Computer security

Abstract

Computer security encompasses concepts and methods for protecting sensitive resources in computer systems. Computer security starts from the policies that regulate access to protected resources. In technology, the focus is on mechanisms for enforcing these policies. We will put various enforcement mechanisms into context with the policies and the IT architectures they were originally designed for. We will also briefly touch on network security and conclude with remarks on security evaluation. Copyright © 2010 John Wiley & Sons, Inc. This article is categorized under: Algorithms and Computational Methods > Networks and Security

Contingency Revisited: Secure Construction and Legal Implications of Verifiably Weak Integrity

“…Gollmann's computer security textbook acknowledges from the first edition in 1999 that it is "not easy to give a concise definition" [15] of integrity. Other definitions of integrity allow to differentiate between authorized and unauthorized modifications.…”

“…Other definitions of integrity allow to differentiate between authorized and unauthorized modifications. [15] We do not want to do another hunt for an integrity definition. For this paper it is sufficient to see integrity as a state describing data which is verifiably to be "as it was supposed to be" [15] since the integrity protection was applied.…”

“…We define it as follows: Definition 1 (Integrity:). Integrity describes the verifiable state that data "is as it is supposed to be" [15] since the integrity protection was applied. The applied integrity protection mechanism intrinsically defines which actions will make the verification of integrity return a negative result.…”

Non-repudiation Analysis with LySa

“…This is done using evidences [9] that allow to decide unquestionably in favor of the fair principal whenever there is a dispute. In particular, non-repudiation of origin provides the recipient with proof of origin while non-repudiation of receipt provides the originator with proof of receipt.…”

From Weak to Strong Watermarking

“…Given this history, it is not surprising that in the security community, there is a perception that secure watermarking is "theoretically impossible," as expressed, for instance, in [1,17,18]. While this idea is intuitively appealing, it is difficult to prove something is (im)possible without first formally defining the notion.…”