Download Fully networked devices

Web Enabled Devices
&
home networks
Johan Lukkien
programme leader “home networks”
Eindhoven Embedded Systems Institute
Eindhoven University of Technology
Overview



Evolution of embedded systems and
embedded networking
Architecture of Web connected devices
Fully networked devices




requirements
a few example networks
Internet solutions
Conclusion
Johan Lukkien
11-4-2001
EESI Embedded Internet Colloquium 2
Embedded Systems
evolution

hardware replaces software





functionality
features
digitisation and manipulation of
signals
configuration/programming of
systems from outside
completely networked systems
Johan Lukkien
11-4-2001
EESI Embedded Internet Colloquium 3
Network aware:
Information
retrieval
Network
central: Adapt
product design with
from the system
rudimentary
fashion
respectintoathe
network connection
Network connected: On-line connection with
Fully
networked:
functionality
is defined
• Status
errors,the
wear,
use with embedded
• Integrate
network
functions
the information:
system
byhardware
the network
• Using existing
connections
and resources
and software
already
within the
•available
Standardisation
ofsystem
connections,
protocols
• Put
control hardware/software
next to
the
•analysis
Devicesofcontrolling
each other
• Off-line
data
embedded
system
• Intelligent
environments,
all equipment in the
• Transport:
telephone,
Internet
• Interaction!
Standalone:
embedded
network
central
network
aware(Philips: “ambient
background
intelligence”)
hardware and software:
time
• invisible
• are, in fact, an
standalone aspect network connected
fully networked
implementation
Advantage:http://aquarium.eesi.tue.nl
of Advantage:
the product
• remote ••diagnosis
service: access to embedded software:
debugging, replacement, sell features
Advantage:
• owner:
standardisation,
new
software
Advantage:
http://www.research.philips.com/generalinfo/special/ambintel/index.html
• service:
diagnostics,
leasing
of appliances
• service:
new
markets
• owner:
remote
monitor
& control, security,
• owner: ease
of fleet
use, maintenance
comfort,
integration
production-control,
Johan Lukkien
11-4-2001
EESI Embedded Internet Colloquium 4
Evolution of
embedded networking
The effect of Internet
• Data transport (large
distance)
• Standards: ftp, email, ...
network aware
• Distributed access
standalone
..... +
Interoperability
network
central
• Standards
for
time
offering services:
Jini, UPnP, OSGi
• Platform for
• Standards for
network connected• datafully
networked
exchange
• software architectures
integration
• communication: HTTP,•Java,
TCP, UDP, ....
• visualisation:
browsers
information
exchange!!
Johan Lukkien
• Global addressing
11-4-2001
EESI Embedded Internet Colloquium 5
Technical background

Moore: number of transistors/mm2 doubles
every 18 months


Metcalfe: de “value” of a network is
proportional to the square of the number of
nodes



processing power and memory capacity
become abundant
adding a node benefits existing nodes
the larger the network the larger the benefit
Gilder: Internet bandwidth triples every 18
months

bandwidth becomes abundant
Johan Lukkien
11-4-2001
EESI Embedded Internet Colloquium 6
Overview



Evolution of embedded systems and
embedded networking
Architecture of Web connected devices
Fully networked devices




requirements
a few example networks
Internet solutions
Conclusion
Johan Lukkien
11-4-2001
EESI Embedded Internet Colloquium 7
Architecture
Request connection
Remote user
Program code
sensors
Applet
HTML browser
Johan Lukkien
UDP
ES-Server
HTTP
(applet code)
11-4-2001
actuators
HTTP server
EESI Embedded Internet Colloquium 8
Components

HTTP server:

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

ES server: provide “driver interface” for
embedded system
HTTP browser (client):




standardized access: URL
code download: Java applet
setup contact
run machine-independent code
“programmable interactive remote control”
Applet:


interface to user
driver of ES
Johan Lukkien
11-4-2001
EESI Embedded Internet Colloquium 9
Trade-offs
Observer
Embedded
System
1
2
Actuators
&
Sensors
Connection 1: Internet
 protocol implicit: within applet
 protocol explicit:


available to other systems
protocol requirements:



access levels of users; security
state inspection and modification
notification of state changes
Johan Lukkien
11-4-2001
EESI Embedded Internet Colloquium 10
Trade-offs
Observer
Embedded
System
1
2
Actuators
&
Sensors
Connection 2:
 proprietary
 other network, e.g., i/o network, field bus
 Internet??


