Program and deploy your SN in minutes  Program: Single System Image  “Write Once, Run… Wherever”  Each program runs on an SN “slice” i.e., a Virtual Sensor Network VSN Painless administration  Self-organizing, automated dispatch  Sensor network can grow or shrink as resources become available Install and run the Sensorium eXecution Environment (SXE) Resource Manager and Service Dispatcher do the rest Goal: The Sensor Network as the Computer Motivation and Scope Inexpensive networked sensing elements will be pervasively embedded in shared physical spaces (Sensoria). To fully harness Sensoria we must be able to easily build and deploy applications capable of gathering, interpreting, storing and responding to data from distributed sensors. 1. Provide scalable mechanisms for managing the networks and systems resources that these applications consume. 2. These resources must be composed, tasked and administered in some structured, extensible and maintainable fashion Enter the Sensor Network WorkBench:  snBench provides users with their own virtual Sensor Network via programming and run-time infrastructure enabling developers to easily specify and deploy distributed applications over a heterogeneous network of Sensing and Computing Elements. What sensors can I use and what functionality do they expose? SN Bench: the Life-Cycle of a SN App Program: High-level functional style specification language SNAFU glues together atomic operations. Compile: A SNAFU program is compiled into a Sensorium Task Execution Plan (STEP). Map and Link: Run-time support components break the STEP into smaller sub-STEPs that fit on available resources. Load and Execute: STEPs are dispatched to Sensor eXecution Environments (SXEs). SNAFU : SN Applications As Functions SSD/SRM : Service Dispatcher & Resource Manager SXE : Sensor eXecution Environments let img = snapshot(cam2) in trigger( (motion(img) && (2am<NOW<4am)), (img, ) SXE dispatch Example The user writes a SNAFU program that strings together the sensors and operations the user is interested in  alternatively, the user could use the graphical STEP IDE… The SNAFU program is compiled into STEP and the infrastructure does the rest! SN Bench: A Sensor Network Development WorkBench Michael Ocean, Azer Bestavros and Assaf Kfoury Extensibility  New sensing hardware, modality or functional abilities require simple Java class (interface) implementation  Programs use simple, high-level language and can immediately leverage new devices, types or capabilities. Reasonable cost  Programs are interpreted and executed by the run-time.  Computational overhead is reasonable and can be minimized by thoughtful implementation or direct compilation. STEP : Sensorium Task Execution Plan trigger cam2 snapshot motion clock4AM 2AM << && trigger cam2 snapshot motion clock4AM 2AM << && linkcompile SNAFU programs describe sensory data manipulated by a series of functions (i.e., a sensory data flow). Triggers specify temporally persistent queries (event monitoring & response). The explicit evaluation strategy for a SN app. Data percolates up from the leaves, demand travels down from the root. Concurrency and dependency are explicit. Resource management components solve graph partitioning/embedding for task assignment [see NetEmbed]. A run-time for sensors, SXEs accept partial STEP graphs and evaluate them.