Rutgers, The State University of New Jersey D. Raychaudhuri ray@winlab.rutgers

1. Research Challenges in Sensor Nets & Pervasive Systems, … and some observations on writing effective grant proposalsNSF NOSS Info Mtg, Oct 19, 2004 Rutgers, The State University of New Jersey D. Raychaudhuri ray@winlab.rutgers.edu www.winlab.rutgers.edu

2. Some Trends • < 2% of all CPUs go into PCs • ~ $1/1GB (300 songs, 1 movie) • Sensor + radio on single chip (SoC) ~$10  $1 • Internet of Things (M2M – machine 2 machine) • Revenue: $2.5B / 2004, $10B / 2008 (FocalPoint) • Nestlé: hundreds of ice-cream vending machines • 1,000 railcars in Britain transmit maintenance data • Philips: Plans to link light fixtures using ZigBee radios • Wireless sensor nets & pervasive computing migrating from research to early usage….

3. Wireless Network (R)Evolution Increasing use of fast, low-cost short-range radios Heterogeneous systems with multiple radio standards (3G, 4G, WLAN, UWB..) Increasing use of unlicensed spectrum and dynamic sharing methods Self-organizing ad-hoc access networks including mesh, home & sensor nets Uniform IP core network as backbone New socket & network programming models MSC Internet (IP-based) Public Switched Network (PSTN) Generic mobile infrastructure Custom Mobile Infrastructure (e.g. GSM, 3G) GGSN, etc. BSC BTS WLAN Access Point BTS Infostation cache WLAN Hot-Spot High-speed data & VOIP Relay node Voice (legacy) Ad-hoc network extension High-speed data & VOIP CDMA, GSM or 3G radio access network VOIP (multi-mode) Broadband Media cluster (e.g. UWB or MIMO) Low-tier clusters (e.g. low power 802.11 sensor) Today Future

4. Sensor Nets & Pervasive Systems Pervasive Application Agents Compute & Storage Servers User interfaces for information & control Mobile Internet (IP-based) Overlay Pervasive Network Services 3G/4G BTS Sensor net/IP gateway GW Relay Node Sensor/ Actuator Ad-Hoc Sensor Net A Ad-Hoc Sensor Net B Virtualized Physical World Object or Event

5. Pervasive Systems: Applications • (Frictionless Capitalism)**2 • Find goods and services on your PDA as you walk through town • Walk into your dept store and pick up what you need (no cashier!) • “Smart” Transportation systems • get routed around traffic jams in real-time • receive collision avoidance feedback, augmented reality displays • be guided to an open parking spot in a busy garage • Airport logistics and security • Walk on to your plane (except for physical security check) • Find your (lost) bags via RFID sensors • Airport authorities can screen passenger flows and check for unusual patterns • Smart office or home • Search for physical objects, documents, books • Maintain a “lifelog” that stores a history of events by location • know where your co-workers and family members are

6. Pervasive Systems: Properties • Robust operation • Self-healing, self correcting • Probabilistic guarantees, soft state • Ad-hoc & heterogeneous • Multiple owners and objectives • Groupings based on dynamic proximity and common goals • Data Centric • Data and related context more important than IP address... • Open, evolving • Re-purpose, (unplanned) emerging behavior

7. Pervasive Systems: Key Technologies • Sensors • Tiny, low-power, integrated wireless sensors (hardware) • Embedded OS and networking capabilities (software) • Ad-hoc wireless networks • Self-organizing sensor networks • Scalable, capable of organic growth • Interface to existing 3G/4G cellular and WLAN • Power efficient operation • Sensor network software • Dynamic binding of application agents and sensors • Real-time orchestration of sensor net resources • Robust, secure and failsafe systems • Augmented reality, new displays, robotics, control, information processing... emerging computer hardware category, optimized for size/power new type of wireless network without planning or central control fundamentally different software model - not TCP/IP Windows or Unix!! ...related application technologies

8. Affinity Groups Autonomous Agents <> <> <> Overlay Service Network <> <> <> <> ••• Ad-Hoc Data Network ••• ••• ••• ••• ••• ••• Sensors & Actuators Pervasive Systems: Layered Model

9. Sensor Networks: Software Model • Sensor net scenarios require a fundamentally new software model (…not TCP/IP or web!!): • Large number of context-dependent sources/sensors with unknown IP address • Content-driven networking (…not like TCP/IP client-server!) • Distributed, collaborative computing between “sensor clusters” • Varying wireless connectivity and resource levels Pervasive Computing Application Agent 2 Agent 3 Agent 1 Sensor Net Software Model Overlay Network for Dynamic Agent <-> Sensor Association Sensor Cluster B Run-time Environment (network OS) Sensor Cluster A OS/Process Scheduling Resource Discovery Ad-hoc Routing

10. Sensor Networks: Ad-Hoc Wireless for Basic Connectivity • Self-organizing ad-hoc networks serve as the low-tier infrastructure for pervasive systems. • Maturing topic, but research opportunities do exist, for example: • Better MAC algorithms for ad-hoc mode • Topology discovery and self-organization protocols • Scaling, hierarchies and spectrum reuse • Supporting QoS at MAC and routing layers • Cross-layer transport and routing protocols Access Point Wireless link with varying speed and QoS Local Interference and MAC Congestion Sensor Relay Node Dynamically changing Network topology

11. Sensor Networks: Overlay Services for Dynamic Binding • Overlay networks can be used for dynamic binding between sensor devices, end-users and application programs • Use of XML or similar content descriptor to specify sensor data and application profile • “Layer 7” overlay network (implemented over IP tunnels) provides binding service between producers (sensors) and consumers (servers, users) Interest Profile XML Descriptor Overlay Router B Overlay Router A Content Consumer Content Provider

