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Rebroadcasting Neighbour Coverage Routing Protocol in MANET using MAC layer Design
"... In MANET broadcasting is a virtual role which covers the neighbour to reach destination, its resolves many issues in Mobile Ad hoc Network. Dynamic change of radio frequency leads to un-covered neighbour search in network. In this rebroadcasting cause’s congestion among radio signals, it overlap the ..."
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In MANET broadcasting is a virtual role which covers the neighbour to reach destination, its resolves many issues in Mobile Ad hoc Network. Dynamic change of radio frequency leads to un-covered neighbour search in network. In this rebroadcasting cause’s congestion among radio signals, it overlap the neighbour coverage and initiates the flooding and results in redundancy, Routing Overhead, and collision in MAC layer, In particular, due to mobility environment in network link failure and neighbour coverage problem e.g., (radio frequency or) bandwidth congestion occur. Collision avoidance is a storm difficult in network, thus MAC follow a Carrier Sense Multiple Access / Collision Avoidance (CSMA/CA) mechanism in MAC layer design to improve the channel allocation of data transmission. We proposed a protocol (RBNC) Rebroadcasting Neighbour Coverage protocol which reduces the high channel contention causing redundant and reduce routing overhead by Retransmissions. Routing path can be reduced using the delay tolerant (DTN) of intermediate nodes (i.e. the number of RREQ packets transmitted during route discovery is reduced).Our protocol is simulated in NS2 and the performance is evaluated and the rebroadcasting is analytically discussed.
Reliable Broadcast in Unknown Fixed-Identity Networks
"... In this paper, we formulate a new theoretical problem, namely the reliable broadcast problem in unknown fixedidentity networks. This problem arises in the context of developing decentralized security mechanisms in a specificclass of distributed systems: Consider an undirected graph G connecting n no ..."
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In this paper, we formulate a new theoretical problem, namely the reliable broadcast problem in unknown fixedidentity networks. This problem arises in the context of developing decentralized security mechanisms in a specificclass of distributed systems: Consider an undirected graph G connecting n nodes where each node is aware of only its neighbors but not of the entire graph. Additionally, each node has a unique identity and cannot fake its identity to its neighbors. Assume that k among the n nodes act in an adversarial manner and the remaining n−k are good nodes. Under what constraints does there exist a distributed algorithm Γ that enables every good node v to reliably broadcast a message m(v) to all other good nodes in G? While good nodes follow the algorithm Γ, an adversary can additionally discard messages, generate spurious messages or collude with other adversaries. In this paper, we prove two results on this problem. First, we provide a distributed algorithm Γ that can achieve reliable broadcast in an unknown fixed-identity network in the presence of k adversaries if G is 2k+1 vertex connected. Additionally, a minimum vertex connectivity of 2k + 1 is a necessary condition for achieving reliable broadcast. Next, we study the problem of reliable broadcast in sparse networks (1−connected and 2-connected) in the presence of a single adversary i.e., k = 1. In sparse networks, we show that a single adversary can partition the good nodes into groups such that nodes within a group can reliably broadcast to each other but nodes across groups cannot. For 1−connected and 2−connected graphs, we prove lower bounds on the number of such groups and provide a distributed algorithm to achieve these lower bounds. We also show that in a powerlaw random graph G(n, α), a single adversary can partition
Trust- and Clustering-based Authentication Service in MANET
, 2004
"... The Chinese University of Hong Kong holds the copyright of this thesis. Any person(s) intending to use a part or whole of the materials in the thesis in a proposed publication must seek copyright release from the Dean of the Graduate School. Abstract of thesis entitled: ..."
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The Chinese University of Hong Kong holds the copyright of this thesis. Any person(s) intending to use a part or whole of the materials in the thesis in a proposed publication must seek copyright release from the Dean of the Graduate School. Abstract of thesis entitled:
A Hierarchical IP Addressing Scheme for Mobile Ad-hoc Networks
"... MANET (Mobile Ad-hoc Networks) have emerged as a new promising networking technology that allows groups of nodes to organize themselves in order to form a spontaneous network without the use of any central entities for configuration or routing (e.g. DHCP server). Therefore, new auto-configuration te ..."
