Transcript Pervasive2002 - BNRG - University of California, Berkeley

Pervasive 2002
Zurich Switzerland
Pervasive Computing:
It’s All About Network Services
Randy H. Katz
The United Microelectronics Corporation Distinguished Professor
Computer Science Division, EECS Department
University of California, Berkeley
Berkeley, CA 94720-1776 USA
[email protected]
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New Pervasive Networking
Opportunity
• New things you can do inside the network
• Connecting end-points to “services” with processing
embedded in the network fabric
• Not protocols but “agents” well-specified behavior,
executing in places in the network
• Layer violation to enhance awareness acceptable:
location, network topology, data format, protocol,
subscriber identify, service in execution
• Scalable session and flow-oriented processing:
measuring, monitoring, billing, prioritizing
• No single technical architecture likely to dominate:
think overlays, system of systems
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Network Services: Communications
3
Network Services: Access
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New Kind of CommunicationsOriented Service Architecture
• Emerging, still developing, in a highly
heterogeneous environment
– Rapid development/deployment of new services & apps
– Delivered to radically diverse 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
– New business model emerging: tension between traditional
“managed” networks and services vs. “overlays” on top and
services outside
– Composition via cooperation or brokering to achieve enhanced
performance and reliability
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Presentation Outline
• Inevitability of Heterogeneity
• Service Composition via Cooperation, Brokering,
Peering, Overlays
• An Approach to a New Service Architecture
• A New Pervasive Networking Research Agenda
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Presentation Outline
• Inevitability of Heterogeneity
• Service Composition via Cooperation, Brokering,
Peering, Overlays
• An Approach to a New Service Architecture
• A New Research Agenda
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“X-Internet” Beyond the PC
Internet Computers
Internet Users
93
Million
Today’s Internet
407 Million
Automobiles
663 Million
Telephones
1.5 Billion
X-Internet
Electronic Chips
30 Billion
Forrester Research, May 2001
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“X-Internet” Beyond the PC
Millions
15000
10000
PC
Internet
5000
2010
2009
2007
2006
2005
2004
2003
2002
2001
0
2008
X
Internet
Year
Forrester Research, May 2001
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Shape of Things Now:
Ever More Sophisticated Phones
Siemens SL45i
Ericsson T68
• Phone w/voice command,
voice dialing, intelligent
text for short msgs
• MP3 player + headset,
digital voice recorder
• “Mobile Internet” with a
built-in WAP Browser
• Java-enabled, over the air
programmable
• Bluetooth + GPRS
• Enhanced displays +
embedded cameras
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Shape of Things Now:
New Converged Products
• Phone + Messenger + PDA Combinations
– E.g., Blackberry 5810 Wireless Phone/Handheld
» Integration of PDA + Telephone
» PLUS Gateway to Internet and Enterprise applications
» 1900 MHz GSM/GPRS (Euroversion at 900 Mhz)
» SMS Messaging, Internet access
» QWERTY Keyboard, 20 line display
» JAVA applications capable
» 8 MB flash + 1 MB SRAM
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Locator Systems =
GPS + 2-Way Messaging
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Shape of Things to Come:
Sensor Networks
• Embedded processing, time synchronization
mechanisms, real-time event handling, multihop
network routing, application development tools and
environments
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Environmental Sensing:
Sensor-to-Remote Researcher
• Great Duck Island
– Remote investigation of microhabitats
– David Culler, Alan Mainwaring, Intel Berkeley Laboratories
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Devices in the eXtreme
Information Appliances:
Many computers per person,
MEMs, CCDs, LCDs, connectivity
Information Appliances:
Scaled down desktops,
e.g., CarPC, PdaPC, etc.
Evolution
Revolution
Evolved Desktops
Servers:
Scaled-up Desktops,
Millennium
Mem
Smart Spaces
Display
BANG!
Mem
Keyboard
Disk
mProc
PC Evolution
mProc
Information
Utility
Disk
Camera
Server, Mem,
Disk
WAN
Camera
Display
Display
Smart
Sensors
Display
Servers: Integrated with
comms infrastructure;
Lots of computing in
small footprint
Computing
Revolution
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Pervasive Computing = “Convergence”
Via Services in the Network
• Not just about gadgets or access technologies,
which are becoming ever more diverse
• But services and applications, and how the net
can best support them anywhere, anytime
• Bottlenecks are near the edge, not the core
• Enabled by:
– Computing embedded in communications fabric:
distributed, wide-area, topology-aware
– Per session characterization, processing,
prioritization, monitoring, management, billing
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Presentation Outline
• Inevitability of Heterogeneity
• Service Composition via Cooperation, Brokering,
Peering, Overlays
• An Approach to a New Service Architecture
• A New Research Agenda
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Putting it Together: Connectivity
Cable
and Processing
Modem
Premisesbased
Access
Networks
Core Networks
WLAN
Transit Net
WLAN
Operatorbased
Cell
Cell
Cell
Regional
LAN
Transit Net
Premisesbased
WLAN
LAN
Internet
Datacenter
NAP
Public
Peering
Data
Voice
Analog
Transit Net
H.323
RAS
H.323
PSTN
LAN
Private
Peering
DSLAM
Data
Voice
Wireline
Regional
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Multi-Party Administered
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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“The Network Effect”
• Creating and deploying new services
– Development and deployment expense
» Cost of 3G licenses and networks
» “Even if I had $1 billion and set up 1000s of locations, I could
never in my network have a completely ubiquitous footprint.”—
Sky Dayton, founder of Boingo
• Achieving desirable end-to-end properties
– Control of the end-to-end path
• Evolving network services
– Difficult to change global operational infrastructure
• Approach: Peering, Composition, Overlays
– Needed: a service architecture that supports this
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Peering
