Embracing Interference in Ad Hoc Networks Using Joint Routing and Scheduling with Multiple Packet Reception

We present an approach that takes advantage of multi-packet reception (MPR) to reduce the negative effects of multiple access interference and therefore increase the capacity of an ad hoc network. We analyze the performance upper bound of joint routing and scheduling for ad hoc networks that embrace interference by using MPR. We formulate the optimization problem under a deterministic model and seek to maximize the aggregate network throughput subject to minimum rate requirements. We then propose a polynomial-time heuristic algorithm aimed at approximating the optimal solution to the joint routing and channel access problem under MPR. We show the effectiveness of our heuristic algorithm by comparing its performance with the upper bound.

Minimizing interference of a wireless ad-hoc network in a plane

The year 2005 witnesses the third occasion that the Wireless Personal Area and Ad-hoc Networks minitrack is part of the annual HICSS conference. This year there was a substantial increase in submissions (thus a substantial decrease in the acceptance rate), indicating the growing importance of research in this area. The minitrack is also focused on fundamental challenges and issues arising in wireless sensor networks and their applications. Wireless sensor networks differ from other wireless networks in the need for unattended and very low-energy operation, in the possibility of collaboration and distributed sensor calibration, and in the mission oriented nature of most sensor networks. Thus our mini track looks at two very important streams of research. After a strict review process nine papers were selected to be included in the program of the minitrack. The first paper is titled “BT-Crowds: Crowds-style Anonymity with Bluetooth and Java,” presenting an interesting idea on how anonymity can be achieved when sending messages in WPAN environments. Our second paper revisits scatternet formation issues of Bluetooth based ad hoc networks thus the title: “A Dynamic and Distributed Scatternet Formation Protocol for Real-life Bluetooth Scatternets.” The third paper is titled “Secure Dynamic Source Routing” and presents a new variant of the DSR routing protocol with special emphasis on security. In the fourth paper, the discussion concerns “Routing Based Feedback towards Applications in Mobile Ad Hoc Networks,” where routing notifications are relayed via event channels. “A Location Service Mechanism for Position-Based Multicasting in Wireless Mobile Ad hoc Networks” is the title of the fifth paper in the minitrack. It presents some innovative ideas on how location information can be managed for multicast communications in ad-hoc networks. In the sixth paper, “Sliding Window Protocol for Secure Group Communication in Ad Hoc Networks,” the authors propose a sliding window protocol for determining multiple routes in a multi-communications environment. In the seventh paper titled “Ad Hoc Routing Protocol Avoiding Route Breaks Based on AODV,” the authors propose improvements to the well-known AODV ad hoc routing protocol The eight paper, “Joint Scheduling and Routing Algorithm for Ad Hoc Wireless,” presents an innovative and interesting idea wrapped around an iterative algorithm on power control. In the final paper of the minitrack, “Performance Issues of Ad Hoc Routing Protocols in a Network Scenario used for VideoPhone Applications,” the authors present a simulation based performance analysis of different ad hoc routing protocols using the application pointed to in the title. These papers highlight some of the issues and work towards solutions in Personal Area and ad hoc networks which are among the most active research fields in wireless networking. We believe that the papers will provide opportunities for researchers to come together and discuss and debate the results of the interesting experiments that are described in the papers. We are confident that the minitrack will achieve its goal of bringing together leading researchers, to present new results and discuss synergies between the two areas. We also take this opportunity to thank all the reviewers for their valuable and professional work as well as all the authors who submitted papers and thus helped us to create such a strong minitrack. We would also like to express our sincere gratitude to the conference organizers for their hard work and help.

