Teemupekka Virtanen

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— Java 2 Micro Edition (J2ME) is a runtime environment for resource-constrained environments. There are already millions of J2ME enabled mobile devices that support the first version of the Mobile Information Device Profile (MIDP) in J2ME. Many security threats exist in MIDP 1.0 environment since the specification addresses only a limited number of security(More)
Ad hoc networks are new paradigm of networks offering unrestricted mobility without any underlying infrastructure. The ad hoc networks have salient characteristics that are totally different from conventional networks. These cause extra challenges on security. In an ad hoc network, each node should not trust any peer. However, traditional cryptographic(More)
Predictable initialization vectors in IPsec ESP encryption, allowed by the IPsec specifications and used by most implementations, compromise IPsec confidentiality. By using an adaptive chosen plaintext attack, an attacker can break low entropy plaintext blocks using brute force, and confirm guesses of the contents of arbitrary plaintext blocks. We analyze(More)
Medical research requires information. Now this information is collected from various sources and the quality of information is often poor because of different coding and collection methods. In Finland we are now building the national archive to store all the patient information from both public and private service providers. We have started to design a(More)