bus-like function for Internet
aggregation, embedded control
What are the criteria to put intelligence at an
actuator/sensor?
Johan Lukkien
11-4-2001
EESI Embedded Internet Colloquium 11
Example: ubicom room control
Devices not
networked
individually
http://www.ubicom.com
Johan Lukkien
11-4-2001
EESI Embedded Internet Colloquium 12
Example: EESI coffee maker
Switch and heat control
not networked
individually
Request connection
Program code
Remote user
Johan Lukkien
11-4-2001
EESI Embedded Internet Colloquium 13
Trade-offs
Observer
Embedded
System
1
2
Actuators
&
Sensors
Criterion supporting
intelligence at A&S
Connection
2:
• Hardware is locally necessary
 proprietary
• safety, real-time control (don’t distribute safety
 other
network,
e.g.,
i/o network,
field bus
issues
across an
unreliable
network)
• establishing relationship actuator-sensor
 Internet??
• process sensor input
bus-like function for Internet
 aggregation,
embedded control
Criteria
against intelligence

• Single
function
(ES is already
dedicated) at an
What
are
the criteria
to put intelligence
• Logical unit controlled from ES
actuator/sensor?
• No power available
Johan Lukkien
11-4-2001
EESI Embedded Internet Colloquium 14
Overview



Evolution of embedded systems and
embedded networking
Architecture of Web connected devices
Fully networked devices




requirements
a few example networks
Internet solutions
Conclusion
Johan Lukkien
11-4-2001
EESI Embedded Internet Colloquium 15
Fully networked devices


Separate user interface and driver functions
It must be simple to attach to the network



Zero configuration connection



lightweight
easy to handle
build a logical network automatically
peer to peer in absence of server
Zero configuration interoperable



service publication and discovery
devices control each other
no fixed identification
Johan Lukkien
11-4-2001
EESI Embedded Internet Colloquium 16



(Sunbeam)
powerline, RF
Zero-config for HLT-enabled appliances




identification based on unique device id
static definition of devices, services (?)
Proprietary protocol, central control
prime target: domotica
Johan Lukkien
11-4-2001
EESI Embedded Internet Colloquium 17
Live-in




Zanussi (Electrolux, Sweden)
Home automation: integrated use of
telephone, powerline and cable
auto-config
central access point, remote control
Johan Lukkien
11-4-2001
EESI Embedded Internet Colloquium 18
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Use telephone, powerline
Four components: communication-link,
current meter, tele-link, digital adapter
Web Ready Appliance Protocol
auto-config for WRAP-enabled appliances
Console, web connected
Johan Lukkien
11-4-2001
EESI Embedded Internet Colloquium 19
Lonworks

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Echelon, fieldbus technology
philosophy: 3 networks (computer, control,
entertainment)
use many types of media
auto-config,
static typing of
devices
deployed in



homes
transportation
industrial automation
Johan Lukkien
11-4-2001
EESI Embedded Internet Colloquium 20
Internet?


Concerns the layers above the data-link
Until now: mainly supporting computers



not much use of alternatives like powerline
(is growing now)
little internet-use within the home
Configuration needs



IP address, network mask, router
address, domain name, domain name
server
TCP/IP stack
... + protocols on top of that
Johan Lukkien
11-4-2001
EESI Embedded Internet Colloquium 21
Auto-config issues

Level of discovery
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Definition of device
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static (list of known devices)
dynamic
Definition of services

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physical level (plugging, e.g.“network reset”)
network level (broadcasting)
static
dynamic (publish interface)
Centralized/distributed knowledge
Resulting network load
Johan Lukkien
11-4-2001
EESI Embedded Internet Colloquium 22
Technologies

Connecting:

IP auto configuration: setup a network
locally (integral part of IPv6, add-on of IPv4)

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choose a link-local address in the absence of
a DHCP server
no traffic beyond a router (IPv4, NAT)
Apple-talk, Win98
Services:



Jini (Sun, Java based)
OSGi (Java based)
Universal Plug ’n Play (Microsoft)
Johan Lukkien
11-4-2001
EESI Embedded Internet Colloquium 23
Jini (Sun)



Assuming network connection
Centralized information store: lookup
service
Upon plugging: discovery & join-in




discover lookup service
upload an object implementing the services
(driver)
Upon using: obtain driver from the lookup
service; use RMI
General classification of services (e.g.,
video source, display, ...)
Johan Lukkien
11-4-2001
EESI Embedded Internet Colloquium 24
Universal Plug ’n Play


Use IPv4 auto-config or DHCP
Simple Service Discovery Protocol

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Service Control Protocol

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
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service announcement
service request
device description: XML document
state variables
operations
Subscription on state updates
Optional user interface URL
Fully decentralized solution
Johan Lukkien
11-4-2001
EESI Embedded Internet Colloquium 25
Other developments



Work of the “zero-configuration
networking” Working Group within IETF
Service Location Protocol (supports
queries)
Lightweight Directory Service Protocol


to access shared information
....P
Johan Lukkien
11-4-2001
EESI Embedded Internet Colloquium 26
Conclusion


Growth path for (inter)networking
Internet pervasive

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Zero-configuration required as devices



but there’s room for a control network
connecting control to internet: gateway
grow in numbers
control each other
IP as platform


open standards
available software, infrastructure,
experience etc.
Johan Lukkien
11-4-2001
EESI Embedded Internet Colloquium 27