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19
AntiCollusion Fingerprinting for Multimedia
 IEEE Transactions on Signal Processing
, 2003
"... Digital fingerprinting is a technique for identifying users who might try to use multimedia content for unintended purposes, such as redistribution. These fingerprints are typically embedded into the content using watermarking techniques that are designed to be robust to a variety of attacks. A cost ..."
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Cited by 76 (24 self)
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Digital fingerprinting is a technique for identifying users who might try to use multimedia content for unintended purposes, such as redistribution. These fingerprints are typically embedded into the content using watermarking techniques that are designed to be robust to a variety of attacks. A coste#ective attack against such digital fingerprints is collusion, where several di#erently marked copies of the same content are combined to disrupt the underlying fingerprints. In this paper, we investigate the problem of designing fingerprints that can withstand collusion and allow for the identification of colluders. We begin by introducing the collusion problem for additive embedding. We then study the e#ect that averaging collusion has upon orthogonal modulation. We introduce an e#cient detection algorithm for identifying the fingerprints associated with K colluders that requires log(n/K)) correlations for a group of n users. We next develop a fingerprinting scheme based upon code modulation that does not require as many basis signals as orthogonal modulation. We propose a new class of codes, called anticollusion codes (ACC), which have the property that the composition of any subset of K or fewer codevectors is unique. Using this property, we can therefore identify groups of K or fewer colluders. We present a construction of binaryvalued ACC under the logical AND operation that uses the theory of combinatorial designs and is suitable for both the ono# keying and antipodal form of binary code modulation. In order to accommodate n users, our code construction requires only # n) orthogonal signals for a given number of colluders. We introduce four di#erent detection strategies that can be used with our ACC for identifying a suspect set of colluders. We demonstrate th...
CollusionResistant Fingerprinting for Multimedia
, 2004
"... A broad overview of the recent advances in multimedia fingerprinting for tracing and identifying colluders. Ensuring that digital content is used for its intended purpose after it has been delivered to customers often requires the ability to track and identify entities involved in unauthorized redis ..."
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Cited by 15 (1 self)
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A broad overview of the recent advances in multimedia fingerprinting for tracing and identifying colluders. Ensuring that digital content is used for its intended purpose after it has been delivered to customers often requires the ability to track and identify entities involved in unauthorized redistribution of multimedia content. Digital fingerprinting is a technology for enforcing digital rights policies whereby unique labels, known as digital fingerprints, are inserted into content prior to distribution. As illustrated in Figure 1, unique fingerprints are assigned to each intended recipient. These fingerprints can facilitate the tracing of the culprits who use their content for unintended purposes. To protect the content, it is necessary that the fingerprints are difficult to remove from the content. For multimedia content, fingerprints can be embedded using conventional watermarking techniques that are typically concerned with robustness against a variety of attacks mounted by an individual. Guaranteeing the appropriate use of multimedia content, however, is no longer a traditional security issue with a single adversary. The global nature of the Internet has brought adversaries closer to each other. It is now easy for a group of users with differently marked versions of the same content to work together and collectively mount attacks against the fingerprints. These attacks, known as multiuser collusion attacks, provide a costeffective method for attenuating each of the colluders ’ fingerprints. An improperly designed embedding and identification scheme may be vulnerable in the sense that a small coalition of colluders can successfully produce a new version of the content with no detectable traces. Thus, collusion poses a real threat to protecting media data and enforcing usage policies. It is desirable, therefore, to design fingerprints that resist collusion and identify the colluders.
Traffic Grooming on the Path
"... In a WDM network, routing a request consists in assigning it a route in the physical network and a wavelength. If each request uses at most 1/C of the bandwidth of the wavelength, we will say that the grooming factor is C. That means that on a given edge of the network we can groom (group) at most C ..."
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Cited by 12 (4 self)
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In a WDM network, routing a request consists in assigning it a route in the physical network and a wavelength. If each request uses at most 1/C of the bandwidth of the wavelength, we will say that the grooming factor is C. That means that on a given edge of the network we can groom (group) at most C requests on the same wavelength. With this constraint the objective can be either to minimize the number of wavelengths (related to the transmission cost) or minimize the number of Add Drop Multiplexers (shortly ADM) used in the network (related to the cost of the nodes). We consider here the case where the network is a path on N nodes, PN. Thus the routing is unique. For a given grooming factor C minimizing the number of wavelengths is an easy problem, well known and related to the load problem. But minimizing the number of ADM’s is NPcomplete for a general set of requests and no results are known. Here we show how to model the problem as a graph partition problem and using tools of design theory we completely solve the case where C = 2 and where we have a static uniform alltoall traffic (one request for each pair of vertices).
Some New characters on the WireTap Channel of Type II
 IEEE Trans. Information Theory
, 2005
"... Abstract—The noiseless wiretap channel of type II with coset coding scheme was provided by Ozarow and Wyner. In this correspondence, the user is split into multiple parties who are coordinated in coding their data symbols by using the same encoder. The adversary can tap not only partial transmitted ..."