Multiple packet reception (MPR) is becoming a viable reality for wireless random access protocols thanks to advances in the physical layer and new coding techniques. In the simplest $K$ -MPR model, a receiver can resolve up to $K\geq 1$ parallel transmissions. We extend the classical analysis of pure and slotted ALOHA to $K$ -MPR devices with arbitrary degree $K$ for fixed and variable packet size. Through a parsimonious modeling approach, we derive relatively simple analytical expressions. In this way, we gain insight and quantitative understanding on the fundamental tradeoffs between pure and slotted ALOHA and on the scaling of maximum achievable throughput with $K$ .

It is our great pleasure to welcome you to the 3rd ACM Workshop on Security of Ad Hoc and Sensor Networks (SASN'05), held in conjunction with the 12th ACM Conference on Computer and Communications Security (CCS'05), November 7, 2005, in Alexandria, Virginia.This year we received a total of 39 submissions on various aspects of ad-hoc and sensor network security. The program committee selected 6 as regular papers that cover a variety of topics, including trust establishment in Mobile Ad-Hoc Networks (MANETs), security of vehicular ad-hoc networks, secure group communication, key pre-distribution for sensor networks, jamming attacks against sensor network MAC protocols, and defense against Denial-of-Service (DoS) attacks. This year we continue the tradition of SASN'03 and SASN'04 to encourage the presentation and discussion of work-in-progress on ad-hoc and sensor network security. Among the 39 submissions, the program committee selected 7 papers to present in work-in-progress sessions, covering topics on anonymous routing for MANETs, key distribution for inter-group multicast in ad-hoc networks, improved topology assumptions for threshold cryptography in MANETs, RFID security, tracing in mobile wireless sensor networks, time synchronization attacks in sensor networks, and coordinated deployment for improving secure communications and sensing coverage in wireless sensor networks. In addition, the program includes a panel on Advances in Sensor and Ad-hoc Network Security and an invited keynote talk by Radha Poovandran (University of Washington) on Information Assurance in MANETs and Wireless Sensor Networks. We hope that these proceedings will serve as a valuable reference for security researchers and developers.

In this paper, we propose an analytical approach for evaluating the performance of finite-user slotted Aloha in wireless networks with multiple packet reception and random traffic. We derive the exact values of the throughput, the average system size, the packet blocking probability, and the average system delay. Our analysis is based on probability theory. We show that our numerical results are identical to simulation results.

A modified bit-map-assisted dynamic queue (BMDQ) protocol is presented for wireless slotted systems with multiple packet reception (MPR) capability and finite user-buffers. As in our BMDQ protocol (Xin Wang and Tugnait, J.K., Proc. Joint Intern. Conf. Wireless LANs & Home Networks and Networking, p.549-60, 2002), in the proposed protocol, the traffic in the channel is viewed as a flow of transmission periods (TP). Each TP has a bit-map (BM) slot at the beginning followed by a data transmission period (DP). In the BMDQ protocol the BM slot is reserved for user detection so that accurate knowledge of the active user set (AUS) can be acquired and in any given TP, each active user is allowed to transmit only one data packet. In the proposed modified BMDQ protocol, the active users are allowed to transmit all data packets in their finite buffer. An active user with more than one packet in its buffer is modeled as several different active pseudo-users. In the BM slot, each user transmits information about the number of data packets in its buffer. Then, according to the number of the active pseudo-users and the channel MPR capability, the protocol attempts to minimize the expected duration of the DP in the same way as the BMDQ protocol. Simulation comparison of the performance of the proposed modified BMDQ protocol with that of the original BMDQ protocol is presented.