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MANET (Mobile Ad-hoc Networks) have emerged as a new promising networking technology that allows groups of nodes to organize themselves in order to form a spontaneous network without the use of any central entities for configuration or routing (e.g. DHCP server). Therefore, new auto-configuration techniques to configure addressing parameters (mainly the IP address) are needed. Those new techniques are required to operate dynamically in order to reconfigure the nodes with new parameters while they move. Since MANET nodes have to rely on themselves in all aspects of the configuration process, this type of configuration is therefore called auto-configuration or self-configuration. In general the routing mechanism of any network relies on the architecture of the addresses configuration scheme; hierarchical routing requires hierarchical addressing, while flat routing requires flat addressing. MANET scalability is becoming a very critical problem that is yet to be solved. For MANET to be scalable, a hierarchical routing scheme is required, that in turn requires a hierarchical addressing scheme to be in place before the hierarchical routing can get involved. In this paper, we present a new IPV4 based hierarchical addressing technique for MANET. The scheme allows (with some modifications) regular IP based flat MANET routing protocols (e.g. Dynamic Source Routing, Ad-hoc On-demand Distance Victor) to provide hierarchical IP routing and hence achieve the required MANET scalability. 1
Key Management in Wireless Ad Hoc Networks: Collusion Analysis and Prevention
"... Due to the dynamic nature of WAHN communications and the multi-node involvement in most WAHN applications, group key management has been proposed for efficient support of secure communications in WAHNs. Exclusion Basis Systems (EBS) provide a framework for scalable and efficient group key management ..."
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Due to the dynamic nature of WAHN communications and the multi-node involvement in most WAHN applications, group key management has been proposed for efficient support of secure communications in WAHNs. Exclusion Basis Systems (EBS) provide a framework for scalable and efficient group key management where the number of keys per node and the number of re-key messages can be relatively adjusted. EBS-based solutions, however, may suffer from collusion attacks, where a number of nodes may collaborate to reveal all system keys and consequently capture the network. In this paper we investigate the collusion problem in EBS and demonstrate that a careful assignment of keys to nodes reduces collusion. Since an optimal assignment is NP hard, we propose a location-based heuristic where keys are assigned to neighboring nodes depending on the hamming distance between the strings of bits representing the used subset of the keys employed in the system. Simulation results have demonstrated that our proposed solution significantly boosts the network resilience to potential collusion threats.
Broadcasting in Ad Hoc Networks Based on Self-Pruning
"... Abstract — We propose a general framework for broadcasting in ad hoc networks through self-pruning. The approach is based on selecting a small subset of hosts (also called nodes) to form a forward node set to carry out a broadcast process. Each node, upon receiving a broadcast packet, determines whe ..."
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Abstract — We propose a general framework for broadcasting in ad hoc networks through self-pruning. The approach is based on selecting a small subset of hosts (also called nodes) to form a forward node set to carry out a broadcast process. Each node, upon receiving a broadcast packet, determines whether to forward the packet based on two neighborhood coverage conditions proposed in this paper. These coverage conditions depend on neighbor connectivity and history of visited nodes, and in general, resort to global network information. Using local information such as k-hop neighborhood information, the forward node set is selected through a distributed and local pruning process. The forward node set can be constructed and maintained through either a proactive process (i.e., “up-to-date”) or a reactive process (i.e., “on-the-fly”). Several existing broadcast algorithms can be viewed as special cases of the coverage conditions with k-hop neighborhood information. Simulation results show that new algorithms, which are more efficient than existing ones, can be derived from the coverage conditions, and self-pruning based on 2- or 3-hop neighborhood information is relatively cost-effective. Index Terms—- Ad hoc networks, broadcasting, localized algorithms, pruning. 1
International Journal of Foundations of Computer Science c ○ World Scientific Publishing Company BROADCASTING IN AD HOC NETWORKS BASED ON SELF-PRUNING ∗
"... Communicated by Editor’s name We propose a general framework for broadcasting in ad hoc networks through selfpruning. The approach is based on selecting a small subset of hosts (also called nodes) to form a forward node set to carry out a broadcast process. Each node, upon receiving a broadcast pack ..."
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Communicated by Editor’s name We propose a general framework for broadcasting in ad hoc networks through selfpruning. The approach is based on selecting a small subset of hosts (also called nodes) to form a forward node set to carry out a broadcast process. Each node, upon receiving a broadcast packet, determines whether to forward the packet or not based on two neighborhood coverage conditions proposed in this paper. These coverage conditions depend on neighbor connectivity and history of visited nodes, and in general, resort to global network information. Using local information such as k-hop neighborhood information, the forward node set is selected through a distributed and local pruning process. The forward node set can be constructed and maintained through either a proactive process (i.e., “up-to-date”) or a reactive process (i.e., “on-the-fly”). Several existing broadcast algorithms can be viewed as special cases of the coverage conditions with k-hop neighborhood information. Simulation results show that new algorithms, which are more efficient than existing ones, can be derived from the coverage conditions, and self-pruning based on 2- or 3-hop neighborhood information is relatively more cost-effective.
