Abstract

Scenarios such as online banking, mobile payment systems, stock trading, selling merchandise, and a host of other applications that need a high level of security have moved from the research domain to real world. Moreover, the nature of clients has been changing from traditional desktops to mobile and handheld devices. Protocols like SSL, SSH are the present standard for establishing secure channels. However, the drawback in these protocols is that both the server and the client need to perform computationally expensive public-key operations for secure channel establishment. In this paper, we present simple constructions that spread the cost of secure channel establishment over several sessions. Our constructions are incrementally deployable and can operate with existing protocols such as SSL and SSH. Experimental results indicate that our constructions are practical and efficient in reducing the computational load at the server as well as the client side.

Abstract

In this paper, we address the security of routing protocols. Internet routing protocols are subject to attacks in the control plane as well as the data plane. In the control plane, a routing protocol, e.g., BGP, OSPF, exchanges routing state updates and enables routers to compute the best paths towards various destinations. During this phase, an attacker can modify or inject malicious control messages leading to incorrect computation of routing paths. In the data plane, the routers forward the data along the paths computed in the control plane. Even if an attacker is not successful during the control phase, he can choose not to use the correct routing paths and forward data along routes that benefit him. Research shows that, attacks on the control plane can be mitigated by ensuring message integrity and, attacks on the data plane can be mitigated by ensuring route integrity. Earlier works have addressed these two problems independently with many interesting solutions. However, due to the nature of these solutions, network architects cannot deploy security at both planes without increasing the overhead on the network. In this paper, we focus on an integrated approach and propose the use of symmetric key protocols for addressing the security at both the control and data planes. We describe approaches that enable the reuse of the symmetric key protocols thereby eliminating the need for separate solutions at different planes. We used symmetric key protocols as they are efficient and scalable. Our experimental results show that our approaches are practical and can be incrementally deployed as well.

Abstract

people volunteer their time and energy and work in a dedicated fashion to pull everything together each year, including our very supportive Steering Comm-tee members led by Sukumar Ghosh. However, the success of ICDCN is mainly due to the hard work of all those people who submit papers and/or attend the conference. We thank you all. January 2009 Prasad Jayanti Andrew T. Campbell Message from the Technical Program Chairs Welcome to the proceedings of the 10thInternationalConferenceon Distributed Computing and Networking (ICDCN) 2009. As ICDCN celebrates its 10th-niversary, ithasbecomeanimportantforumfordisseminatingthelatestresearch results in distributed computing and networking. We received 179 submissions from all over the world, including Algeria, A-tralia, Canada, China, Egypt, France, Germany, Hong Kong, Iran, Italy, Japan, Malaysia, The Netherlands, Poland, Singapore, South Korea, Taiwan, and the USA, besides India, the host country. The submissions were read and evaluated by the Program Committee, which consisted of 25 members for the Distributed Computing Track and 28 members for the Networking Track, with the ad-tional help of external reviewers. The Program Committee selected 20 regular papers and 32 short papers for inclusion in the proceedings and presentation at the conference. We were fortunate to have several distinguished scientists as keynote speakers. Andrew Campbell (Dartmouth College, USA), Maurice Herlihy (Brown University, USA), and PR Kumar (University of of Illinois, Urbana-Champaign) delivered the keynote address. Krithi Ramamritham from IIT Bombay, India

Abstract

General purpose programming on the graphics processing units (GPGPU) has received a lot of attention in the parallel computing community as it promises to offer the highest performance per dollar. The GPUs have been used extensively on regular problems that can be easily parallelized. In this paper, we describe two implementations of List Ranking, a traditional irregular algorithm that is difficult to parallelize on such massively multi-threaded hardware. We first present an implementation of Wyllie's algorithm based on pointer jumping. This technique does not scale well to large lists due to the suboptimal work done. We then present a GPU-optimized, Recursive Helman-JaJa (RHJ) algorithm. Our RHJ implementation can rank a random list of 32 million elements in about a second and achieves a speedup of about 8-9 over a CPU implementation as well as a speedup of 3-4 over the best reported implementation on the Cell Broadband engine. We also discuss the practical issues relating to the implementation of irregular algorithms on massively multi-threaded architectures like that of the GPU. Regular or coalesced memory accesses pattern and balanced load are critical to achieve good performance on the GPU.

