From the Publisher:
A valuable reference for the novice as well as for the expert who needs a wider scope of coverage within the area of cryptography, this book provides easy and rapid access of information and includes more than 200 algorithms and protocols; more than 200 tables and figures; more than 1,000 numbered definitions, facts, examples, notes, and remarks; and over 1,250 significant references, including brief comments on each paper.

Handbook of Applied Cryptography

We will review some of the major results in random graphs and some of the more challenging open problems. We will cover algorithmic and structural questions. We will touch on newer models, including those related to the WWW.

Random graphs

BIOE 402. Medical Technology Assessment. 2 or 3 hours. Bioentrepreneur course. Assessment of medical technology in the context of commercialization. Objectives, competition, market share, funding, pricing, manufacturing, growth, and intellectual property; many issues unique to biomedical products. Course Information: 2 undergraduate hours. 3 graduate hours. Prerequisite(s): Junior standing or above and consent of the instructor.

“Bioinformatics” 특집을 내면서

An Introduction to MultiAgent Systems.

Border Gateway Protocol (BGP) is the protocol backing the core routing decisions on the Internet. It maintains a table of IP networks or 'prefixes' which designate network reachability among autonomous systems (AS). Point of concern in BGP is its lack of effective security measures which makes Internet vulnerable to different forms of attacks. Many solutions have been proposed till date to combat BGP security issues but not a single one is deployable in practical scenario. Any security proposal with optimal solution should offer adequate security functions, performance overhead and deployment cost. This paper critically analyzes the deployment issues of best three proposals considering trade-off between security functions and performance overhead.

Comparative analysis of

We study the connectivity and diameter of the fault-free part of n-node networks where nodes fail in a random dependent way. To capture fault dependencies, we introduce the neighborhood fault model, where damaging events, called spots, occur randomly and independently with probability p at nodes of a network, causing faults in the given node and its neighbors; faults at distance at most 2 become dependent. We investigate the impact of the spot probability on the connectivity and diameter of the fault-free part of the network. We show a network which has a low diameter with high probability, if p ≤ 1-c log n. We also show that, for constant spot probabilities, most classes of networks do not have their fault-free part connected with high probability. For smaller spot probabilities, connectivity with high probability is supported even by bounded degree networks: the torus supports connectivity with high probability when p e 1-ω(n1-2), and does not when p e 1-O(n1-2); a network built of tori is designed, with the same fault-tolerance properties and additionally having low diameter. We show, however, that for networks of degree bounded above by a constant Δ, the fault-free part can not be connected with high probability if p e 1-O(n1-Δ). This is the first analytic paper which investigates the connectivity and diameter of networks where nodes fail in a random dependent way. © 2009 Wiley Periodicals, Inc. NETWORKS, 2010

A preliminary version of this article appeared in the Proceedings of the 32nd International Symposium on Mathematical Foundations of Computer Science, (MFCS 2007), under the title “Communication in Networks with Random Dependent Faults.”

The diameter and connectivity of networks with random dependent faults

Consider a synchronous system of clients and servers whereby client requests may be satisfied by any one of the servers the clients are assigned to and where the association between clients and servers is determined by an arbitrary but predefined apportionment of the set of servers to clients and of clients to servers. A client can get the required service from any of the servers it is assigned to and at each time step all clients make a request to the servers which then provide the service according to requests. Since clients can make requests simultaneously, if there is no coordination in the "client-to-server" assignment process some clients may have to wait longer if they are assigned simultaneously to a single server when overall performance could improve had they been assigned to separate available servers. Therefore a principal approach to optimizing throughput when assigning client requests to supporting servers, is to keep the client queue sizes well balanced so as to prevent servers from having to remain idle while other servers are being overused. There are several potential examples of such systems involving data gathering and forwarding among sensors in a sensor network or when the servers are base-stations and the clients may be either rotating satellites or other wireless devices, for example. In this paper we consider the problem of finding an assignment of clients to servers that results in all clients receiving a packet while optimally balancing the sizes of remaining queues at the clients. We give a polynomial time algorithm for solving this problem which requires O((m + n)3n) arithmetic operations, where m is the number of client queues and n is the number of servers.

Optimizing data throughput in client/server systems by keeping queue sizes balanced

A random geometric graph, $G(n,r)$, is formed by choosing $n$ points independently and uniformly at random in a unit square; two points are connected by a straight-line edge if they are at Euclidean distance at most $r$. For a given constant $k$, we show that $n^{\frac{-k}{2k-2}}$ is a distance threshold function for $G(n,r)$ to have a connected subgraph on $k$ points. Based on this, we show that $n^{-2/3}$ is a distance threshold for $G(n,r)$ to be plane, and $n^{-5/8}$ is a distance threshold to be planar. We also investigate distance thresholds for $G(n,r)$ to have a non-crossing edge, a clique of a given size, and an independent set of a given size.

Plane and Planarity Thresholds for Random Geometric Graphs

We consider visibility representations of graphs in which the vertices are represented by a collection O of non-overlapping convex regions on the plane. Two points x and y are visible if the straight-line segment xy is not obstructed by any object. Two objects A, B ∈ O are called visible if there exist points x ∈ A, y ∈ B such that x is visible from y. We consider visibility only for a finite set of directions. In such a representation, the given graph is decomposed into a union of unidirectional visibility graphs, for the chosen set of directions. This raises the problem of studying the number of directions needed to represent a given graph. We study this number of directions as a graph parameter and obtain sharp upper and lower bounds for the represent ability of arbitrary graphs.

On the Number of Directions in Visibility Representations

a b s t r a c t Thefocusofthepresentpaperisonprovidingalocaldeterministicalgorithmforcolouring theedgesofYao-likesubgraphsofUnitDiskGraphs.Thesearegeometricgraphssuchthat forsomepositiveintegersl;kthefollowingpropertyholdsateachnodev:ifwepartition theunitcirclecenteredatvinto2kequallysizedwedgestheneachwedgecancontainat mostlpointsdifferentfromv.Weassumethatthenodesarelocationaware,i.e.theyknow theirCartesiancoordinatesintheplane.Thealgorithmpresentedislocalinthesensethat eachnodecanreceiveinformationemanatingonlyfromnodeswhichareatmostaconstant (dependingonkandl,butnotonthesizeofthegraph)numberofhops(measuredinthe originalunderlyingUnitDiskGraph)awayfromit,andhencethealgorithmterminatesin aconstantnumberofsteps.Thenumberofcoloursusedis2klC1andthisisoptimalfor localalgorithms(sincethemaximaldegreeis2klandacolouringwith2klcolourscanonly be constructed by a global algorithm), thus showing that in this class of graphs the price forlocalityisonlyoneadditionalcolour. '2008ElsevierB.V.Allrightsreserved.

Evangelos Kranakis

Papers

The diameter and connectivity of networks with random dependent faults

Optimizing data throughput in client/server systems by keeping queue sizes balanced

Plane and Planarity Thresholds for Random Geometric Graphs

On the Number of Directions in Visibility Representations

LocaledgecolouringofYao-likesubgraphsofUnitDiskGraphs I