Link-disjoint embedding of complete binary trees in meshes

title: Contention free embedding of complete binary trees into 3D meshes in half and full-duplexed network models
abstract: We consider the problem of dimension-ordered embedding of complete binary trees into 3-dimensional meshes without link contention. In this paper, the embedding problems are studied under two different network models: half-duplexed networks and full-duplexed networks. Gibbons and Paterson showed that a complete binary tree T/sub p/ could be disjointedly embedded into a full-duplexed 2-dimensional mesh of optimum size without dimension-ordered routing. Using the dimension-ordered routing, the authors showed that T/sub p/ could be embedded into a 3-dimensional mesh of optimum size with link congestion two. This paper presents the dimension-ordered embedding algorithms of the complete binary trees into the wormhole routed 3-dimensional meshes without link contention achieving expansion of no larger than 1.125 of optimum in half-duplexed network model and optimum in full-duplexed network model.

title: Embedding of Complete Binary Trees into Meshes with Row-Column Routing
abstract: This paper considers the problem of embedding complete binary trees into meshes using the row-column routing and obtained the following results: a complete binary tree with 2/sup p/-1 nodes can be embedded (1) with link congestion one into a /sup 9///sub 8//spl radic/(2/sup p/)/spl times//sup 9///sub 8//spl radic/(2/sup p/) mesh when p is even and a /spl radic/(/sup 9///sub 8/2/sup p/)/spl times//spl radic/(/sup 9///sub 8/2/sup p/) mesh when p is odd, and (2) with link congestion two into a /spl radic/(2/sup p/)/spl times//spl radic/(2/sup p/) mesh when p is even, and a /spl radic/(2/sup p-1/)/spl times//spl radic/(2/sup p-1/) mesh when p is odd.

title: Optimal Transmission Schedules in TWDM Optical Passive Star Networks
abstract: This paper is concerned with optimal transmission schedules in the TWDM (time and wavelength division multiplexed) optical passive star network. Our model of the network consists of a set V of N nodes with N tunable transmitters and N fixed-tuned receivers (where each node is assigned a transmitter-receiver pair), k wavelengths (each wavelength is shared by N k receivers where N k is an integer), and tuning time δ > 0 (in units of time slot, for transmitters to tune from one wavelength to another). We assume that at any given time slot, at most one transmission can be done per wavelength. An optimal transmission schedule is defined to be the one that schedules transmissions such that for each node v in V, the transmitter in v transmits once to every receiver in V — {v} within a repeating cycle of minimum length. We present an optimal transmission schedule for each tuning time, and show that the cycle length of any optimal transmission schedule is max {N(N — 1)/k, kδ + N — 1}.

title: Distribution of path durations in mobile ad-hoc networks - Palm's Theorem to the rescue
abstract: We first study the distribution of path duration in multi-hop wireless networks. We show that as the number of hops along a path increases, the path duration distribution can be accurately approximated by an exponential distribution under a set of mild conditions, even when the link duration distributions are not identical. Then, we develop an approximate model for computing the distribution of link duration under a Random Waypoint (RWP) mobility model, and demonstrate that the path duration distribution converges to an exponential distribution with increasing number of hops. Simulation results obtained using ns-2 simulator are provided to validate the analysis.

title: Designated Verification of Non-invertible Watermark
abstract: Digital watermark has been proposed as the means for copyright protection of multimedia data in network-based distribution framework. However, existing digital watermarking mechanisms have some problems that they cannot resolve the rightful ownership alone. Specially, someone can provide counterfeited watermark which can be performed on a watermarked image to allow multiple claims of rightful ownership. In this paper, we use designated verification method for undeniable signatures in the watermarking process. The confirmer of watermark can sure that only the intended verifier(s) can be convinced about the validity or invalidity of the signature.

title: Performance of Group Key Agreement Protocols over Multiple Operations
abstract: ∗Shanyu Zheng and Jim Alves-FossCenter for Secure and Dependable SystemsUniversity of IdahoMoscow, ID 83844,  LeeDepartment of StatisticsUnversity of IdahoMoscow, ID 83844,  stevel@uidaho.eduABSTRACTA few group key protocols are analyzed, implemented anddeployed, but the costs associated with them have beenpoorly understood. Their analysis of group key agreementsperformance is based on the cost of performing a single op-eration. In this paper we extend this analysis to examine theperformance behavior of ﬁve group key protocols after ex-ecution of multiple operation. We report our experimentalresults for 100 operations consist of combinations of join,leave, mass join, mass leave, merge, and partition. In orderto thoroughly compare the performance of ﬁve protocols,we simulate three group operations: join-leave-mass join-mass leave, merge-partition, and join-leave-mass join-massleave-merge-partition to observe what is not apparent fromthe theoretical analysis.KEY WORDSgroup key management, group communications, crypto-graphic protocols

title: Interactive Multiresolution Editing of Arbitrary Meshes
abstract: This paper presents a novel approach to multiresolution editing of a triangular mesh. The basic idea is to embed an editing area of a mesh onto a 2D rectangle and interpolate the user-specified editing information over the 2D rectangle. The result of the interpolation is mapped back to the editing area and then used to update the mesh. We adopt harmonic maps for the embedding and multilevel B-splines for the interpolation. The proposed mesh editing technique can handle an arbitrary mesh without any preprocessing such as remeshing. It runs fast enough to support interactive editing and produces intuitive editing results.

title: High Quality Perceptual Steganographic Techniques
abstract: Recently, several steganographic algorithms for two-color binary images have been proposed [16,1,14,2]. In this paper, we propose steganographic algorithms which embeds a secret message into bitmap images and palette-based images. To embed a message, the suggested algorithm divides a bitmap image into bit-plane images from LSB-plane to MSB-plane for each pixel, and considers each bit-plane image as a binary one. The algorithm splits each bit-plane image into m × n blocks, and embeds a r-bit(\(r = \lfloor {\rm log_2}(mn + 1) \rfloor - 1\)) message into the block. And our schemes embed a message to every bit-plane from LSB to MSB to maximize the amount of embedded message and to minimize the degradation. The schemes change at most two pixels in each block. Therefore, the maximal color changes of the new algorithm are much smaller than other bit-plane embedding schemes’ such as the sequential substitution schemes [10,7,11].