• Consists of spatially distributed autonomous devices using sensors to monitor environmental conditions.

• Small physical size and low power consumption

• Concurrency-intensive operation• Limited Physical Parallelism and Controller

Hierarchy• Diversity in Design and Usage• Robust Operation

Constrained resourcesEfficient multitaskingFlexibility“Mote”-class devices• 10-100 kilobytes of code ROM• < 20 kilobytes of RAM

• Portability

• Flexibility

• Efficient

• Multitasking

• Networking (TCP/IP)

• Size

• Free and open source component-based operating system.

• Started as a collaboration between the University of California, Intel Research.

• Embedded operating system written in the nesC programming language.

• Event driven Operating System.• Application and Libraries are written using

nesC,a programming language.

• Specifically designed for WSN.• Event-driven OS.• Completely non-blocking.• Programs are built out of software

components.• Tasks are non-preemptive and run in FIFO

order. • Tiny OS code is statically linked.

• Open source, highly portable, multitasking operating system.

• Developed by Adam Dunkels at the Swedish Institute of Computer Science.

• First OS for sensor networks to provide TCP/IP.

• Protothreads, a extremely lightweight, stackless threads.

• Multitasking kernel

• Preemptive scheduling

• Managed Memory Allocator

• Protothreads

• TCP/IP networking, including IPv6

TINY OS CONTIKI OS

Event –driven OS with non-preemptive multitasking.

Event-driven OS with optional preemptive multitasking.

Static linking. Dynamic linking.

Written using nesC programming language.

Written using C Programming language.

• Network Embedded Systems C• Event-driven programming language used to

build applications for the TinyOS platform.• An extension to the C programming language• Designed to embody the structuring concepts

and execution model of TinyOS.

• Separation of construction and composition.

• Specification of component behaviour in terms of

set of interfaces.

• Interfaces are bidirectional.

• Components are statically linked.

• Designed to run on embedded devices used in

WSN.