Technology Overview

Ambient Systems was founded in 2004 by senior researchers from Twente University who had been leading the European research project EYES on energy efficient sensor networks. This project conducted breakthrough research on the architecture and technology needed to build self-organizing and collaborative sensor networks using reconfigurable smart sensor nodes, which are self-aware, self-reconfigurable and autonomous.

During EYES and subsequent research projects, the principles of Ambient’s wireless mesh networks were developed:

• Multi-hop Ambient Networks are multi-hop, enabling the communication of two nodes that are not in each other’s radio range by relaying data through intermediate nodes.

• Self-organizing The network is self-organizing, meaning that the whole network setup is automated. MicroRouters and SmartPoints have the ability to discover and join the network without configuration. Also, the network dynamically adapts to changes like moving nodes or adjusted range due to environmental interference.

• Self-healing The network is self-healing, which means that when a relaying MicroRouter fails, alternative paths are used to deliver data at the destination.

• Energy-efficient The network is energy-efficient. MicroRouters maximize their sleep time -and therefore increase battery lifetime - by communicating only at certain highly synchronized time intervals.

Ambient Protocol Stack

Ambient’s Product Series 3000 is based on the IEEE 802.15.4 standard. This standard is designed for low-cost communication between physical objects and devices (in contrast with more user-oriented networks, such as Wi-Fi). IEEE 802.15.4 is not a complete network protocol stack, and only provides the lower level network layers (in the OSI reference model the physical layer and the medium access layer). As defined in the IEEE 802.15.4 standard, the Ambient Product Series 3000 operates in the globally available 2.44 GHz bandwidth. The Ambient protocol stack includes a number of additional protocols, which were specifically designed to meet the requirements from transport & logistics applications.

Some of the important protocols are described below:

• Reliable Transport Protocol (RTP) – The Reliable Transport Protocol is an optional mechanism that notifies the sender of data whether that data is actually received by the destination, also in multi hop communication. The protocol is able to setup a streaming connection. A connection between source and destination is setup and the source can continuously stream messages through this connection reliably until it has no more data to send.

• Remote Update Protocol (RUP): The Remote Update Protocol runs in parallel to the routing and transport protocols. It is used to communicate a large amount of data throughout the network to each node. It can be used to perform a system-wide firmware upgrade. The transferred data is the new firmware image and every MicroRouter receiving it can use it to reprogram itself.

• Device Driver Interface (DDI): The Device Driver Interface allows users, applications and nodes to access resources in a standardized manner. Resources are made accessible by implementing drivers for them. Using DDI, it is possible to access these drivers and, in that way, obtain information from them or send information to them. The latter might be the case when a driver needs to be configured.