Pervasive Services Infrastructure Dejan S. Milojicic HP Labs, Palo Alto 315 2001 http:www.hpl.hp.com

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Pervasive Services Infrastructure (?)Dejan S.
MilojicicHP Labs, Palo Alto3/15
2001http//www.hpl.hp.com/research/itc/csl/pss/ps
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?s Strategic Direction

• Global eCommerce to reach 6.8 trillion by 2004
  (Forrester Research)
• Internet Service Gateway market to reach 25M US
  homes by 2005, worth 5B (Parks Assoc.)
• Commerce over mobile phones in W. Europe rise to
  37.7B in 2004 (51.2M in 1999, IDC)
• Worldwide shipments of handheld computers will
  surpass 5.7M, 47 increase (Dataquest)

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What is Disruptive in this Space

• General
• pervasive (ubiquitous, invisible) deployment of
  computers, smart spaces
• scale large number of devices (localized)
  services
• User perspective
• user interfaces, user intent
• context awareness
• diversity of services and clients
• connectivity
• Developer perspective
• versioning and maintaining products (scale
  thereof)
• variation in network speed (wireless ? wired
  wired ? memory)
• the price of each component (reduced cost)
• service interoperability (everything available on
  the Internet)

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Tough Problems Today

• Wireless speed (need higher bandwidth, lower
  latency)
• Unreliable connections (missing disconnected
  support)
• Lack of apps and app development tools
• Lack of solid infrastructure (database,
  synchronization)
• Non-scalable solutions
• Non-trusted solutions (lack of end-to-end
  security)
• Lack of quality displays U/I
• Few users (innovators and early adopters)
• Protocols evolving (WAP, XML implementations,
  APIs)
• User experience (clumsy handheld, poor I/F)
• Viability (fractured embedded OS space)

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Relaxing Assumptions for 2004(not all problems
are Y s)

• Ubiquitous connectivity (3G)
• End-to-end security (Wireless VPN)
• Device interoperability (Lucent Novell,
  Motorola Lucent, etc)
• Better battery lifetimes (piezoelectric, solar,
  bioelectric, etc.)
• Handheld, phones, others, converged
• Billing, customer care ? commodity services
• Voice U/I (many already work on)
• Higher quality color displays
• New Web apps built from ground up
• Middleware solutions adapt access to existing
  apps
• Wireless Web crosses the chasm
• Consolidation of embedded OS space

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What are Remaining Problems

• Scalability (localized)
• Service access and adaptivity in dynamic
  environments
• Administration (automatic, transparent,
  dependency aware)
• One-size fits all (embedded system software
  solutions)
• Interoperability (APIs, service brokers, etc.)
• Performance e.g. load, latency, caching
• Maintaining true end-to-end security guarantees

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Scenario

• Scene Helsinki airport, year 2004. Jane and
  Dave are on a business trip to present a new
  product to overseas customers. Dave worked the
  whole weekend at home on an updated presentation.
  They are stepping off of the plane.
• Jane Relax Dave, everything is going to be fine.
  Your presentation is in good shape. Just fix the
  typo in the CTOs name and tune the figures,
• Dave Fix the title! Tune the figures! Are you
  out of your mind?! I only have the presentation
  on my phone. Id need to download and fix it on
  my laptop. We dont have time for that before the
  meeting.
• Jane Yes, you can. I can do it on my new phonDA.
• Dave You never told me you got a new, more
  powerful phonDA
• Jane No, its the same as yours, NK234yP, but
  Ive updated the software.
• Dave No way, my presentation is 4G. It cant
  fit on any phonDA
• Jane Look, I download your presentation ...
  Heres the slide you want, ok the CTOs title
  is fixed, now lets see the figures itll take
  longer ok, here are figures, move the 2003
  forecast up a little, .. perfect.

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Scenario, cont.

• Dave How did you do it?!! Look, Im downloading
  it on my phonDA and it takes forever even worse,
  now it wont start.
• Jane You see those small bumps on the walls,
  ceiling, and floor. These are embedded servers.
  Software on my phonDA offloads networking,
  memory, processing, storage - you name it - to
  these servers.
• Dave Sigh
• Jane It is called Psi its very simple. Now
  with respect to these bumps on walls, hold on a
  second my daughter is paging me, first things
  first. Yes honey, I forgot to sign your
  homework ooops
• Dave Can your magic Psi help with this too?
• Jane Sure it can, see, here it will download her
  application from her school it adapts to my
  phonDA since the app is designed for desktops
  its really downloaded on a server there. Looks
  correct, ok signed!

