ProActive Infrastructure

Eric Brewer, David Culler,

Anthony Joseph, Randy Katz

Computer Science Division

U.C. Berkeley

ninja.cs.berkeley.edu

Active Networks Workshop, July 1998

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Vision --> Goal

• The next internet revolution will come from enabling component services and pervasive access.

=> Enable programatic creation and composition of scalable, highly available, customizable services that adapt automatically to the characteristics of the end devices (clients, sensors, and actuators) and their connectivity through the network.

• Arbitrarily powerful services on arbitrarily small clients through integration with a powerful, proactive infastructure

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Imagine

• You walk into a room,

• your Palm Pilot V discovers the devices there and builds a user interface for them;

• it discovers the path out into the infrastructure to your personal information space which is searching, filtering, and transcoding on your behalf

• and you have complete, secure, optimized access from a spectrum of devices available to you.

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Starting Point: Transcoding Proxies

Stationarydesktops

Information appliances

ScalableServers

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Basic Approach

• Create a framework that enables programatic generation and composition of services out of strongly typed reusable components

• Key Elements– structured architecture with a careful partitioning of state

» Bases, Active Routers, and Units

– wide-area paths formed out of strongly-typed components

» Operators and Connectors

– execution environments with efficient, but powerful communication primitives

» Active Messages + capsules

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Structured Architecture

• Bases– highly available– persistent state– databases, computing– agents– “home” base per user

• Active Routers– soft-state– well-connected– localization

• Units– sensors/actuators– PDAs/Smartphones– Laptops, PCs, NCs– heterogenous

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Behavior

• Units find ARs

• Build a “wide area path” of connectors and operators to service.

• Active transformation at each step

• Careful management of state

Units

Activerouters

Bases

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Architecture Benefits

• Mobility– any AR + home base

• State– soft-state at Ars, persistent at Bases

• Scalability, Availability– Units use Smart Clients approach at AR

– Bases provide service programming environment

» TACC + persistence + customization

• Enables extremely simple clients

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Wide-Area Paths

• Path is first-class entity

• Explicit or automatic creation

• Can change dynamically– change path or operators

• Unit of authentication -- delegate along the path

• Unit of resource allocation

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Operators/Connectors

Operators:– transformation– aggregation– agents

Connectors:– abstract wires

– ADUs

– varying semantics

– uni/multicastInterfaces:

– strongly typed

– language independent

– control channel» path changes» authentication» feedback

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Path Formation, Optimization, Interoperability

• Service discovery query finds logical path of operators

• Place operators onto nodes

• Connectors are polymorphic– entire path must type check - statically

• Add (or transpose) operators – forward error-correction

– compression/decompression

• Change parameters, reroute

• Wrapper operators of legacy servers

• Leverage COM objects as operators

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TopGun Wingman/Mediaboard

• Eric’s slide is in PDF

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Campus-wide Testbed (Millennium)

Gigabit Ethernet

PDAs Cell PhonesFuture Devices

WirelessInfrastructure

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Milestones

• Year 1– Architecture Definition, Operator/Connector Type System,

Active Message-based Active Net

– Technology: PIM proto. With COTS database, Auto connection, NOW Base, Test Units

• Year 2– WAP with intermittent connectivity, execution environment for

Base, AR, Unit

– Technology: COM integration, shared link mgmt, multicast connectors, Type hierarchy

– Working testbed, PIM prototype

• Year 3– WAP transformation, operator migration, large-scale agents

– FSM-based fast operators, operator fusion, migration

– Full testbed, smart-space, PIM release