IAP78 9

1011

1314IAP 15

16

2Call Agent Dispatcher

Call Agent

iPOP


Call Agent

iPOP


Call Agent

iPOP

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Signaling: Call Control

• Call Control– Refers to control protocol in an established call session– Involves altering & propagating call states in the call session,

and modifying the datapath correspondingly• Call States

– Call party identities, communication devices in use & their call status, and datapath information on data streams involved

• Challenge– Reliable propagation of call state changes to call agents,

given highly dynamic call session environment» Adapt as session membership changes» New member must be able obtain current session state

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ICEBERG Approach for Call Control

• Call Session – Abstraction of shared communication channel– Level of indirection to hide identity and location of call

session members (I.e., call agents)– Adapt to membership change

• Call State– Soft state-based– Maintained by each call agent in a session

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Light-Weight Call Session

Call Agent

Call AgentData Path

Table

Call Session

Auto PathCreation

Call State Table

Call Agent

Announce Announce

Listen Listen

Create/tear downdata path

Create/tear downdata path

Add orremove

path

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Datapath Simplification

• Separate data from control– Isolate datapath creation from signaling– Encapsulates media negotiation

• Powerful enabler for any-to-any communication in ICEBERG due to its flexible composability

• Current use immature and ad-hoc– Operator with reference count– Operator description: what and where to run or

cleanup– Who gets to create path

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Signaling: Fault Detection and Recovery

• Ninja Distributed Service Environment– Run all Iceberg components on Ninja Base

• Advantageous separation of iPOP and IAP– IAP: network specific gateways likely maintain hard

state;Gateways are responsible for maintenance

– iPOP: light-weight call session is the key• Detection

– IAP and iPOP send heartbeats to each other– Loss of heartbeat implies loss of life

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Conference Call: First Class Service

• Redefining conference call – Call between at least two call parties with at least

three communication devices• Conference call operations are building

blocks for services– Add a communication endpoint– Remove a communication endpoint

• Simplify implementation of services that require communication endpoint changes

– Change an endpoint = remove + add

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Example: Service Handoff

• Service handoff occurs when users switch communication devices in midst of call session

• Enables service mobility• Service handoff is:

– Generalized call transfer– Special case of conference call

» User uses one device to invite another device» Then hangs up the first device

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Service Handoff Scenario:Cell Phone to Laptop

CallerIAP

CalleeIAP

CallerIAP2

handoff fromcell phone to

VAT

Multicast Session

announceListen

announceListen

announceListen

Cell phoneturned off

Start new IAP

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Service Handoff Scenario

CallerIAP

CalleeIAP

CallerIAP2

handoff fromcell phone to

VAT

Multicast Session

announceListen

announceListen

Cell phoneturned off

Start new IAP

• Simple reliability scheme• IAP fault tolerant• Simultaneous service handoff• Multiparty calls trivial• Security through encryption

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Comparison with SIP, H.323

• SIP Differences – Group vs. pairwise

communication for signaling– Light-weight session vs. tightly

coupled session• Our Advantages

– Adaptive to dynamic call session (i.e., call session membership change, protocol agent fault recovery)

– Simplicity in service implementation

• H.323 Problems– Complexity: no clean

separation of component protocols; many options for doing a single task

– Extensibility: requires full backward compatibility; each codec is centrally registered and standardized; not modular

– Scalability: stateful (depends on TCP); central control for conference call

– Services: cannot express preferences

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Implementation and Current Status

• Prototype system built on Ninja iSpace using Java (~5000 line code)

• Thread programming model rather than event-driven -- implicit state machine

• Conference call service operational• Service handoff now being implemented

(between PSTN, GSM, WaveLAN)• LDAP for the Name Mapping Service• Preference Registry: forms-based

specification yielding Perl scripts

39

Outline


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Summary

BasesActiveProxies

UnitsNinja ExecutionEnvironment

Data PlaneOperators Connectors

Paths

ControlPlane

IAP

PAT

PRLS

APC

Pref Reg

Name S

vc

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Conclusions• Emerging Network-centric Distributed Architecture

spanning processing and access• Open, composable services architecture--the wide-

area “operating system” of the 21st Century• Beyond the desktop PC: information appliances

supported by infrastructure services--multicast real-time media plus proxies for any-to-any format translation and delivery to diverse devices

• Common network core: optimized for data, based on IP, enabling packetized voice, supporting user, terminal, and service mobility

42

Outline


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Why “Endeavour”?

• DARPA BAA 99-07: Information Technology Expeditions

• To strive or reach; a serious determined effort (Webster’s 7th New Collegiate Dictionary); British spelling

• Captain Cook’s ship from his first voyage of exploration of the great unknown of his day: the southern Pacific Ocean (1768-1771).

