No abstract

No abstract

No abstract

This paper introduces a novel technique called protocol threading, yielding a deterministic protocol that gives a guaranteed upper bound on the transmission delay of each packet at every node in a multihop mobile network. By eliminating the maximum degree constraint, the new method improves upon existing time-spread multiple-access (TSMA)-type protocols while preserving the advantages of the deterministic operation and topology transparency. In this paper we introduce the protocol threading solution, derive the maximum delay bound in a mobile topology, and analyze the performance of the protocol.

In this paper we analyze the worst-case behavior of general connection-oriented networks, with first-in-first-out (FIFO) queueing policy, forwarding packets along an arbitrary system of routes. A worst-case bound is proven for the end-toend queueing delay and buffer size needed to guarantee lossfree packet delivery, given that sources satisfy a given source rate condition. The results are based on a novel deterministic approach and help in reconciling the discrepancy between the unstable worst-case behavior of FIFO-based networks and their good practical performance.Index Terms-Deterministic delay bound, FIFO, packet flow.

No abstract

Unlike a cellular or wired network, there is no base station or network infrastructure in a wireless ad-hoc network, in which nodes communicate with each other via peer communications. In order to make routing and flooding efficient in such an infrastructureless network, Connected Dominating Set (CDS) as a virtual backbone has been extensively studied. Most of the existing studies on the CDS problem have focused on unit disk graphs, where every node in a network has the same transmission range. However, nodes may have different powers due to difference in functionalities, power control, topology control, and so on. In this case, it is desirable to model such a network as a disk graph where each node has different transmission range.In this paper, we define Minimum Strongly Connected Dominating and Absorbent Set (MSCDAS) in a disk graph, which is the counterpart of minimum CDS in unit disk graph. We propose a constant approximation algorithm when the ratio of the maximum to the minimum in transmission range is bounded. We also present two heuristics and compare the performances of the proposed schemes through simulation.

A fast nearest-neighbor algorithm is presented. It works in general spaces where the known cell (bucketing) techniques cannot be implemented for various reasons, such as the absence of coordinate structure andor high dimensionality. The central idea has alreody appeared several times in the literature with extensive computer simulation results. This paper provides an exact probabilistic analysis of this family of algorithms, proving its O(1) asymptotic average complexity measured in the nnmber of dissimilarity calculations. Indcx Tenns-Average complexity, dissimilarity spaces, fast nearestneighbor search, pattern recognition, probabilistic analysis of algorithms.