Abstract

An acyclic vertex coloring of a graph is a proper vertex coloring such that there are no bichromatic cycles. The acyclic chromatic number of G, denoted a (G), is the minimum number of colors required for acyclic vertex coloring of graph G=(V, E). In this paper we show that for any graph G with maximum degree∆, a (G)≤ 3∆ 2+ 4∆+ 8

Abstract

The significant growth in computational power of modern Graphics Processing Units (GPUs) coupled with the advent of general purpose programming environments like NVIDIA's CUDA, has seen GPUs emerging as a very popular parallel computing platform. Till recently, there has not been a performance model for GPGPUs. The absence of such a model makes it difficult to definitively assess the suitability of the GPU for solving a particular problem and is a significant impediment to the mainstream adoption of GPUs as a massively parallel (super)computing platform. In this paper we present a performance prediction model for the CUDA GPGPU platform. This model encompasses the various facets of the GPU architecture like scheduling, memory hierarchy, and pipelining among others. We also perform experiments that demonstrate the effects of various memory access strategies. The proposed model can be used to analyze pseudo code for a CUDA kernel to obtain a performance estimate, in a way that is similar to performing asymptotic analysis. We illustrate the usage of our model and its accuracy with three case studies: matrix multiplication, list ranking, and histogram generation.

Abstract

We consider the problem of probabilistic reliable communication (PRC) over synchronous networks modeled as directed graphs in the presence of a Byzantine adversary when players’ knowledge of the network topology is not complete. We show that possibility of PRC is extremely sensitive to the changes in players’ knowledge of the topology. This is in complete contrast with earlier known results on the possibility of perfectly reliable communication over undirected graphs where the case of each player knowing only its neighbours gives the same result as the case where players have complete knowledge of the network. Specifically, in either case,(2t+ 1)-vertex connectivity is necessary and sufficient, where t is the number of nodes that can be corrupted by the adversary [DDWY93, SKR+05]. We introduce a novel model for quantifying players’ knowledge of network topology, denoted by T K. Given a directed graph G, influenced by a Byzantine adversary that can corrupt up to any t players, we give a necessary and sufficient condition for possibility of PRC over G for any arbitrary topology knowledge T K. It follows from our main characterization theorem that knowledge of up to d=⌊ n− 2t

Abstract

We address the problem of message authentication in communication networks which are resource constrained or are performance bound. Recent research has focused on development of symmetric key protocols for authentication in such networks. In these protocols, the sender generates a pool of keys -used to sign the messages, and distributes a different subset of keys -used to verify the signatures, to each user. However, in these protocols, users can collude to combine their keys and impersonate the sender by generating the sender signatures. In this work, we describe a family of collusion resistant symmetric key distribution protocols for authentication which address the problem of collusion. We show that the collusion resistance achieved using our protocols is practical (and hence, sufficient) for networks whose communication diameter is known or is within fixed bounds. Furthermore, we show that some existing protocols in literature are members of our family of protocols.

Abstract

This paper focuses on anti-magic labellings of planar graphs of type (a, b, c) introduced by Lih (Util. Math. 24 (1983), 165–197). We show that a certain class of planar graphs defined using the complete graphs and a class of planar graphs defined using the complete bipartite graphs are (1, 1, 0) and (1, 1, 1)-anti-magic under certain mild conditions.

Abstract

This paper considers the problem of unicasting in wireless ad hoc networks. Unicasting is the problem of finding a route between a source and a destination and forwarding the message from the source to the destination. In theory, models that have been used oversimplify the problem of route discovery in ad hoc networks. The achievement of this paper is threefold. First we use a more general model in which nodes can have different transmission and interference ranges and we present a new routing algorithm for wireless ad hoc networks that has several nice features. We then combine our algorithm with that of known greedy algorithms to arrive at an average case efficient routing algorithm in the situation that GPS information is available. Finally we show how to schedule unicast traffic between a set of source-destination pairs by providing a proper vertex coloring of the nodes in the wireless ad hoc network. Our coloring algorithm achieves a O(Δ)–coloring that is locally distinct within the 2-hop neighborhood of any node.