Position-based routing protocols take advantage of location information to perform a stateless and efficient routing. To enable position-based routing, a node must be able to discover the location of the messages' destination node. This task is typically accomplished by a location service. Recently, several location service protocols have been developed for ad hoc networks. In this paper we propose a novel location service called PHLS: Predictive Hierarchical Location Service. In PHLS, the entire network is partitioned into a hierarchy of smaller and smaller regions. For each node, one node in each-level region of the hierarchy is chosen as its local location server. When the network initializes or when a node attaches the network, nodes contact their local location server with their current location information (ie. position and velocity). Then, they only need to update their location server when they move away from their current region. Finally, nodes query their location servers and get the exact or predicted location of destination nodes.
Efficient message forwarding in mobile ad hoc network in disaster scenarios is challenging because location information on the boundary and interior nodes is often unavailable. Information related to boundary nodes can be used to design efficient routing protocols as well as to prolong the battery power of devices along the boundary of an ad hoc network. In this article, we developed an algorithm, CWBound, which discovers boundary nodes in a complex non-convex mobile ad hoc (CNCAH) networks. Experiments show that the CWBound algorithm is at least three times faster than other state-of-the-art …
An Overview of Mobile Ad Hoc Networks for the Existing Protocols and Applications
移动自组织网络（Mobile Ad Hoc Network，MANET）是由两个或两个以上具有无线通信和组网能力的设备或节点或终端组成的集合，这些设备或节点或终端无需任何集中式管理员的帮助即可相互通信，也无需使用任何现有的固定网络基础设施即可动态地组成网络进行信息交换。它是一个自治系统，通过无线链路连接的移动主机可以自由地动态移动，有时同时充当路由器，本文讨论了传统有线网络的鲜明特点，包括网络配置可以随时改变，没有方向或限制移动等，因此需要一个新的可选路径协议路由协议（Routing Protocol）为这些动作确定节点之间相互通信的路径，一个理想的选择协议方式不仅应该能够找到正确的路径，并且adhoc网络必须能够随时适应这种变化的网络。本文详细介绍了Ad Hoc网络的发展历史、无线Ad Hoc网络、无线移动方式和Ad Hoc网络的类型，并提出了13种以上的Ad Hoc网络路由协议。本文对比较有代表性的路由协议，分析各自的特点和优缺点，进行整理和比较，并提出了Ad Hoc网络的所有应用或可能的服务。
Simulation and Performance Analysis of MP-OLSR for Mobile Ad hoc Networks
移动自组织网络（Mobile Ad Hoc Networks，MANDO）是由一组无线移动节点组成的网络，这些节点不依赖于固定的基站或有线骨干网，可以动态地交换数据，这使得路由问题成为自组织网络设计中的一个关键问题。本文讨论了一种混合多路径路由协议MP-OLSR。它基于链路状态算法，采用周期性的消息交换来维护网络的拓扑信息。同时，它以按需方式更新路由表，并在源端确定的多条路径上转发数据包。如果检测到链路故障，算法会自动恢复路由。针对无线网络的不稳定性，采用了冗余编码的方法来提高传输率。NS 2仿真结果表明，新协议能有效地提高网络的性能。
Volume and movement of data rapidly increasing in every type of data communications and networking, and ad hoc networks are not spared from these challenges. Traditional Multipath routing protocols in Mobile Ad-hoc Networks (MANETs) did not focus on data load distribution and balancing as much as required. In this scheme, we have proposed data load distribution and balancing through multiple paths simultaneously. We have considered three important parameters of ad hoc network those are: mobility of node, the energy of node and packet drop rate at a node. This scheme combines these three metric…
Improve performance of tcp new reno over mobile ad-hoc network using abra
在移动自组织网络中，临时链路故障和路由变化频繁发生。假设所有的数据包丢失都是由于拥塞，TCP在这样的环境中表现很差。有许多版本的TCP，根据需要随时修改。本文通过计算新重传超时（RTO），对移动ad-hoc网络上的TCP New Reno协议进行了改进，以提高拥塞控制的性能。为了计算新RTO，应用TCP New Reno中的自适应退避响应方法（ABRA），其建议ABRA New Reno。它利用了一个ABRA拥塞窗口和慢启动阈值减少，每当收到一个确认和新的退避值计算平滑的往返时间。基于ABRA New Reno与其他TCP变体（如New Reno和Reno）的比较研究，使用实际参数（如TCP数据包接收，数据包丢弃，数据包重传，吞吐量和数据包传输率）进行了评估，这些参数是通过改变节点速度，节点数量和传输时间的属性计算的。在QualNet 4.0模拟器中进行实施和模拟。
Power control in reactive routing protocol for Mobile Ad Hoc Network
本文的目的是改变AODV协议（Ad hoc On Demand Vector）的路由策略，以改善移动自组织网络（MANET）中的能量消耗。其目的是尽量减少AODV协议用于路由研究、开发和维护而产生的HELLO消息的定期周期。此信息有助于了解不同网络主机的电池电量水平。在存储这些信息后，节点按照经典模型选择最短路径，利用这些信息选择能量最安全的路径（做出妥协）。发送器节点不选择另一个节点，因为其电池将很快耗尽。网络的任何节点都可以具有关于邻域的相同信息以及关于不同终端的能量水平的其他信息，以避免使用由于该链路中的节点的电池耗尽而将丢失的链路进行路由。Jist/SWANS的分析研究和模拟已经进行了注意到，相对于经典AODV没有发散，节点可以具有这种类型的信息，提高了自组织网络的能量效率。
All networks must provide an acceptable and desirable level of Quality of Service (QoS) to ensure that applications are well supported. This becomes a challenge when it comes to Mobile ad-hoc networks (MANETs). This paper presents a security framework that is QoS-aware in MANETs using a network protocol called Optimized Link State Routing Protocol (OLSR). Security & QoS targets may not necessarily be similar but this framework seeks to bridge the gap for the provision of an optimal functioning MANET. This paper presents the various security challenges, attacks, and goals in MANETs and the exis…
In mobile ad-hoc networks, nodes have to transmit HELLO or Route Maintenance messages at regular intervals, and all nodes residing within its radio range, reply with an acknowledgment message informing their node identifier, current location, and radio-range. Regular transmitting these messages consume a significant amount of battery power in nodes, especially when the set of down-link neighbors does not change over time and the radio-range of the sender node is large. The present article focuses on this aspect and tries to eliminate the number of HELLO messages in existing state-of-art protoc…
This paper aims to propose a system for automatically forming ad hoc networks using mobile phones and battery-powered wireless routers for emergency situations. The system also provides functions to send emergency messages and identify the location of victims based on the network topology information. Optimized link state routing protocol is used to instantly form an ad hoc emergency network based on WiFi signals from mobile phones of the victims, backup battery-powered wireless routers preinstalled in buildings and mobile devices deployed by search and rescue teams. The proposed system is als…