– These voyages brought brought more land and wealth to the British Empire than any military campaign

– Cook’s lasting contribution: comprehensive knowledge of the people, customs, and ideas that lay across the sea

– “He left nothing to his successors other than to marvel at the completeness of his work”

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Expedition Goals

• Enhancing human understanding through information technology

– Dramatically more convenient for people to interact with information, devices, and other people

– Supported by a “planetary-scale” Information Utility» Stress tested by challenging applications in decision making

and learning» New methodologies for design, construction, and

administration of systems of unprecedented scale and complexity

– Figure of merit: how effectively we amplify and leverage human intellect

• A pervasive Information Utility, based on “fluid systems technology” to enable new approaches for problem solving & learning

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Expedition Assumptions

• Human time and attention, not processing or storage, are the limiting factors

• Givens:– Vast diversity of computing devices (PDAs, cameras,

displays, sensors, actuators, mobile robots, vehicles); No such thing as an “average” device

– Unlimited storage: everything that can be captured, digitized, and stored, will be

– Every computing device is connected in proportion to its capacity

– Devices are predominately compatible rather than incompatible (plug-and-play enabled by on-the-fly translation/adaptation)

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Expedition Challenges

• Personal Information Mgmt is the Killer App– Not corporate processing but management, analysis,

aggregation, dissemination, filtering for the individual• People Create Knowledge, not Data

– Not management/retrieval of explicitly entered information, but automated extraction and organization of daily activities

• Information Technology as a Utility– Continuous service delivery, on a planetary-scale, on

top of a highly dynamic information base• Beyond the Desktop

– Community computing: infer relationships among information, delegate control, establish authority

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Interdisciplinary, Technology-Centered

Expedition Team• Alex Aiken, PL• Eric Brewer, OS• John Canny, AI• David Culler, OS/Arch• Joseph Hellerstein, DB• Michael Jordan, Learning• Anthony Joseph, OS• Randy Katz, Nets• John Kubiatowicz, Arch• James Landay, UI

• Jitendra Malik, Vision• George Necula, PL• Christos Papadimitriou, Theory• David Patterson, Arch• Kris Pister, Mems• Larry Rowe, MM• Alberto Sangiovanni-

Vincentelli, CAD• Doug Tygar, Security• Robert Wilensky, DL/AI

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Expedition Approach• Information Devices

– Beyond desktop computers to MEMS-sensors/actuators with capture/display to yield enhanced activity spaces

• InformationUtility

• InformationApplications

– High Speed/Collaborative Decision Making and Learning

– Augmented “Smart” Spaces: Rooms and Vehicles

• Design Methodology– User-centric Design with

HW/SW Co-design;– Formal methods for safe and trustworthy

decomposable and reusable components

“Fluid”, Network-Centric System Software

– Partitioning and management of state between soft and persistent state

– Data processing placement and movement

– Component discovery and negotiation

– Flexible capture, self-organization, and re-use of information

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InformationUtility

InformationDevices

ApplicationsCollaboration SpacesHigh Speed

Decision MakingLearning

ClassroomInfo AppliancesE-Book Vehicles

PDAHandset

Laptop CameraSmartboard MEMS Sensor/Actuator/Locator

Wallmount Display

Generalized UI Support

Proxy Agents

Human Activity CaptureEvent Modeling Transcoding, Filtering, AggregatingStatistical Processing/InferenceNegotiated APIs Self-Organizing DataInterface Contracts Wide-area Search & Index

Nomadic Data & ProcessingAutomated Duplication

Distributed Cache ManagementWide-Area Data & ProcessingMovement & Positioning

Stream- and Path-Oriented Processing & Data MgmtNon-Blocking RMI Soft-/Hard-State Partitioning

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Organization: The

Expedition Cube

Information Devices

Information Utility

ApplicationsDesIgn

Methodology

MEMS Sensors/Actuators, Smart Dust, Radio Tags, Cameras, Displays, Communicators, PDAs

Fluid Software, Cooperating Components,Diverse Device Support, Sensor-CentricData Mgmt, Always Available, TacitInformation Exploitation (event modeling)

Rapid Decision Making, Learning,Smart Spaces: Collaboration Rooms,Classrooms, Vehicles

Base ProgramOption 1: Sys Arch for Diverse DevicesOption 2: Oceanic Data Utility

Option 4: Negotiation Arch for CooperationOption 5: Tacit Knowledge InfrastructureOption 6: Classroom TestbedOption 7: Scalable Heterogeneous Component-Based Design

Option 3: Capture and Re-Use

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Putting It All Together1. Diverse Devices2. Data Utility3. Capture/Reuse4. Negotiation5. Tacit

Knowledge6. Classroom7. Design Methods8. Scale-up

Devices

Utility

Applications

Fluid Software

Info Extract/Re-use

Group Decision MakingLearning

Component Discovery& Negotiation

Self-Organization

at&t cambridge laboratory 10 september 1999 iceberg.cs.berkeley

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