Access Point

An access control system has the role to verify and mediate attempts made by users to access resources in a system. An access control system maps activities and resources to legitimate users. This paper presents a distributed smart card based access control system for a building. The system is Internet centered. Each door has a control access point and all these are connected to a server which will grant or not the access. A user requests access by using a smart card which memorizes the user's unique identity code.

The widespread proliferation of wireless networks (WLAN) has opened up new paradigms of security policy management in enterprise networks. To enforce the organizational security policies in wireless local area networks (WLANs), it is required to protect the network resources from unauthorized access. In WLAN security policy management, the standard IP based access control mechanisms are not sufficient to meet the organizational requirements due to its dynamic topology characteristics. In such dynamic network environments, the role-based access control (RBAC) mechanisms can be deployed to strengthen the security perimeter over the network resources. Further, there is a need to incorporate time and location dependent constraints in the access control models. In this paper, we propose a WLAN security management system which supports a spatio-temporal RBAC (STRBAC) model. The system stems from logical partitioning of the WLAN topology into various security policy zones. It includes a Global Policy Server (GPS) that formalizes the organizational access policies and determines the high level policy configurations for different policy zones; a Central Authentication & Role Server (CARS) which authenticates the users (or nodes) and the access points (AP) in various zones and also assigns appropriate roles to the users. Each policy zone consists of an Wireless Policy Zone Controller (WPZCon) that co-ordinates with a dedicated Local Role Server (LRS) to extract the low level access configurations corresponding to the zone access points. We also propose a formal spatio-temporal RBAC (STRBAC) model to represent the security policies formally.

A VLAN is a logical connection that allows hosts to be grouped together in the same broadcast domain, so that packets are delivered only to ports that are combined to the same VLAN. We can improve wireless network performance and save bandwidth through the characteristic VLAN network. In addition, the implementation of VLAN greatly improves wireless network security by reducing the number of hosts receiving copies of frames broadcast by switches, thus keeping hosts holding critical data on a separate VLAN. In this paper we compare wireless network with VLAN via wireless network. The proposed network is evaluated within terms of delay and average throughput using web browsing applications and file transfer in heavy traffic. The simulation was carried out using OPNET 14.5 modeler and the results show that the use of VLAN via wireless network improved performance by reducing traffic resulting in a minimized delay time. Furthermore, VLAN implementation reduces network throughput because...

... 5: Scalable Video Coding (in integrated form with ITU-T Rec. H.264 | ISO/IEC 14996-10). JointVideo Team (JVT), Doc. JVT-R201, Jan. 2006. 4. Luby, M., Stockhammer, T., Watson, M., Gasiba, T., and Xu, W. Raptor Codes for Reliable Download Delivery in Wireless Broadcast ...

Access Point mode adalah salah satu konfigurasi yang paling banyak dilakukan. Karena dengan mode ini kita bisa sharing koneksi internet yang kita miliki ke tempat yang lebih jauh. Hal ini sangat cocok digunakan untuk warung kopi, kafe atau bisnis apapun yang memiliki area luas dan client sangat banyak

Some plants hyperaccumulate metals or metalloids to levels several orders of magnitude higher than other species. This intriguing phenomenon has received considerable attention in the past decade. While research has mostly focused on the above-ground organs, roots are the sole access point to below-ground trace elements and as such they play a vital role in hyperaccumulation. Here we highlight the role of the root as an effective trace element scavenger through interactions in the rhizosphere. We found that less than 10% of the known hyperaccumulator species have had their rhizospheres examined. When studied, researchers have focused on root physical characteristics, rhizosphere chemistry, and rhizosphere microbiology as central themes to understand plant hyperaccumulation. One physical characteristic often assumed about hyperaccumulators is that their roots are small, but this is not true for all species and many species remain unexamined. Transporters in root membranes provide avenues for root uptake, while root growth and morphology influence plant access to trace elements in the rhizosphere. Some hyperaccumulators exhibit unique root scavenging and direct their growth toward elements in soil. Studies on hyperaccumulator rhizosphere chemistry have examined the role of the root in altering elemental solubility through exudation and pH changes. Different interpretations have been reported for mobilization of non-labile trace element pools by hyperaccumulators. However, there is a lack of evidence for a novel role for rhizosphere acidification in hyperaccumulation. As for microbiological studies, researchers have shown that bacteria and fungi in the hyperaccumulator rhizosphere may exhibit increased metal tolerance, act as plant growth promoting microorganisms, alter elemental solubility, and have significant effects on plant trace element concentrations. New evidence suggests that symbiosis with arbuscular mycorrhizae may not be rare in hyperaccumulator taxa, even in some members of the Brassicaceae. Although there are several reports on the presence of mycorrhizae, a cohesive interpretation of their role in hyperaccumulation remains elusive. In summary, we present the current state of knowledge about how roots hyperaccumulate and we suggest ways in which this knowledge can be applied and improved.

There is currently a strong focus worldwide on the potential of large-scale Electronic Health Record systems to cut costs and improve patient outcomes through increased e-ciency. A number of countries are developing nationwide EHR systems to aggregate services currently pro- vided by isolated Electronic Medical Record databases. However, such aggregation introduces new risks for patient privacy and data security, both