A cooperative mobile throwbox-based routing protocol for social-aware delay tolerant networks

Wireless Networks - In delay tolerant networks (DTNs), nodes have intermittent connectivity patterns due to various factors such as mobility, sparse network topology, and unpredictable movement...     

Neighbors’ interference situation-aware power control scheme for dense 5G mobile communication system

The next generation mobile communication (5G) systems is targeting very high data rate by deploying more number of small cells, but this deployment results in high cross-tier interference because of using the same frequency band. To solve this challenge, an efficient power control scheme is desired specially for the case of uplink scenario. Thus, to solve this challenge, we propose the neighbors’ interference situation-aware uplink power control (IA-ULPC) scheme to reduce the cross-tier interference. In this scheme, we consider the interference situation of the neighbor cells while controlling the power of the users. Moreover, we also derive the target signal-to-interference and noise-ratio (\(P_0\)) equation to dynamically adjust it based on the neighbors’ base station interference situation. We compare the performance of the proposed IA-ULPC with the conventional fractional power control scheme (C-FPC). The extensive system-level simulations are carried out to prove the validity of the proposed IA-ULPC scheme which almost doubles the user average throughput and also decreases the interference around 20% in dense two-tier heterogeneous network environment as compared to C-FPC.     

Remaining idle time aware intelligent channel bonding schemes for cognitive radio sensor networks

Wireless Networks - Channel bonding (CB) is a technique used to provide larger bandwidth to users. It has been applied to various networks such as wireless local area networks, wireless sensor...     

Pricing strategies and categories for LTE networks

Long Term Evolution (LTE) systems will provide a large number of users with various high quality wireless Internet services including but not limited to voice over IP, real-time gaming, multimedia streaming and several others. A suitable pricing policy is an important component in order to bring benefits to both the operators and the customers. In fact, through this, the operator can efficiently manage the radio resources of cellular networks. For different types of services, the operator can maintain user Quality of Service and through which, the revenue can be optimized. This article analyzes various possible LTE pricing schemes, including the one proposed, based on different criteria: network load and congestion, operator revenue, traffic differentiation and user categorization. We provide comparative graphs to highlight the pros and cons of the studied pricing strategies. We highlight the importance for the operator to move from the often used flat-rate style policies towards more dynamic pricing strategies taking into account the user and service classes.     

ZGLS: a novel flat quorum-based and reliable location management protocol for VANETs

In location management services, a destination advertises its position attributes to a set of vehicles called location servers while, a source obtains these attributes from such location servers to track destination. The location management techniques in VANET have been categorized into flooding-based, flat hashing-based, hierarchical hashing-based and hierarchical quorum-based techniques. In flooding-based location service, destination information is flooded to the entire network which results into high congestion, low throughput and non-scalable network. In flat hashing, a global hash function is applied to compute location servers of each destination which results into higher delay, drop and signaling overhead in large VANETs. In hierarchical hashing, global hash function computes location servers of destination in hierarchical order. It therefore suffers from handover signaling between servers, high load on the top hierarchy and location query delay when source and destination are apart. In hierarchical quorum-based, location servers are identified cluster-wise and therefore it also suffers from the problems similar to hierarchical techniques. To overcome these problems, ZoomOut Geographic Location Service (ZGLS) protocol is proposed which introduces flat quorum-based location management service. In contrast to the aforementioned techniques, the novelty of ZGLS lies in the fact that it has shifted the location server role from hashing-based or clustering-based geographic areas to few 1-hop neighbours, called relatives. The proposed protocol creates a chain of relatives to provide positioning and tracking service. To evaluate signalling overhead, timeliness and the reliability of update and query packets, ZGLS is compared with RLSMP and HRHLS through ns-2 simulations. The results reveal that ZGLS stands out as a better choice for large-scale sparse and dense VANETs.     

Performance evaluation of broadcasting strategies in cognitive radio networks

Broadcasting is an important phenomenon, because it serves as simplest mode of communication in a network, via which each node disseminates information to their neighboring nodes simultaneously. Broadcasting is widely used in various kind of networks, such as wireless sensor networks, wireless networks, and ad-hoc networks. Similarly, in cognitive radio networks (CRNs), broadcasting is also used to perform many tasks including neighbor discovery, spectrum mobility, spectrum sharing, and dissemination of message throughout the network. The traditional approach that has been used as broadcasting in CRNs is simple flooding in which a message is disseminated in the network without any strategy check. Simple flooding can cause major setbacks in the network, such as excessive redundant rebroadcasts, and collision drops which collectively are termed as broadcast storm problem. To reduce the effects of broadcast storm problem in wireless networks, we propose and compare four broadcasting strategies for cognitive radio networks in this paper. These four strategies are: (1) probability based, (2) counter based, (3) distance based, and (4) area based. Extensive NS-2 based simulations are carried out on different threshold values for each broadcasting strategy. After experimental evaluation, it is demonstrated that counter based broadcasting surpasses other broadcasting strategies by achieving maximum delivery ratio of 60% and by decreasing redundant rebroadcasts and collision drops up to 44 and 37% respectively.

     

The role of the enterprise architect

The emergence of enterprise architecture (EA) as a mechanism for addressing increased complexity has resulted in a newly evolving profession of enterprise architect. This paper summarizes the results of a study that explored the role of the enterprise architect as viewed by subject matter experts within the executive branch of the US Federal Government. The results of the research study identified several functional roles of the enterprise architect and described the interfaces with other functional roles. The study determined the unique value that the role provides to the enterprise and the impact of not filling this role. The study examined the optimal organizational positioning and the competencies needed to maximize effectiveness in the role. The insights gained from this study are the first step in defining the role of the enterprise architect. This theory forms the foundation needed to support a recognized profession of enterprise architect and provides several recommendations for further research.