Peltier-elementin jänniteohjaus

Opinnäytetyön aiheena oli työstää jännitteenohjauksen kytkennät Peltier-elementille. Toteutuksen täytyi olla mahdollisimman yhteensopiva eri piirisarjojen kanssa, jotta kytkentöihin ei tarvitsisi tehdä suuria muutoksia. Työssä pyritään pääsemään mahdollisimman vähäisillä komponenttimäärillä. Työssä kerrottaan eri kytkentävaihtoehdoista ja todetaan, miksi päädyttiin kyseiseen kytkentään. Opinnäytetyössä kertotaan myös lyhyesti, miten muut kytkentävaihtoehdot eroavat työssä käytetystä kytkennästä. Opinnäytetyn pohjana on Peltier-elementti, ja työssä kerrotaan sen käytön syistä. Erityistä huomiota kiinnitettiin Peltier-elementin tehon tarpeeseen. Esimerkkeinä käytetään Atmelin ja Microchipin kontrollereita ja arvioidaan, kuinka hyvin ne sopivat yhteen kytkennän kanssa. Kerrotaan myös, kuinka kytkentää olisi tarvittaessa muutettava yhteensopivuuden ylläpitämiseksi. Työ onnistui kokonaisuutena kiitettävän hyvin ja laite tuli ajamaan sille tarkoitettua asiaa. Laite kokonaisuutena ei kuitenkaan ole täydellinen, vaan siitä löytyy kohtia joita voisi parantaa.The objective of this thesis was to make voltage control for a Peltier element. Implementation must be as compatible with different chipsets as possible, so that major changes would not need to be made to the connections. The aim was to reach a minimum number of components. The thesis tells about different connection solutions and explains why this particular connection was chosen. There is a brief explanation how the other connection options differed from the connection option chosen here. The basis of this thesis was a Peltier element; The reasons for choosing the P.e. are explained. The power consumption of pelrier element is also paid attention to. Compatibility was evaluated with Atmel and Microchip controllers. It is also explained how the connection should be modified, if necessary, to maintain compatibility

BLIND: A complete identity protection framework for end-points

In this paper, we present a security framework that provides identity protection against active and passive attacks for end-points. The framework is based on a two-round-trip authenticated Diffie-Hellman key exchange protocol that identifies the end-points to each other and creates a security association between the peers. The protocol hides the public key based identifiers from attackers and eavesdroppers by blinding the identifiers. We complete the identity protection by offering location privacy with forwarding agents. To our knowledge, our privacy enhanced protocol is the first denial-of-service resistant two-round-trip key exchange protocol that offers identity protection for both communicating peers

Rethinking security in IP based micro-mobility

Security problems in micro-mobility are mostly related to trust establishment between mobile nodes and middle-boxes, i.e. mobile anchor points. In this paper, we present a secure micro-mobility architecture that scales well between administrative domains, which are already using different kind of network access authentication techniques. The trust between the mobile nodes and middle boxes is established using one-way hash chains and a technique known as secret splitting. Our protocol protects the middle-boxes from traffic re-direction and related Denial-of-Service attacks. The hierarchical scheme supports signaling optimization and secure fast hand-offs. The implementation and simulation results are based on an enhanced version of Host Identity Protocol (HIP). To our knowledge, our micro-mobility protocol is the first one-and-half round-trip protocol that establishes simultaneously a trust relationship between a mobile node and an anchor point, and updates address bindings at the anchor point and at a peer node in a secure way

End-point identifiers in secure multi-homed mobility

Currently IP addresses are used both for node identifiers and topological location names in the Internet. The semantic overloading and non-cryptographic nature of IP addresses makes it impossible to use them as identifiers from the security point of view. The problem becomes even worse with multi-homed mobile nodes. Multi-homed mobile nodes have several interfaces bound to dynamically changing IP addresses. When a node changes its point of attachment to the network or it reroutes traffic fromone interface to another, the connection identifiers are changed. A peer node cannot verify the validity of the new identifiers without a naming trust relationship between the identifiers and the identity of the node. The peer must have evidence that an identifier belongs to a specific identity. Currently, there are no way for a node, using traditional IP addresses, to prove that it owns a specific address, i.e., an identifier. We present in this paper the philosophy behind separation of end-point identifiers from location names, which is an essential part in designing secure multi-homed mobility architectures

Host identity protocol: Achieving IPv4 - IPv6 handovers without tunneling

In the current Internet, hosts are identified using IP addresses that depend on their topological location. In other words, the IP addresses are semantically overloaded since they identify both hosts and topological locations. The Host Identity Protocol (HIP) introduces a way of separating the location and host identity information. It introduces a new namespace, cryptographic in nature, for host identities. The IP addresses continue to be used for packet routing. In this paper we describe how HIP can be used to implement mobility and multi-address multihoming across the two versions of IP, IPv4 and IPv6

A Time-Variant MIMO Channel Model Directly Parametrised from Measurements

... channel model that is directly parametrised from measurements. Using a fully automated algorithm, multipath clusters are identified from measurement data without user intervention. The cluster parameters are then used to define the propagation environment in the RCM. In this way, the RCM provides a direct link between MIMO channel measurements and MIMO channel modelling. For validation, we take state-of-the-art MIMO measurements, and parametrise the RCM exemplarly. Using three different validation metrics, namely, mutual information, channel diversity, and the novel Environment Characterisation Metric, we find that the RCM is able to reflect the measured environment remarkably well. Copyright © 2009 Nicolai Czink et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited