Protocol Kit

Modular Software Architecture

The s-net® protocol technology has a modular architecture and enables an energy-saving and secure multi-hop data communication in wireless sensor networks. The proprietary media access protocol SlottedMAC is the key component and combines the efficiency advantages of a time division multiple access system (TDMA) with the scalability and flexibility of contention based protocols. Thus, a self-sufficient, batterybased operation of wireless sensor networks with low latency (delay time) is guaranteed.

Flexible and extremely energy-saving platform for individual customer applications

With regard to the various requirements of the different applications, a system environment and a service-oriented architecture for sensor networks was developed with s-net®, which can be run on radio nodes which are particularly limited in resources. In doing so, the sub-functionalities of a node are realized in the form of functional components or services which can be found and used by other components. This software architecture presents a flexible platform for the creation of individual customer applications. Thanks to a flexible parameterization of the protocol properties (for various node densities, networking depths and data throughputs) the protocol can be adapted to different application areas. By a time synchronization of the network and time division multiple access communication a long operating time is achieved for battery operated systems.

Intermeshed and secure data communication

The dynamic formation and self-organization of the network topology allow low configuration outlay, low maintenance and a high level of robustness. The nodes communicate bidirectionally and organize themselves along a tree structure. Multi-hop communication with scalable range ensures fast data transmission through the network. Furthermore, it is possible to explicitly send data to single nodes, but also to a whole group of neighboring nodes. For the secure data transfer of important data packets, a security mechanism is available. This mechanism signals the successful reception to a sending node. If this signal is not transmitted the packet is sent again. This process is repeated until a configurable threshold.

Inherent localization for location-based task processing

The intermeshed networking creates the basis for accurate localization of sensor nodes within the s-net® network. Based on an enhanced WCL algorithm (weighted centroid localization), the sensor node independently calculates its own position from the positions of all received nodes. As the position is calculated directly on the node, applications can also trigger an alarm without network communication, e.g. in the case of theft.

A description of the most important components you will find here .

• Product Information Protocol Kit [ PDF 75KB ]

Hardware Reference Design

In order to be able to achieve extremely long-life battery operated systems for all sensor network platforms from the Fraunhofer IIS the lowest possible energy consumption was aimed for during the design process. For self-contained battery systems, we draw on key technologies from the power management and energy harvesting sectors.

We offer you to adopt the hardware reference designs of the Fraunhofer IIS s-net® sensor node platforms. For most applications the wireless modules can be employed with no modifications. But we also offer a solid starting point for a custom tailored solution. System properties, sensor technology, interfaces and design can be individually adjusted.

The s-net® S3 platform is the Fraunhofer IIS's latest sensor node platform. It was developed using modern, efficient and inexpensive components. The microcontroller's extended memory will be particularly helpful in creating novel, sophisticated sensor network applications.

Our wireless modules enable the implementation of complex wireless sensor networks, but can also be used in simple telemetric applications. Fields of application comprise distributed data acquisition, smart objects or positioning purposes.

An overview of our existing hardware solutions can be found here .

Evaluation-Kits

Our Evaluation-Kits allow an evaluation of the suitability of the s-net® protocol stack für your wireless sensor network application. If special modifications are required Fraunhofer IIS also offers tailored Evaluation-Kits.

Functionalities of the s-net® Evaluation-Kit »DATA«

Evaluation-Kit »DATA« consists of a master node and five sensor nodes which are able to autonomously organize themselves in a multi-hop topology. In this sensor network data can be transmitted between the sensor nodes and a master node which is connected to a computer. The multi-hop ability of the s-net® protocol stack allows the coverage of an area which is larger than the radio range of a single node.

To demonstrate the functionalities of the s-net® sensor network, a sample application is pre-installed on all sensor nodes. Additionally you may transmit your custom data packets via the multi-hop topology from the sensor nodes to the master node. By a specially designed graphical user interface the s-net® nodes can be operated and configured by the user. This way your scheduled applications can be tested in their intended area of application, whether if it’s measuring, monitoring or controlling tasks.

The Evaluation-Kit contents:

• Product Information Evaluation Kit »DATA« [ PDF 240KB ]