The software components in WSNs include sensor operating systems and middleware as shown in figure below. The purpose of these is to ease the application development by providing network access and allowing support for heterogeneous platforms with hardware abstraction.
An operating system (OS) in a WSN is a thin software layer that logically resides between the node’s hardware and the application and provides basic programming abstractions to application developers.
Its main task is included:
1. Enable applications to interact with hardware resources.
2. Schedule tasks.
3. Arbitrate between application program and other services that try to seize resources.
4. Memory management, power management and File management.
5. Networking.
6. Enable users to develop, debug, and execute their own programs.
Modern sensor operating systems differ from conventional PC operating systems in a number of ways. These differences stem from the unique hardware and energy constraints typically encountered in sensor networking. The following points describe the general principles behind sensor operating systems.
I. Small memory footprint: Due to the resource constraints, an operating system should be as small as possible to leave space for applications.
II. Real-time operation: Sensor networks are inherently coupled with the real world, which sets timing constraints to the operation. In addition, network protocols are often time-sensitive. Both of these require real-time support to make right actions at the right time.
III. Energy management: As sensor nodes may operate on batteries, an OS should operate efficiently to reduce its energy overhead by e.g. shutting down unused peripherals.
المادة المعروضة اعلاه هي مدخل الى المحاضرة المرفوعة بواسطة استاذ(ة) المادة . وقد تبدو لك غير متكاملة . حيث يضع استاذ المادة في بعض الاحيان فقط الجزء الاول من المحاضرة من اجل الاطلاع على ما ستقوم بتحميله لاحقا . في نظام التعليم الالكتروني نوفر هذه الخدمة لكي نبقيك على اطلاع حول محتوى الملف الذي ستقوم بتحميله .
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