1. Welcome to the WeBS Retreat David Culler Eric Brewer, David Wagner Shankar Sastry, Kris Pister EECS U.C. Berkeley Intel Research @ Berkeley www.cs.berkeley.edu/~culler

2. 1/12/2002WEBS Retreat2 Outline What retreats are about Introductions Webs Technology Push Webs application opportunities Where we are now Research Challenges Overview of the Agenda

3. 1/12/2002WEBS Retreat3 What retreats are about 6 month project checkpoint –milestones, accomplishments, shortfalls –course correction Students refine communication and investigation skills –interested benign audience, lots of feedback In depth exchange with industrial collaborators –discussion and feedback –close with feedback session Build team and cement connections

4. 1/12/2002WEBS Retreat4 Introductions the start of a 3-day discussion...

5. 1/12/2002WEBS Retreat5 Technology Push CMOS advance not just Moore’s law –miniaturization, lower cost, lower power, complete systems MEMS bringing rich array of cheap, tiny sensors –tiny actuators too Communication –low-power radios, optical,... Power –Solar, vibrational, parasitic,... => microscopic Processing, Storage, Communication and interaction with the physical world Can foresee computational fabrics, materials, jewelry, clothing, insects, dust LNA mixer PLL

6. 1/12/2002WEBS Retreat6 Application Pull Dense instrumentation in space and time –environmental monitoring and management –life sciences revolution –emergency analysis and response –surveillance and security In situ monitoring and management –condition-based maintenance Ubiquitous computing environments –infer intent from observed action & context, reactive environment Robotic swarms

7. 1/12/2002WEBS Retreat7 Bridging the Technology-Application Gap Power-aware, communication-centric node architecture Tiny Operating System for Range of Highly- Constrained Application-specific environments Network Architecture for vast, self-organized collections Programming Environments for aggregate applications in a noisy world Distributed Middleware Services (time, trigger, routing, allocation) Techniques for Fine-grain distributed control Demonstration Applications

8. 1/12/2002WEBS Retreat8 Where do we stand now?

9. 1/12/2002WEBS Retreat9 The de facto platform for sensor nets Developed a series of wireless sensor devices TinyOS concurrency framework Messaging Model Networking stacks (RF and Serial) Multihop routing Several Key components –sensing, logging, data filters, broadcast Simulation tools

10. 1/12/2002WEBS Retreat10 Tiny OS Concepts Scheduler + Graph of Components –constrained two-level scheduling model: threads + events Component: –Commands, –Event Handlers –Frame (storage) –Tasks (concurrency) Constrained Storage Model –frame per component, shared stack, no heap Very lean multithreading Efficient Layering Messaging Component init Power(mode) TX_packet(buf) TX_pack et_done (success ) RX_pack et_done (buffer) Internal State init power(mode) send_msg (addr, type, data) msg_rec(type, data) msg_sen d_done) internal thread Commands Events

11. 1/12/2002WEBS Retreat11 Application = Graph of Components RFM Radio byte Radio Packet UART Serial Packet ADC Tempphoto Active Messages clocks bit byte packet Route map routersensor appln application HW SW Example: ad hoc, multi-hop routing of photo sensor readings 3450 B code 226 B data Graph of cooperating state machines on shared stack

12. 1/12/2002WEBS Retreat12 Many Research Groups on board UCB –NEST –SensorWeb –Blackout –Glaser structures –CBE –BFD –BRWC UCLA USC Rutgers winlab Intel Bosch Crossbow U Wash Rutgers UIUC NCSA U Virginia Ohio State UCSD Dartmouth MIT Accenture and soon many more

13. 1/12/2002WEBS Retreat13 Handful of demonstration applications 29 Palms Cory Hall network –½ million packets over 3 weeks Surge network and environment display CBE (???) Glaser Shakes Granlibakken retreat watcher => need to get greater application focus more real and long lived more dynamics extract architecture and create framework

14. 1/12/2002WEBS Retreat14 Key Experience Really good at building tinyOS subsystems –non-blocking, split-phase event structures Internalized the “state of constant change” paradigm –ex: maintain routing tree by constantly rebuilding it –soft state that is always suspect –simple one-way protocols Operating in the aggregate Simple mechanisms to accomplish large goals –MAC, ATC Out of the box on networking abstractions –Low-power listen, wake-up, statistical sampling, weighted aggregation Understanding of large scale dynamics

15. 1/12/2002WEBS Retreat15 Pushing Scale

16. 1/12/2002WEBS Retreat16 Good stated agenda with NEST Develop sequence of open experimental platforms –basic services (time synch, trigger) Develop Challenge Application for NEST FSM high-concurrency programming environment Infrastructure support Adversarial simulation Macroprogramming unstructured aggregates HW platform SW platform coordination services synthesis services composition services Challenge Application