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Scenario, cont.

• Dave Wow, you are a wizard, installing all these
  applications, adapting them to your small phonDA.
  How long did it take you?
• Jane Not a second, Psi does it all, it adapts,
  it downloads services on demand.

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Pervasive Servers Clients
..servers
IDCs
..intermediate servers
infrastructure
?
..clients
embedded
..embedded devices and sensors
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Conceptual Layers
Services and Applications
? platform match service requirements to client
resources
Local OSes JVMs
Client Handheld Device (and Infrastructure
Servers)
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? Vision

• Adapt any service to any client (anywhere,
  anytime)
• General assumptions
• clients will always be diverse
• clients will always be less powerful than
  desktops
• there will be a large scale of devices in the
  future
• services will be accessible on demand from
  anywhere
• Underlying Y assumptions
• service adaptivity required
• three-tier model
• service splitting

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?, Important Research Questions

• How to enable users to exploit the new pervasive
  computer infrastructure
• How to seamlessly offer more services to more
  clients anytime anywhere?
• How to avoid installing and administering
  increasing number of computers in a pervasive
  infrastructure?
• What are new abstractions and algorithms for
  computation, communication, storage, user
  interface ? how to write and run new apps?
• It is not the strongest of the species that
  survive, nor the most intelligent, but the ones
  most responsive to change - Charles Darwin

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Adaptive Offloaded Services

• Goal increase scalability performance of
  (mobile) service deliveryto resource-poor
  devices and enable where not currently possible
• Key research questions
• Splitting service between client and mid-point
  (intermediate) servers
• Dynamic adjustment of services device size,
  load, roaming
• Masking performance implications of splitting
• Required infrastructure topics
• Distributed run-time support - mid-point(s) and
  client
• Sharing, administration, and security at
  mid-points

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Adaptive Offloaded Services Illustration
1110
0101
DSL
1110
0101
Phone
1110
0101
Embedded server dependent execution
1110
0101
Which?
Back-end service execution
Home, office, shop, etc.
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Adaptive Offloaded Services, Cont.

• Splitting services
• Monitoring (resources, execution, objects)
• Offloading (migration mechanisms, trigger
  placement policies)
• Service splitting (interaction metrics, graph
  partitioning, 3-v. 2-tier)
• Adaptive Offloading
• Adapting to devices (very constrained, different
  resources)
• Adapting to load (multiple services, scalability)
• Adapting to mobility (roaming, migration of
  offloaded state)
• Performance
• Policies (account for overhead, interaction
  metric, stability)
• Mechanisms (offloading overhead, disruption of
  offloading - lazy)

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The Java Heap Page Working Set of Embedded
Caffeine Mark
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Services on Demand

• Goal zero-administration and -installation of
  mobile clients
• Key research questions
• dynamic service composition and deployment on
  zero-installed devices
• de/re-coupling of users service context between
  devices
• tolerance to disconnection of services
• Required infrastructure topics
• service brokers and infrastructure
• device encapsulation APIs

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Services on Demand Illustration
Day 1, John in Sydney
User data/profile/registry
Service Lookup
Service download
Day 2, John in Montreal
Back-end service execution
Home, office, shop, etc.
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Loading Overheads
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Services on Demand, Cont.

• Service Composition/Deployment on Zero-Installed
  Devices
• service characterization (naming, keyword,
  extension, requirements)
• service discovery (brokers, resource matching,
  scalability)
• deployment (transparent downloading caching,
  sandboxing for service inter-communication
• De/re-Coupling of Service Context Between Devices
• remote storage (clients are volatile, access any
  time anywhere, user/service transparency,
  stackable client RFS, synchronization/encryption)
• context information (per service state,
  preferences, expressed as files)
• Adaptation to different client (resource
  re-evaluation, select service)
• Tolerance to Disconnection of Services
• client side cache (static content URLs, classes
  user files/data user/service network
  interactions
• reconnection (pluggable reconciliation per
  service/file, client-initiated

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Architectural Principles

• Minimal changes (extensions) to the underlying
  client sys SW
• Minimal changes to services (mainly splitting)
• Use existing mid-point servers in the
  infrastructure
• Psi will rely on standard communication protocols
  (IP, WAP, etc)however, it will have the ability
  to support extension to new ones
• Heterogeneity of underlying OSes and
  implementation of JVMs
• The primary metric will be enabling new services
  and better use of resource-constrained devices

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Implementation Details

• Prototype environment
• Jornada Pocket PC
• Java VM, Chai VM
• wireless 802.11
• Linux PCs for infrastructure servers
• Services
• tools editors (text/image)
• visualization
• PIM calendars, mail, calculators, stock analysis
• interactive games
• etc.

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Technical Approach

• Develop a Y architecture prototype
  implementation
• Experimental, quick prototyping, 3-month
  increments
• Spiral approach
• Incrementally demonstrate new functionality
• Uncover new key questions
• Engage partners at incremental 3-month phases
• HPL, HP, university, industry (external)
• Patent/publish as we progress

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Showcases

• Adaptive offloaded servicesinitial mobile app
  splitting, evaluate split advantage
  (scale/perf/power)
• app which is too resource intensive for existing
  devices
• app which is interactive ? mobile editing and
  interactive gaming
• app which is data intensive ? mobile multimedia
  and visualization
• Service-on-Demand service broker lookup,
  automatic download, disconnected mode
  (cache/remote)
• app that can work disconnected (runs part of the
  service locally)
• app that accesses user data from a server
• app in two different flavors, to adapt to Palm
  constrained resources

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Current Insights

• Opportunity for memory offloading
• Complex interactions in Java objects
• Transparent remote storage class interposition,
  bytecode editing
• Disconnection caching of some class
  client/service interactions
• Reconciliation through plugins

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Team Members

• Resource-Constrained Devices, team leadOS, JVM,
  consumer products (Sony)
• Team memberHA, distributed systems (SRI,
  Informix, Oracle)
• Services-on-Demand, team leadOS, JVM (Bull, OSF
  RI)
• Dejan Milojicic, (myself) Psi PMOS, distributed
  systems agents (Belgrade RI, OSF RI)

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Competition

• Telcos
• ATT, Motorola, Ericsson
• Consumer electronics companies
• Sony, Philips, etc. (HAVI)
• Traditional computer systems companies
• Sun (Jini, embedded/real-time Java) Microsoft
  (.NET, Windows CE)IBM (pervasive computing,
  embedded tools)
• Data base companies
• Oracle, Sybase
• Many startups
• StreamTheory, OmniShift, Transvirtual,
  M2Verticom, WirelessKnowledgeMany universities,
  government
• Numerous competition, but huge business
  innovation opportunity

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Related Work

• Adaptability Offloading
• UW (Portolano) Active Fabrics service
  infrastructure
• Berkeleys (Endeavor) Ninja general service
  offloading
• Palm, WinCE offloading to shared mid-points
• OSGi general purpose distributed UW Kimera
  dynamic service split
• CMU Odyssey, UIUC Active Spaces service
  splitting
• MIT Oxygen SW environment resource awareness
• Data storage resource management
• CMU Coda Odyssey reconciliation framework
• UCLA File mobility trust for services WebFS
  more than web browsing
• OSGI mobility Java OS JDI JPI API
  signatures
• Java platform
• JavaOS service infrastructure PocketLinux
  disconnected other OSes
• JNT, but not just a terminal WebOS service
  brokers trust

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What ? is Not About

• Client HW
• HW (re)configuration
• Service design implementation
• New protocols
• New programming languages
• General purpose wireless
• Device location technologies
• General purpose OS development
• Fault-tolerance
• Hard real-time

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Summary

• Intersection of services, the Internet, and
  wireless
• adapt services to existing client resources
• automate service deployment
• reason about new, disruptive technologies in
  pervasive computing
• Potential long-term area of research, ties in
• servers (IDCs) client pervasive infrastructures
• academia, government, big small companies
• different markets
• A lot of opportunities for contribution
  risk-aware, leverage potential
• It is fun to do these things! Immediate benefit
  obvious

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Pervasive Computing Landscape
information architecture XML UDDI VML
user studies
user/agent model (intelligence)
application model (information access
presentation)
security mgmt pricing/ charging development adapti
vity
nomadic
location transparency
task mobility
global data placement
context management
Y
internet com (IP)
mobile com. (non IP)
device connectivity
service connectivity
Y