12. Sensor Networks: Process Orchestration • Sensor net applications can involve complex real-time interactions between numerous network entities • Data from each sensor is not necessarily a continuous field measurement • Requires context & location aware binding of application with sensors & actuators • Orchestration of computing and network resources in real-time Allocate closest available space Look for parking space subscribe (plate-num, car-type, student) Parking Center Data Center Monitor incoming car Check registration, Deduct parking fee Check parking space availability Look for parking space: subscribe (plate-num, car-type, IAB guest) Incoming Car ( check ID: Registered student/faculty/staff, guest reservation? Fee deduction) Campus Parking Service Monitor available space Figure courtesy of Prof. Manish Parashar

13. Pervasive Systems: Information Management • Multi-tiered aggregation of • data into actionable information • significant technical challenges in distributed data processing... Sensor Figure courtesy of Dr. Max Ott

14. Sensor Systems: Performance Evaluation • Significant challenges in validation and performance evaluation of sensor systems • Large scale ~100’s to 1000’s of nodes • Need for realistic wireless connections • Should incorporate CPU processing limitations • Energy as a key performance metric • Systems with emergent behavior • Motivates scalable simulation models, emulator systems and real-world testbeds for sensor nets

15. NSF Community Testbeds: ORBIT Radio Grid

16. NSF Community Testbeds: ORBIT Field Trial System

17. Some NOSS Related Research Topics: • Sensor network software architecture • Ad-hoc network protocols: energy, cross-layer, hierarchies... • Distributed OS & new sensor net API’s • Data-centric network services & programming model • Location-aware networking & applications • Location determination in wireless networks • MAC and routing protocols which exploit location • Location middleware and applications • Privacy & security in sensor nets • Hiding location and context for privacy • Developing trust in ad-hoc networks • New security models for sensor applications • Large-scale sensor nets • Scalability of large-scale networks • Stability under different types of traffic overload and failures • Emergent behavior of autonomous protocols & applications

18. Writing Effective Systems Proposals Important Disclaimer: This material is being provided the request of the NSF program officer with the objective of assisting new faculty in getting started with writing responsive proposals. The author recognizes that the outlined approach is by no means unique and is not intended for experienced NSF-funded researchers who are likely to have their own well-developed methods.

19. Preliminary Work: Initial Preparations • Start early: read NSF call for proposals carefully as soon as it is issued and understand the research direction/emphasis • Critically evaluate your research concepts vs. scope of CFP to make sure there is a fit • Start to study and define a “systems vision” corresponding to the research focus you have in mind • Builds understanding of system scenarios and related open problems • Helps clarify practical constraints of scenarios under consideration • Provides a holistic framework for your proposal • Valuable step even if your research idea is more narrowly focused • …often requires a prior discussion and research investment of ~1 yr+ to respond to the CFP for a new area

20. Step 1: The Research Idea • Define your specific research theme in context of the systems vision discussed earlier • What specific problem is being solved and exactly how does it fit into the system under consideration? • Carefully evaluate importance of your ideas relative to prior work and “big picture” of target system • Define your research contribution clearly in terms of new technologies, system models, algorithms, methodology and how it helps solve open problems • Is this a conceptually new idea and does it break new ground in the area? • Is this a sincere attempt to solve a new research problem, or an attempt to recycle a favorite model or methodology?

21. Step 1: The Research Idea (contd.) • Evaluate the functional and performance benefits of the proposed idea, and back it up with preliminary results if at all possible: • What are the system level performance gains ..10%, 50%, 100%, 10x, 100x? • If the benefits are more complex (e.g. ease of implementation, software robustness or scalability), how would you assess these advantages? • Is this a sincere attempt to solve a new research problem, or an attempt to recycle a favorite model or methodology? • Be critical with your own work…! Discussions with colleagues, mentors always beneficial.

22. Step 2: The Research Project • When the research idea has passed internal critical review, you need to work on defining the project • Remember that defining the research project is not the same as simply describing the research idea: • Requires clear definition of scientific and technical objectives of the project • Does the project result in: analysis, modeling, system design, hardware design, protocol definition, performance analysis, proof-of-concept prototyping, …? • What methodologies are used for the project? • What are the metrics used to determine whether the proposed idea works? • What specific technical results are expected as the outcome? • Is this a collaborative project? If so, identify respective roles and interfaces. • Collaboration is often the best way to address a complex research problem…

23. Step 3: The Research Plan • Once you have defined the research project in terms of high-level objectives, create a solid project plan: • Identify major project sub-tasks and their milestones; this is useful even for a simple analytical project and mandatory for anything more complex • Make bottom-up estimates of the time required for each subtask taking into account planned level of resources • Identify equipment, simulation software, testbeds, etc. required for project • Identify potential delays/risks and dependencies between tasks • Construct an overall schedule and set of milestones based on above • Identify broader impacts, educational activities & other factors required by NSF • Use the this information to prepare a project budget (…which should reflect the project plan and not be a template for x summer mo & y graduate students)

24. Step 4: The Research Proposal • The research proposal follows nicely once you have the content from the previous slides: • Technology context & system scenarios under consideration • Main research idea, its relevance and competitive evaluation • Research project as defined by objectives, methodology, results • Research plan, schedule & budget • References • Writing the proposal is, of course, the final important step • Prepare an early draft & leave time for discussion and improvement • Rewrite again and again for clarity, logical flow and content • Be concise and avoid using jargon to the extent possible • Never cut-and-paste from other material! • Get internal peer-review, collaborate in writing and make multiple revisions