Ad-hoc 네트워크 환경에서의 많은 라우팅 알고리즘들은 소스 라우팅 기법을 기초로 설계되었으며 밀집된 ad-hoc 환경에서의 최단경로설정은 짧은 기간동안만 유지되는 제약사항이 존재한다 때문에 SSA와 ABR과 같은 라우팅 프로토콜은 링크 안정성을 고려하여 좀더 안정적인 경로를 탐색한다. 본 논문은 Ad-Hoc network 환경에 현실적으로 적합한 SSA 라우팅 알고리즘을 바탕으로 utilization 메트릭을 고려한 새로운 라우팅 기법에 대해 제안한다. 제안된 방식에서는 SSA의 특정 메트릭에 의한 병목현상을 해결하기 위해 연결을 위한 여러 경로들을 누적 utilization에 따라 분산시키도록 하여 네트워크상의 로드 밸런싱을 추구하였다. 성능 분석을 위해 기존의 라우팅 기법인 AODV와 SSA를 참고 비교 대상으로 하였다. ns-2 네트워크 시뮬레이션 결과 선택되어질 수 있는 안정적인 route가 많은 경우 전체 트래픽이 여러 경로들로 분산되어 경로 재설정(route reconstruction) 횟수를 현저히 줄이는 좋은 성능을 보였다 Many routing algorithms, proposed for ad-hoc wireless networks, we based on source routing scheme and shortest path route has short lifetime especially in highly dense ad-hoc wireless networks. So some routing protocols such as SSA and ABR are considering the link stability and try finding more stable route. In this paper we propose a new routing algorithm considering utilization metric based on SSA routing algerian in Ad-Hoc networks. To reduce the bottleneck by specific metric of SSA, proposed scheme makes load balancing in networks by distributing the connections to several routes. For the evaluation of the performance we compare our scheme with existent routing protocol AODV and SSA. And the results, obtained using the ns-2 network simulation platform, show good performance that reduced the number of reconstructions remarkably by distributing the whole traffic to several routes when there are several stable routes.

Offered load estimation in random access multipacket perception systems using the expectation-maximization algorithm

A mobile packet communication with a chained isolated radio zone network system is proposed that provides nonrealtime media services including voice messages, images, and navigation information, etc., to terminals in cars. In this system, microradio zones are located along a road to establish the communication between a radio base station and a terminal by using packets in a common format. A terminal receives the signal by the paging channel covering a wide area and transmits packets sequentially when a terminal passes radio zones. Therefore, only three radio frequencies, inbound, outbound, and paging channels, are enough and location registration of all terminals is not necessary to realize the proposed system. When transmission and reception of multiple packets is not completed in a single radio zone, it can be done in other radio zones. Since every terminal has a different staying time in each radio zone, the relationship between staying time and throughput, and the relationship between staying time and message transmission ratio are examined and evaluated by the simulation.

An ad-hoc Wireless Local Area Network (WLAN) is a network without infrastructure connectivity where different types of hosts (nodes) exist; such as PDAs (personal digital assistants), laptops and cellular phones. These nodes are equipped with short range transmitters and receivers, and antennas which may be Omni directional (broadcast), highly directional (Point-to-point), or a combination of the two. A Mobile Ad hoc Network (MANET) is a collection of mobile hosts that move in different directions and speeds without the need to maintain connectivity with existing network infrastructure. Different routing protocols have been designed since the existence of ad hoc networks. This work presented below proposes a new routing protocol for ad hoc networks which aims to reduce network overhead, power consumption, Multi-user Interference (MUI), and provide link reliability. In recent years, a vast research has been seen going on in the field of Mobile Ad Hoc Networks (MANETs). Due to limited resources in MANETs, to design an efficient and reliable routing strategy is still a challenge. An intelligent routing strategy is required to efficiently use the limited resources. Also the algorithms designed for traditional wired networks such as link-state or distance vector, does not scale well in wireless environment

We present a computationally efficient method of evaluating the probability of multiple correct packet reception in coded synchronous frequency-hopped spread-spectrum (FHSS) networks. We show that the approximation using the independent receiver operation assumption (IROA), which has been frequently employed in the literature without rigorous validation, produces reasonable results in most network load conditions when compared to the exact computations derived from our proposed method. Specifically, the expected value of the absolute error was in the range of 0.0055%-18.21% in the investigated scenarios.

