Content Aware Smart Routing
|Wolfgang Kastner , Günther Gridling
Today's Internet has reached its scalability limits with respect to the number of participants and performance. Contemporary Internet devices are not just computers, but also tablets, smart phones and even small devices, like sensors and actuators. A variety of new technologies is inherent to these Internet appliances, like IPv6, ZigBee, 6LoWPAN, NFC or RFID. From the combination of these technologies a new paradigm arises, the so called Internet of Things (IoT). The problem of all these new services is how a service can be addressed. Typically, a client has to know the exact URI in order to use a specific service hosted by a server somewhere in the Internet. This thesis provides a concept which relaxes the strong binding between service and server by the use of IPv6 focusing on the addressing of sensors and actuators. A client can place an unaddressed request to the so called content aware network. A special router, called smart router, fetches the request and forwards it to a dedicated server which is able to process the request. To this end, the request contains a semantic tag which is interpretable by participating network nodes. In order to determine the correct address of a server, the smart router inquires a resolver. This resolver uses a semantic reasoner utilizing a smart routing ontology in order to augment the request by known facts. The resolver converts the request to a more specific query for a domain server. There can be several domain servers for a variety of domains. After the initial primary request is sent to its target server, this server examines the request and performs one or more secondary requests in order to set the corresponding actuators or to fetch current values from sensors. This secondary request is also unaddressed and forwarded to the correct network nodes by use of the inherent knowledge of the content aware network. In addition to the correct routing of unaddressed client requests, the content aware network approach is also able to route unaddressed data packets sent from sensor/actuator-units. Such a data packet can be sent for example on the change of a node-s internal state (e.g. on the exceeding of certain thresholds). As a proof of concept, an elementary reference system is implemented. This implementation provides a reduced set of functionalities in order to evaluate the concept with respect to performance, security and fault tolerance. The content aware network-s performance, measured in the amount of messages, is compared to some theoretical alternative approaches. In order to preserve security, IPsec is investigated.