Policy-Based Routing
• Multi-homing
– Reliability of network connectivity
– Traffic discrimination
Berkeley
Campus
End Network
Research
Traffic
CalREN
Peer
Peer
Peer
Network
Network
Networks
Network
Dorm
Traffic
Fail-over
Primary
Transit
Network
Alternative
New Primary
Transit
Transit
Network
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Composition
for GPRS Transit
Operator A
DNS
BG
BG
GGSN
GPRSPeering
PeeringNetwork
Network
GPRS
R
R
GRXR
R
R
DNS
Operator B
DNS
SGSN
DNSDNS
R
.gprs
R
BG
Operator C
R
R
GRX
GRX
DNS
R
GRX
DNS
R
DNS
SGSN
R
Operator C
BG
DNS
SGSN
• eXchanges
– Aicent, Belgacom, Cable & Wireless, Carrier1, Comfone/Infonet,
Deutsche Telekom, Ebone, Energis, France Telecom, Global Crossing,
KPNQwest, Sonera/Equant, Telecom Italia, Telenor, Telia,
Telecommunications Services Inc, WorldCom
Per Johannson, Ericsson Research
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Overlays
Creating New Interdomain Services
• Deploy new services above the routing layer
– E.g., interdomain multicast management and peering
– E.g., alternative connectivity for performance, resilience
Isolated
Intra-cloud
service
Administrative
domain
Admin
domain
Admin
domain
Administrative
domain
Admin
domain
Traditional
unicast
peering
Steve McCanne
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Overlays
Brokered Resources for Applications
• Examples:
– Multicast management and peering at application level
– Implement performance qualities at overlay level
Steve McCanne
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Composition and Cooperation:
Mobile Virtual Network Operator
MVNO has everything but its own physical network
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Composition of Wireless
Infrastructure Services
VPN Operator, Client-Software
WISP Aggregator
Private Brand Net
Operator (MVNO)
Single Sign-on
Unified Billing
Billing, ECommerce
Authentication
Inter-site Mobility
SLN Aggregator
Single Location
Network Operator
Single Location(SLN)
Network Operator
Single Location
(SLN)
Network Operator Cooperative
(SLN)
Networking
Revenue
Sharing
Full Service
Network
Full Service
Operator
Network
Full Service
Premises-based
Operator
Network
Operator
Access
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“Mobile Internet Edge”
Content optimization, policy-based filtering, security &
authentication, session/content/location/subscriber-aware
HW supports scaled monitoring/measurement for
allocation of resources, network management, charging, …
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Presentation Outline
• Inevitability of Heterogeneity
• Service Composition via Cooperation, Brokering,
Peering, Overlays
• An Approach to a New Service Architecture
• A New Research Agenda
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SAHARA Project
Service
Architecture for
Heterogeneous
Access
Resources and
Applications
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Scenario: Service
Composition
Restaurant
Guide Service
JAL
UI
Babblefish
Translator
NTTDoCoMo
Zagat Guide
User
Tokyo
Sprint
Salt Lake
City
User
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Service Composition
• 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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Service Composition Models
• Cooperative
– Individual component service providers interact, with distributed
responsibility, providing end-to-end composed service
Negotiation & control path
Service
Service
Service
Data flow
• Brokered
– Broker uses functionalities provided by underlying service
providers, encapsulates these to compose an end-to-end service
Negotiation & control path
Broker
Service
Data flow
Service
Service
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Layered Reference Model for
Service Composition
Middleware Services
End-to-End Network
With Desirable Properties
Enhanced Paths
Enhanced Links
Connectivity
Plane
Service
Composition
Applications Services
Application
Plane
End-User Applications
IP Network
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Technical Themes
• Trust management and behavior verification
– Meet promised functionality, performance, availability
• Adapting to network dynamics
– Actively respond to shifting server-side workloads and network congestion,
based on pervasive monitoring & measurement
– Awareness of network topology to drive service selection
• Adapting to user dynamics
– Resource allocation responsive to client-side workload variations
• Resource provisioning and management
– Service allocation and service placement
• Interoperability across multiple service providers
– Interworking across similar services deployed by different providers
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Presentation Outline
• Inevitability of Heterogeneity
• Service Composition via Cooperation, Brokering,
Peering, Overlays
• An Approach to a New Service Architecture
• A New Research Agenda
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Overlays to Deploy Disruptive
Services in Existing Networks
• How can overlays be exploited for greater network
resilience and performance?
– Faults be better isolated and diagnosed?
– Abstractions of topology and performance?
• Placement, Paths, and Load Balancing
– 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
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Placement of Intelligence in
the Network
• Is the end-to-end model still the right
conceptual framework?
• Composition via Brokering and Cooperation
– Separation of Service, Server, Service Path
– Assume “Server Centers” known, can be “discovered” 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?
• Service Appliances at the MIE
– How to exploit per-user session characterization and
pervasive measurement and monitoring?
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Pervasive Computing = Pervasive
Communications and Processing
• Increasing diversity of interconnected devices
• Increasing importance of “services” to
mitigate diversity and to provide new
functionality and customization
• Enabled by processing embedded in the
network interconnect, locally and globally
– “Active networking” is real
• Global services realized through managed
composition
– Recognition of the role of multiple service providers and
administrative domains
– Separation of services from connectivity via overlays
– No single operator deploys the global service
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Pervasive
2002
Pervasive
Computing:
It’s All About
Network Services
Randy H. Katz
Questions
Please!
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