The next generation mobile communication systems will be based on infrastructure wired/ wireless LAN technologies and ad hoc networks. Such hybrid networks benefit the extension of infrastructure network coverage using ad hoc connectivity apart from offering the ad hoc nodes access to the resources of the wired/infrastructure networks. In most of the integration strategies Mobile IP is integrated with the ad hoc network routing protocol to provide Internet access and in few of the strategies the routing protocol has been enhanced to provide the connectivity without using Mobile IP.Few strategies use fixed gateways, others use mobile gateways. In this paper, we proposed two different approaches of integrating ad hoc network and the wired network using two different protocols. In the first part of this paper, an extended DSDV protocol, named as Efficient DSDV (Eff-DSDV) protocol is used to provide bi-directional connectivity between exclusive ad hoc hosts and the hosts on the Internet (wired network). The proposed framework uses one of the ad hoc hosts known as Mobile Gateway Node (MGN) to act as a bridge between ad hoc network and the Internet. The performance comparison is made between the proposed approach and one of the leading strategies based on packet delivery ratio, end-end delay, and control overhead. The experimental results indicate that the performance of the proposed strategy is better than the existing strategies.Later in the paper, we propose a framework for integrating mobile ad hoc network and the Internet using both fixed and mobile gateways. The ad hoc hosts can access the Internet using either fixed or mobile gateway, based on criteria of distance, load on the gateway. An extended version of AODV routing protocol is used in the framework. The objective behind using both fixed and mobile gateways is to increase the reliability of the Internet access, scalability, providing transparent Internet access to the ad hoc hosts and in general improve the performance of the integrated framework. The proposed framework is a hybrid architecture involving two-layer and three-layer approaches of integration. The performance comparison of the two proposed strategies has been done under common metrics. KeywordsMobile Ad Hoc Network (MANET)Integration StrategyMobile Gateway Node (MGN)Routing ProtocolEff-DSDVFixed GatewaysMobile Gateways

In Ad hoc networks the main purpose is communication without infrastructure and there are many implementations already done on that. There is little effort done for security to prevent threats in ad hoc networks (like MANETs). It is already proven that; there is no any centralized mechanism for defence against threats, such as a firewall, an intrusion detection system, or a proxy in ad hoc networks. Ad hoc networks are very convenient due to its features like self-maintenance, self-organizing and providing wireless communication. In Ad hoc networks there is no fixed infrastructure in which every node works like simply a router which stores and forwards packet to final destination. Due to these dynamic topology features, Ad hoc networks are anywhere, anytime. Therefore, it is necessary to make a secure mechanism for the ad hoc components so that with flexibility they have that security also. This paper shows the secure and flexible implementation about to protect any ad hoc networks. This proposed system design is perfect solution to provide security with flexibility by providing a hybrid system which combines ECC and MAES to detect and prevent Ad hoc network attacks using Intrusion detection system. The complete proposed system designed on NS 2.35 software using Ubuntu (Linux) OS.

The (MANET) ad-hoc mobile network is an automated, network in which android systems link to wireless devices. Ad hoc word means "for this purpose". In MANET any device can easily move in various directions. MANETs (Mobile Ad Hoc Networks) are the basics of broadband networks. In MANET network user can link and get connected anywhere, anytime through communication. MANET introduces a new co system for communication. MANET does not require a fixed structure relies on unconnected ports for service transportation delivery. The temporary hoc network is not dependent on mobile devices (android phones, laptop, PCs, sensors, etc.) that connect exclusively to wireless connectors. Ad-hoc work on a distributed system to provide the required network performance when there is no fixed structure. In this network, it acts as a standalone network or with many attachment points on mobile networks. This paper provides view on the features, applications of ad hoc networks, characteristics and various attacks and challenges faced by programmers and Users . We analyze MANET security objectives and will outline the features, structure, types and challenges of research and the latest trend analysis presented on Mobile Ad Hoc Network to explore open-ended issues in developing navigation strategies for MANET.