1. Web Enabled Devices & home networks
Johan Lukkien
programme leader “home networks”
Eindhoven Embedded Systems Institute
Eindhoven University of Technology

2. 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

3. Embedded Systems evolution
hardware replaces software
functionality
features
digitisation and manipulation of signals
configuration/programming of systems from outside
completely networked systems
increase in networking
Johan Lukkien

4. Evolution of embedded networking
Network aware: Information retrieval
from the system in a rudimentary fashion
Status information: errors, wear, use
Using existing connections and resources already available within the system
Off-line analysis of data
Transport: telephone, Internet
Advantage:
remote diagnosis
Network central: Adapt product design with
respect to the network connection
Integrate network functions with embedded hardware and software
Standardisation of connections, protocols
Advantage:
service: access to embedded software: debugging, replacement, sell features
owner: standardisation, new software
Evolution of embedded networking
Network connected: On-line connection with
the system
Put control hardware/software next to the embedded system
Interaction!
Advantage:
service: diagnostics, leasing of appliances
owner: remote monitor & control, security, production-control, fleet maintenance
Fully networked: the functionality is defined
by the network
Devices controlling each other
Intelligent environments, all equipment in the background (Philips: “ambient intelligence”)
Advantage:
service: new markets
owner: ease of use, comfort, integration
Standalone: embedded
hardware and software:
invisible
are, in fact, an implementation aspect of the product
time
standalone
fully networked
network aware
network connected
network central
Johan Lukkien

5. The effect of Internet ..... + information exchange!!
Data transport (large distance)
Standards: ftp, , ...
Distributed access
Interoperability
Standards for offering services: Jini, UPnP, OSGi
Platform for
data exchange
integration
time
standalone
fully networked
network aware
network connected
network central
Standards for
software architectures
communication: HTTP, Java, TCP, UDP, ....
visualisation: browsers
Global addressing
information exchange!!
Johan Lukkien

6. Technical background
Moore: number of transistors/mm2 doubles every 18 months
processing power and memory capacity become abundant
Metcalfe: de “value” of a network is proportional to the square of the number of nodes
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

7. 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

8. Architecture Request connection Program code Remote user sensors UDP
actuators
Applet
ES-Server
HTTP
(applet code)
HTML browser
HTTP server
Johan Lukkien

9. Components HTTP server:
standardized access: URL
code download: Java applet
ES server: provide “driver interface” for embedded system
HTTP browser (client):
setup contact
run machine-independent code
“programmable interactive remote control”
Applet:
interface to user
driver of ES
Johan Lukkien

10. Trade-offs Connection 1: Internet protocol implicit: within applet
Observer
Embedded
System
Actuators
&
Sensors 1 2
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. Trade-offs Connection 2: proprietary
Observer
Embedded
System
Actuators
&
Sensors 1 2
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

12. Example: ubicom room control
Devices not networked individually
Johan Lukkien

13. Example: EESI coffee maker
Switch and heat control not networked individually
Request connection
Program code
Remote user
Johan Lukkien

14. Trade-offs Connection 2: proprietary
Observer
Embedded
System
Actuators
&
Sensors 1 2
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?
Criterion supporting intelligence at A&S
Hardware is locally necessary
safety, real-time control (don’t distribute safety issues across an unreliable network)
establishing relationship actuator-sensor
process sensor input
Criteria against intelligence
Single function (ES is already dedicated)
Logical unit controlled from ES
No power available
Johan Lukkien

15. 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

16. Fully networked devices
Separate user interface and driver functions
It must be simple to attach to the network
lightweight
easy to handle
Zero configuration connection
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

17. Zero-config for HLT-enabled appliances
(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

18. Live-in Zanussi (Electrolux, Sweden)
Home automation: integrated use of telephone, powerline and cable
auto-config
central access point, remote control
Johan Lukkien

19. 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

20. Lonworks 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

21. 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

22. Auto-config issues Level of discovery Definition of device
physical level (plugging, e.g.“network reset”)
network level (broadcasting)
Definition of device
static (list of known devices)
dynamic
Definition of services
static
dynamic (publish interface)
Centralized/distributed knowledge
Resulting network load
Johan Lukkien

23. Technologies Connecting: Services:
IP auto configuration: setup a network locally (integral part of IPv6, add-on of IPv4)
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

24. 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

25. Universal Plug ’n Play Use IPv4 auto-config or DHCP
Simple Service Discovery Protocol
service announcement
service request
device description: XML document
Service Control Protocol
state variables
operations
Subscription on state updates
Optional user interface URL
Fully decentralized solution
Johan Lukkien

26. 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

27. Conclusion Growth path for (inter)networking Internet pervasive
but there’s room for a control network
connecting control to internet: gateway
Zero-configuration required as devices
grow in numbers
control each other
IP as platform
open standards
available software, infrastructure, experience etc.
Johan Lukkien