Mandatory access control models have traditionally been employed as a robust security mechanism in multilevel security environments such as military domains. In traditional mandatory models, the security classes associated with entities are context-insensitive. However, context-sensitivity of security classes and flexibility of access control mechanisms may be required especially in pervasive c...

The paper proposes a method based on different security-related factors to dynamically calculate the validity period of digital certificates. Currently validity periods are most often defined statically without scientific justification. This approach is not sufficient to objectively consider the actual need for security. Therefore the approach proposed in this paper considers relevant security ...

Masking is a widely used countermeasure to protect block cipher implementations against side-channel attacks. The principle is to split every sensitive intermediate variable occurring in the computation into d + 1 shares, where d is called the masking order and plays the role of a security parameter. A masked implementation is then said to achieve d-order security if any set of d (or less) inte...

One of the most important protocols for implementing tunnels in order to take action of secure virtual private network is IPsec protocol. IPsec policies are used widely in order to limit access to information in security gateways or firewalls. The security treatment, namely (Deny, Allow or Encrypt) is done for outbound as well as inbound traffic by security policies. It is so important that the...

In today’s world, IT security plays a critical role in different organizations, yet little is known about IT security in the context of organizations. This paper addresses this issue based on qualitative description analysis of 10 interviews with IT security practitioners from small to medium size organizations. Our results revealed the required knowledge and skills for effective IT security, I...

An eternal $m$-secure set of a graph $G = (V,E)$ is aset $S_0subseteq V$ that can defend against any sequence ofsingle-vertex attacks by means of multiple-guard shifts along theedges of $G$. A suitable placement of the guards is called aneternal $m$-secure set. The eternal $m$-security number$sigma_m(G)$ is the minimum cardinality among all eternal$m$-secure sets in $G$. An edge $uvin E(G)$ is ...