Due to proliferation of diverse network applications, DoS/DDoS attacks are evolving. Many studies have been performed and implemented in on/off-line network devices such as routers and IDS/IPS. While IDS/IPS is powerful enough to handle deep packet inspection (DPI) tasks, routers are better suited in real-time and line-speed processing requirements. Since the routers are designed to handle IP packet header information, if one can devise an DoS/DDoS detection/prevention methods that utilizes the router specific features it will be best for the in-line and real-time processing. We introduce a Flow based DoS/DDoS detection algorithm(FDDA) that detects Distributed Denial of Service (DDoS) attacks by monitoring TTL and ID fields of incoming packet's IP header. As DDoS attacks are based on IP source address spoofing, the TTL and ID fields may have abnormal behavior. The device keeps track of 8-tuple flow table. The behavior of these two fields is monitored to determine DoS/DDoS attack situation. The effectiveness of our method is such that it is implemented flow-based routers and devices.

In this paper, we describe a package delivery problem and propose a method based on the Extended Simulated Annealing(ESA) algorithm which is able to find an optimal routing path for efficient package delivery service. The problem domain that we solve is modeled as a weighted, directed graph.

Current studies on Digital Rights Management (DRM) have focused on security and encryption as a means of solving the issue of illegal copying by purchasers. In this paper, we propose an end-to-end key management scheme that can cover a content protection on the overall value-chains of content distribution. The proposed scheme can protect digital content from attacks since an encrypted content is sent by a first package server and only DRM client can decrypt the encrypted digital content. It makes it possible to protect content from content creator to purchaser.

During handover between heterogeneous networks such as the 3G mobile telecommunication systems and the Wireless LAN systems, a subscriber authentication, the Mobile IP operations for IP mobility and an accessing to a data gateway are heavy burdens due to its time-taken operations and overheads. So they are main factors of handover delays. This paper proposes the handover strategies for reducing handover delays in the UMTS (Universal Mobile Telecommunications System) and the Wireless LAN overlay networks. For decreasing the delays, mandatory use of a fast re-authentication is applied and newly added features of one for the UMTS are introduced. And simplified MIPv6 operations and an optimized gateway approach to minimize the network access time are proposed. These proposed approaches are analyzed and evaluated with the results of an authentication test bed and a network simulation.

By mutual complemented reason of wide coverage and high data transmission, the integration and handover of SG network and WLAN is regarded as an important function for 3G beyond (B3G) mobile communication systems. The seamless mobility is one of the basic requirements for handover between these heterogeneous networks. In this paper, we present a seamless handover mechanism for UMTS and WLAN within the framework of handover architecture, IP mobility and authentication mechanism. Firstly, we review the 3GPP-specific integration architecture of UMTS and WLAN, WLAN UE-initiated tunnel mechanism, IP mobility and authentication mechanisms of both networks. Then we propose the configuration of mobile IPv6 based UMTS-WLAN overlay network and the security mechanism for reducing the handover delay. Lastly we show the operation of seamless handover in our proposed network model.