Roxana Zoican

Analysis of Scalability in MANET's Protocols

Ad-hoc networks enable spontaneous connectivity among wireless devices, without requiring any particular infrastructure. At present, the increasing demand is towards applications like scientific exploration, online gaming with multiple players, law enforcement, personal communication, etc. In all these applications, group communication is more important. Multicasting provides necessary services for group communication in such type of applications. With the increasing number of nodes, scalability issue in multicasting of mobile ad hoc network is still an open problem.

Analysis and simulation of a Predictable Routing Protocol for VANETs

Vehicular ad hoc networks (VANETs) are expected to support a large spectrum of mobile distributed applications ranging from traffic alert dissemination and dynamic route planning to context-aware advertisement and file sharing. Internetworking over VANETs becomes one of the most important applications and desired service for mobile users. In current ad-hoc routing protocols, the control messages in reactive protocols and route update timers in proactive protocols are not used to anticipate link breakage. They only indicate presence or absence of a route to a given node. Consequently, the route maintenance process at both protocol types is initiated only after a link breakage event takes place. This paper analysis the possibility to predict a link breakage event prior to its occurrence. Vehicles are grouped according to their velocity vectors. When a vehicle shifts to a different group and a route, involving the vehicle, is to be broken, the protocol searches for a more stable route that includes vehicles from the same group. Whilst this scheme (Predictable Routing Protocol - PRP) can be implemented on any existing routing protocol, the paper considers the case of PRP over Destination-Sequenced Distance Vector (DSDV) routing protocol and Optimized Link State Routing (OLSR) protocol. The performance of the scheme is evaluated through computer simulations.

An Enhanced Performance Clustering Algorithm for MANET

Clustering of mobile nodes among separate domains has been proposed as an efficient approach to mimic the operation of the fixed infrastructure and manage the resources in multi-hop networks. In this paper, it was analyzed a weight-based clustering algorithm. This algorithm is called Enhanced Performance Clustering Algorithm (EPCA). It selects clusterhead according to its weight computed by combining a set of system parameters and defines new mechanisms as cluster division, merging diminution and extension. EPCA was simulated and tested in real conditions in a campus environment.

Lane departure warning system implementation using the Blackfin microcomputer

the purpose of this paper is to evaluate the performance of an embedded lane departure monitoring system implemented using the Blackfin microcomputer. This paper is focused on evaluating the image processing algorithm and the main goal of this work is to propose methods to speed-up the necessary computations. A practical, flexible and low cost solution is proposed and the monitoring system is effective at medium vehicle speeds.

Flat routing protocols for ad hoc mobile wireless networks

Ad hoc networks are characterized by multihop wireless connectivity, frequently changing network topology and the need for efficient dynamic routing protocols plays an important role. In these networks there is no fixed topology due to the mobility of nodes, interference, multipath propagation and path loss. Hence a dynamic routing protocol is needed for these networks to function properly. Many of them have been developed for accomplishing this task. This paper presents two mobile ad-hoc routing protocols DSDV and AODV where the first one is a proactive protocol depending on routing tables which are maintained at each node. The other one is a reactive protocol, which finds a route to a destination on demand, whenever communication is needed.

A frequency planning analysis of a two-tier microcell/macrocell cellular system

We analyse a systematic way of finding an optimal partition of frequency spectrum in a two-tier microcell/macrocell cellular system. To keep the handoff rate in this two-tier cellular system at an acceptable level, low mobility users (v<Vo) should undergo handoffs at microcell boundaries and high mobility users (v>Vo) should undergo handoffs at macrocell boundaries. The probability of erroneous assignment of a mobile to a microcell or macrocell is significantly lower than previous approaches. We analyze the optimal velocity threshold Vo and propose a dynamically adjusting method according to traffic load.

Face Detection in Internet of Things Using Blackfin Microcomputers Family

This paper describes a face detection system based on the Blackfin microcomputer architecture that may be used in an Internet of Things (IoT) context. The face detection algorithm is based on skin detection and scanning binary images to determine the face area. Further image processing may determine the eyes and mouth in order to extract main face characteristics. The face detection algorithm may be used in context of IoT to determine the searching area for eyes and mouth (e.g. for face recognition and emotion detection). The face detection algorithm is implemented using the Visual DSP++ integrated development environment and face detection is achieved in real time.

Improved load balancing and scheduling performance in embedded systems with task migration

This paper presents a migration mechanism for tasks running in nodes of a wireless sensor network (WSN). The WSN is consisted of digital signal processing nodes implemented with Blackfin microcomputers with Micrium μC OS III operating system. The migration mechanism allows load balancing, better scheduling of the tasks and allow cooperative signal processing at the whole network and it is useful in case of the node failures as well. This mechanism uses the Micrium operating system primitives in order to decide when the task migration will be started and to control the whole migration process. The communication network is provided by Lightweight Internet Protocol (LwIP) protocol. A performance evaluation (load balance, migration time and missed deadlines ratio) is performed. The paper demonstrates viable implementation of tasks migration in embedded systems and illustrates a better performance of the load balancing and the tasks scheduling.

Embedded content aware router implementation using the Blackfin microcomputer

The purpose of this paper is to evaluate the performance of embedded content aware routers implemented using the Blackfin microcomputer. The main goal of this work is to propose methods to speed-up the necessary computations in the content aware routers. A practical solution is proposed.

Implementation and evaluation of a Multilevel-Clustering Routing Algorithm for MANETs

Mobile ad hoc networks (MANETs) are autonomously self-organized networks without infrastructure support. In a mobile ad hoc network, nodes move arbitrarily; therefore the network may experience rapid and unpredictable topology changes. Because nodes in a MANET normally have limited transmission ranges, some nodes cannot communicate directly with each other. Hence, routing paths in mobile ad hoc networks potentially contain multiple hops, and every node in mobile ad hoc networks has the responsibility to act as a router. In this article it is examined the importance of wireless ad-hoc networks and the Multilevel-Clustering Routing Algorithm (MCRA). The MCRA algorithm was simulated with our MANSIM simulator and then it was fully implemented in a real-world environment (the campus of the University Politehnica of Bucharest (UPB)). The results demonstrate that, among other MANET routing protocols, the performances of the MCRA protocol are highly improved.