EMBEDDED COMPUTATION MEETS THE WORLD WIDE WEB Gaetano Borriello & Roy Want Communications of the ACM, May 2000 Presented by Lee, Richie (Chi-Chiang)

Presentation Outline Introduction Communication Technologies Device Technologies Applications Conclusion

Introduction Two important trends are converging: (1) The computer industry’s ability to squeeze ever-more transistors into an ever-smaller area of silicon (2) The proliferation of wired and wireless networking We have migrated our work to electronic media The internet is the most vital of all the computational components

Introduction (Cont.) 1970s: (1) ARPANET - It was created by the United States Defense Advanced Research Project Agency. (2) NSFNET - A wide-area network developed under the auspices of the National Science Foundation.

Introduction (Cont.) 1980s: (1) The name INTERNET was coined. (2) Unified by the TCP/IP protocol set. (3) Moore’s Law – It predicts that the number of devices that can be fabricated on a chip doubles every 18 months.

Introduction (Cont.) Today: A microcontroller + 1 megabyte memory == A desktop computer in 1985 New standards and mass-produced transceivers continue to drive down the cost of wireless connectivity

Communication Technologies The technologies – They are deriving the revolutionary reorganization of our information systems Standardized ubiquitous protocols – They gather & deliver & present information to user services through networks.

Embedded Web servers The Web’s basic functionality: (1) Enables client programs and browsers to fetch Web pages and display them (2) Hyperlinks can reference other local or remote files to that site (3) A Link may reference a CGI script Who can build the smallest Web server?

Hydra, Xerox PARC’s embeddable Web server

Embedded Web servers (Cont.) Designed at Xerox PARC in 1998 Its connector attach to a 10baseT Ethernet It runs the Spyglass Web server on top of the VxWorks operating system 16MB DRAM & 1MB flash memory

Dallas Semiconductor’s Tini Web server

Embedded Web servers (Cont.) Commercial embeddable Web servers Some Web-server designs aim in a totally different direction, using a serial line rather than a direct Ethernet connection

A Web server on a Microchip PIC processor

A Web server on a FairchildACE1101MT8 processor

Embedded Web servers (Cont.) The challenge: implement as little as possible of the HTTP/TCP/IP protocol stack to meet the protocol standards while remaining small

Java, applets, and Jini The java programming model provides a way to bring computation to the client The code can execute locally by the local JVM Java applets enable a device to export its interface to a secondary machine

Java, applets, and Jini (Cont.) Jini Network Technology: - Developed by Sun Microsystems - Network-centric computing - Enable local appliances to be located by client processes - Form ad hoc communities of devices

Jini Network Technology Enable devices to plug together to form an impromptu community Lookup service: When a device plugs in, it goes through an add-in protocol. (1) Discovery - The device first locates the lookup service (2) join-in - then uploads an object that implements all of its services' interfaces

Wireless Connectivity Among embedded devices is extremely desirable Allow unencumbered mobility and dynamic ad hoc connection For example: - Bluetooth - Infrared communication - Human-body-based communication schemes

Bluetooth A large consortium of computer and consumer electronics companies Provide a low-cost wireless solution for connecting components separated by no more than several meters Enable links between mobile computers, mobile phones, portable handheld devices, and connectivity to the Internet Data rate around 721 Kbps

Infrared communication As standardized by the Infrared Data Association (IrDA) Data rate ranging from 9600bps to 4Mbps The standard tried to encompass too many operating modes Line-of-sight operation

Human-body-base communication schemes Sending low-power data signals through a user’s skin For private communication and device selection by touching or holding

Device Technologies MEMS sensors Tags Location, tracking, sensing

MEMS sensors Microelectromechanical systems - An important solution to sensing, integrating computation and communication Made from novel mechanical structures constructed directly from silicon A common commercial application: - The accelerometer for controlling deployment of airbags

Photomicrograph of a MEMS accelerometer from Analog Devices

Tags The automatic identification industry Radio frequency identification (RFID) Electronic tags: - For tracking everything from packages to livestock - Now containing onboard memory - Have anticollision mechanisms to allow multiple e-tags to be read in the same space

Texas Instruments’ Tag-it system

Location, tracking, sensing The global positioning system (GPS) - Provide high-accuracy location data Indoor location sensing Tagging technologies - Detect an object’s presence and its position

Applications Home automation Experiment capture Health monitoring

Home automation Smart house - A long-sought vision of the future A prototypical example - Digital camera Many special challenges

Experiment capture Three main obstacles: (1) No unified model for integrating the knowledge of cell chemistry and mechanics (2) Experiments can’t be completely recorded (3) The lack of publication for the majority of experiments Embedded Web servers can connect laboratory instrumentation to the Web

Health monitoring Ubiquitous sensors and internetworking Provide chemical, temperature and physiology data Collected by a embedded Web server over an RF link New drugs along with their monitoring sensors and releasing actuators Personalized drug dosages and mixtures

Conclusion Embedded processing is already powerful enough to tackle the real-world applications Wireless and wired networking is increasingly ubiquitous Achieve the interconnection of our physical and virtual worlds Many challenges remaining