Title	Hybrid adaptation of the maximum contention window (CWmax) and minimum contention window (CWmin) for Enhanced Service Differentiation in IEEE 802.11 Wireless Ad-hoc Networks
Author	Hassan Takabi, Ali H. Moghadam, Ahmad Khonsari
Citation	Vol. 6  No. 12  pp. 281-290
Keywords	IEEE 802.11e, QoS, EDCA, back-off algorithm, wireless ad-hoc networks, hybrid adaptation algorithm, CWmax, CWmin

Title	Interoperability Mechanisms for Registration and Authentication on Different Open DRM Platforms
Author	Carlos Serr?o, Victor Torres, Jaime Delgado, Miguel Dias
Citation	Vol. 6  No. 12  pp. 291-303
Keywords	DRM, interoperability, security, registration, authentication

Title	A Model-Oriented Dynamic Architecture and Its Supporting System
Author	Yang He-biao, Zhang Jian-ming, Zhan Yong-zhao
Citation	Vol. 6  No. 12  pp. 304-310
Keywords	Model, Software architecture, Dynamic evolution, Framework

Title	Vulnerability Analysis through a Graph-based Protection System
Author	Mohammad Ebrahim Rafiei, Rasool Jalili, Hamid Mousavi
Citation	Vol. 6  No. 12  pp. 311-319
Keywords	Vulnerability Analysis, Protection System, Safety Problem, NP-Completeness.