Web Enabled Devices & home networks

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 11-4-2001

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 11-4-2001

4. 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 • Network connected: On-line connection with • the system • Put control hardware/software next to the embedded system • Interaction! • http://aquarium.eesi.tue.nl • 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: http://www.research.philips.com/generalinfo/special/ambintel/index.html • service: new markets • owner: ease of use, comfort, integration • Standalone: embedded • hardware and software: • invisible • are, in fact, an implementation aspect of the product network central network central network aware network aware time standalone standalone network connected network connected fully networked fully networked Evolution ofembedded networking Johan Lukkien 11-4-2001

5. network central network central network aware network aware time standalone standalone network connected network connected fully networked fully networked The effect of Internet ..... + information exchange!! • Data transport (large distance) • Standards: ftp, email, ... • Distributed access • Interoperability • Standards for offering services: Jini, UPnP, OSGi • Platform for • data exchange • integration • Standards for • software architectures • communication: HTTP, Java, TCP, UDP, .... • visualisation: browsers • Global addressing Johan Lukkien 11-4-2001

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 11-4-2001

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 11-4-2001

8. Program code Architecture Request connection Remote user sensors UDP actuators Applet ES-Server HTTP (applet code) HTML browser HTTP server Johan Lukkien 11-4-2001

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 11-4-2001

10. Trade-offs 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 11-4-2001

11. Trade-offs 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 11-4-2001

12. Example: ubicom room control Devices not networked individually http://www.ubicom.com Johan Lukkien 11-4-2001

13. Request connection Program code Example: EESI coffee maker Switch and heat control not networked individually Remote user Johan Lukkien 11-4-2001

14. Trade-offs 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 11-4-2001

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 11-4-2001

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 11-4-2001

17. (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

18. 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

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 11-4-2001

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 11-4-2001

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 11-4-2001

22. Auto-config issues • Level of discovery • 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 11-4-2001

23. Technologies • Connecting: • 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 11-4-2001

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 11-4-2001

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 11-4-2001

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 11-4-2001

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 11-4-2001