Nec Corporation

Nec Europe Ltd.

Dirk Westhoff

Joao Girao

Frederik Armknecht

Bernd Lamparter

Mithun Puthige Acharya

Einar Mykletun

A method for managing data in a preferably non real-time sensor network, wherein the network comprises a multitude of sensor nodes to sense data, wherein the network is divided into clusters with each consisting of several sensor nodes, wherein within each cluster a sensor node acts as aggregator node to aggregate the sensed data of the rest of the sensor nodes of the cluster, and wherein always a pre-configurable number of neighbored clusters are combined to groups and the data aggregated within a cluster are stored by the aggregator node of the cluster itself and in addition by another aggregator node of a cluster of the respective group is characterized in that the data is encrypted with homomorphic methods before being stored persistently.

Method for managing data in a wireless sensor network

A method for aggregating data in a network, particularly in a wireless sensor network, wherein the network () includes a plurality of sensor nodes (N) to measure data and at least one sink node (S) at which the data measured by the sensor nodes (N) are aggregated, and wherein each sensor node (N) encrypts its measured data with a key k and forwards the result towards the sink node (S), is characterized in that, in the context of a key distribution within the network (), a master key K is chosen, and that the master key K is autonomously split up by the network () into individual keys kto be used by the sensor nodes (N) for encrypting measured data, with the sum of all individual keys kbeing equal to the master key K.

Method for aggregating data in a network

A method for authentication of elements of a group, especially for authentication of sensor nodes in a preferably wireless sensor network is disclosed. The group has one specific element&#x2014;leading element&#x2014;with which each of the group elements can exchange information and wherein the authentication of the group elements takes place with regard to the leading element. The leading element sends an authentication request to the group elements wherein the authentication request is the same for all the group elements. The group elements each send authentication responses&#x2014;based on the authentication request&#x2014;to the leading element, with the authentication responses being different for each group element.

Method for authentication of elements of a group

A method for electing aggregator nodes in a network, wherein the network includes a plurality of sensor nodes to measure data, and at least one of the sensor nodes functioning as aggregator node to aggregate sensored data obtained by at least a subset of the sensor nodes, the network further including at least one sink node to collect data aggregated by the aggregator nodes, the method including: establishing pairwise secret keys between a current aggregator node and each sensor node of the subset of sensor nodes; at each of the sensor nodes of the subset, choosing a random number and encrypting the random number using the established key; providing a communication chain between the sensor nodes of the subset and summing the encrypted random numbers of all sensor nodes of the subset; and determining a new aggregator node on the basis of the resulting sum according to a predefined calculation scheme.

Method for electing aggregator nodes in a network

In a method for distributing keys for encrypted data transmission in a sensor network, nodes store a subset of keys from a set of keys. A sink node triggers the key election procedure and sensor nodes choose from a locally broadcasted keyID list, with one key to be stored on each node. All other initially stored keys are subsequently deleted. The process is repeated until the edge of the network is reached. Such key predistribution is suitable for the encryption of reverse multicast traffic to the sink node which is the predominant traffic pattern in wireless sensor networks.

Method for distributing keys for encrypted data transmission in a preferably wireless sensor network

Method to transmit data in an ad hoc network or a sensor network with the network comprising a multitude of sensor nodes to sensor data, at least one aggregator node to aggregate the sensored data of at least a subset of the sensor nodes, and at least one sink node to collect the data of the aggregator node is characterized in&#x2014;regarding a high level of security against attacks from outside while transmitting data, and regarding an economic energy consumption&#x2014;that the sensored data is encrypted at the sensor nodes, that the encrypted data is transmitted to one of the aggregator nodes, that at the aggregator node an aggregation function is executed on the encrypted data, and that the result of the aggregation function is transmitted to the sink node and decrypted there.

Method of transmitting data in a network

A technique to transmit data from a sender to a receiver via a network, preferably a LAN and/or the Internet etc., where the sender transmits the data to a base station, and where the sender is verified by a server, in particular a AAA-server etc. In order to prevent the transmission of data from an illegitimate sender at the expense of a legitimate sender to the greatest extent possible, the server transmits verification data from the server to the sender and/or base station.

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Heidelberg, Germany

Dirk Westhoff