17. 1/12/2002WEBS Retreat17 Secure Language-Based Adaptive Service Platform for Large-scale Embedded Sensor Networks New Ideas Small, flexible, low-cost, low-power, wireless embedded sensor devices Tiny event-driven, robust, open component OS for NEST devices - mcast, AM, prune algorithmic primitives FSM high-concurrency prog. env. Resilient aggregation - for security and other noise Macroprogramming unstructured aggregates Adversarial Simulation Impact Enable creation of embedded distributed syst. of unprecedented scale and role - 1,000s of tiny networked sensors Enable new classes of applications integrated with physical world - Greatly simplify creation of distributed systems at extreme scale (HW & SW) - fine-grained distributed control Accelerate prototyping and evaluation of new coord. & synthesis algorithms Enable new, robust basis for distributed, embedded software thru platform design & novel tools for simulation and visualization Drive NW sensor challenge applications Schedule June 01 Start June 02June 03 June 05 End June 04 OEP1 10x100 kits OEP2OEP3 OEP1 defn OEP1 eval OEP2 proto FSM on OEP1 OEP2 analysis chal. app defn log & trace adv. sim macro. lang design OEP2 platform design OEP3 platform design lang based optimize & viz final prog. env chal app & evaluation David Culler, Eric Brewer, David Wagner Shakar Sastry, Kris Pister UC Berkeley

18. 1/12/2002WEBS Retreat18 Wealth of Research Challenges Large numbers of highly constrained (energy & capability), connected devices –able to be casually deployed in infrastructure (existing or to be created) –imperfect operation and reliability –operating in aggregate Create a suite of platforms to initiate the cycle of refinement New family of issues across all the layers application service network system architecture technology mgmt / diag / debug algorithm / theory prog / data model

19. 1/12/2002WEBS Retreat19 Technology Challenges Ultra low power data paths, ADC,... Radio (CMOS passives, SW, UWB) Optical communication Sensors & Actuators near Zero-power ‘listen’ Basis for ranging & localization Power harvesting and storage –point of sustainable operation Integration into everyday devices

20. 1/12/2002WEBS Retreat20 Node Architecture Challenges General purpose, application specific optimization Balance and functionality thresholds Physical vs virtual parallelism –controller, interconnect hierarchy for network embedded dev. Passive vigilance Self diagnosis and watch-dog Subsystem abstractions Packaging, packaging, packaging...

21. 1/12/2002WEBS Retreat21 Operating System Challenges Robust, efficient concurrency in situ, dynamic code communication primitives & capabilities scheduling discovery and configuration security programming model synthesis and optimization simulation and testing Security & Privacy

22. 1/12/2002WEBS Retreat22 Networking Challenges Incorporating place and time Channel management –coding, MAC, hopping Connectivity Management & Topology formation Routing –richness, subprimitives, redundancy Protocols Architecture –storage, retransmission, naming/addressing –hierarchy Multicast / Aggregate operation Scheduling Security

23. 1/12/2002WEBS Retreat23 Service Challenges Discovery –who are you, what do you have, what do you do, where am I? Recruitment of resources Time synchronization Localization Routing services Storage Services Dynamic allocation of resources Negotiation of roles Service Architecture

24. 1/12/2002WEBS Retreat24 Distributed Control Challenges Closed-loop at many levels network in the feedback loop –observation path –control path Shift from large centralized analysis to many small points of processing Distributed constraint solving Phase-transition characteristics

25. 1/12/2002WEBS Retreat25 Programming Challenges Analysis and synthesis of robust event-driven structures Optimization for power, jitter, delay bounds In network programming and code management Nodal programming model Programming unstructured aggregates

26. 1/12/2002WEBS Retreat26 Application Challenges It’s all about data –infrastructure data vs in-network data –deep connections between queries and content-based routing –compression vs robustness Data models for truly long-running queries –when you don’t have much storage and BW,... Cooperative processing –multimodal and multi-lateration Everything has error terms What are the right higher-level abstractions Privacy

27. 1/12/2002WEBS Retreat27 Algorithms Classic distributed alg’s face tiny nodes and highly dynamic network structure –power constrained Localization Scheduling Fine-Grain Inverse problems Imaging Constructive foundations of self-organization Understanding how an extreme system is behaving and what is its envelope –adversarial simulation

28. 1/12/2002WEBS Retreat28 Overview of Agenda (monday) Introductions (Culler chair) –Overview of the Project (David Culler) –Closing the loop - Control and Applications (Shankar Sastry) –NEST MICA Platform architecture (Jason Hill) Dinner Demo presentations (Brewer chair) –Building-wide monitoring of environment and things (Robert Szewczyk, Anind Dey) –Cheap robots & Smart Dust (Mike Scott & Sarah Bergbreiter) –ROBOMOTE (Gaurav Sukhatme, USC) Play

29. 1/12/2002WEBS Retreat29 Overview of Agenda (Tuesday) Sensor Processing and Simulation (Sastry chair) –NEST Sensor platform (Alec Woo) –Localization (Kamin Whitehouse) –Visualization and Simulation (Phil Levis) Breakout Session - Breakthough Opportunities and Challenges – Radical new applications –Key Algorithmic / Theoretical Problems –Novel networking / Systems Design 12:00 - 4:00 Lunch Recreation and Team Building Networking and Applications (Pister Chair) –Net dynamics (Deepak Ganesan) –Mote geocast (Joe Polastre& Rachael Rubin) –Tracking (Bruno & Luca) –Security, crypto, beaconing (Adrian Perrig) - key distr, auth Dinner Panel: Applications of Networked Embedded Systems Technology (Wagner chair) –Falk Herman, Bosch –Lakshman, Intel - Ubiquitous Office Environments – Kris Pister, Structures, Fire, and all that –Alan Mainwaring, Intel - What the field biologists want

30. 1/12/2002WEBS Retreat30 Overview of Agenda (Wednesday) 8:30 - 9:30 Open Mic 9:30 - 10:00 Break to check out 10:00 - 11:00 Report from Breakouts 11:00 12:00 Visitor feedback