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Cited by 5 (0 self)
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Abstract—The noiseless wiretap channel of type II with coset coding scheme was provided by Ozarow and Wyner. In this correspondence, the user is split into multiple parties who are coordinated in coding their data symbols by using the same encoder. The adversary can tap not only partial transmitted symbols but also partial data symbols. We are interested in the equivocation of the data symbols to this adversary who has more power than that of Ozarow and Wyner. The generalized Hamming weight of Wei and the dimension/length profile (DLP) of Forney are extended to twocode formats: relative generalized Hamming weight and relative dimension/length profile (RDLP). Upper and lower bounds of the new concepts are investigated. They are useful to design a perfect secrecy coding scheme for the coordinated multiparty model. Under a general secrecy standard, the coordinated model can provide a higher transmission rate than an uncoordinated (timesharing) model. Index Terms—Dimension/length profile (DLP), generalized Hamming weight, relative dimension/length profile (RDLP), relative generalized Hamming weight, wiretap channel of type II. I.
LDPC Codes Based on Latin Squares: Cycle Structure, Stopping, and Trapping Set Analysis
"... It is well known that certain combinatorial structures in the Tanner graph of a lowdensity paritycheck code exhibit a strong influence on its performance under iterative decoding. These structures include cycles, stopping/trapping sets and parameters such as the diameter of the code. In general, i ..."
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Cited by 5 (1 self)
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It is well known that certain combinatorial structures in the Tanner graph of a lowdensity paritycheck code exhibit a strong influence on its performance under iterative decoding. These structures include cycles, stopping/trapping sets and parameters such as the diameter of the code. In general, it is very hard to find a complete characterization of such configurations in an arbitrary code, and even harder to understand the intricate relationships that exist between these entities. It is therefore of interest to identify a simple setting in which all the described combinatorial structures can be enumerated and studied within a joint framework. One such setting is developed in this paper, for the purpose of analyzing the distribution of short cycles and the structure of stopping and trapping sets in Tanner graphs of LDPC codes based on idempotent and symmetric Latin squares. The paritycheck matrices of LDPC codes based on Latin squares have a special form that allows for connecting combinatorial parameters of the codes with the number of certain subrectangles in the Latin squares. Subrectangles of interest can be easily identified, and in certain instances, completely enumerated. The presented study can be extended in several different directions, one of which is concerned with modifying the code design process in order to eliminate or reduce the number of configurations bearing a negative influence on the performance of the code. Another application of the results includes determining to which extent a configuration governs the behavior of the bit error rate (BER) curve in the waterfall and errorfloor regions.
Design and optimization of packet switching and traffic grooming in WDM optical networks
, 2004
"... Optical packet switching is a longterm strategy to provide highspeed transmission, data transparency, and reconfigurability. Optical buffers are used in the switches to resolve contentions that occur whenever two packets are destined to the same output at the same time slot. Due to the lack of opt ..."
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Cited by 3 (0 self)
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Optical packet switching is a longterm strategy to provide highspeed transmission, data transparency, and reconfigurability. Optical buffers are used in the switches to resolve contentions that occur whenever two packets are destined to the same output at the same time slot. Due to the lack of optical random access memory, fiber delay line (FDL) is currently the only way to implement optical buffering. In general, optical buffering structures can be categorized in two classes: feedforward and feedback, both of which have advantages and disadvantages. In this research, we proposed a more effective hybrid buffering architecture that combines the merits of both schemes. It requires smaller optical device sizes and fewer wavelengths and has less noise than feedback architecture. At the same time, it can facilitate preemptive priority routing which feedforward architecture cannot support. Based on this architecture, we described two switch designs—single plane and multiple plane. The numerical results showed that the new switch architecture can significantly reduce the packet loss probability. The objective of traffic grooming is to save electronics cost by effectively assigning lowrate circuits onto highspeed channels. Generally, we can treat the traffic grooming
Critical Sets in Latin Squares and Associated Structures
, 2001
"... A critical set in a Latin square of order n is a set of entries in an n x n array which can be embedded in precisely one Latin square of order n, with the property that if any entry of the critical set is deleted, the remaining set can be embedded in more than one Latin square of order n. The number ..."
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Cited by 2 (2 self)
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A critical set in a Latin square of order n is a set of entries in an n x n array which can be embedded in precisely one Latin square of order n, with the property that if any entry of the critical set is deleted, the remaining set can be embedded in more than one Latin square of order n. The number of
Almost Resolvable 4Cycle Systems
"... A 4cycle system of order n is said to be almost resolvable provided its 4cycles can be partitioned into (n − 1)/2 almost parallel classes ( = (n − 1)/4 vertex disjoint 4cycles) and a half parallel class ( = (n−1)/8 vertex disjoint 4cycles.) We construct an almost resolvable 4cycle system of eve ..."
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Cited by 2 (2 self)
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A 4cycle system of order n is said to be almost resolvable provided its 4cycles can be partitioned into (n − 1)/2 almost parallel classes ( = (n − 1)/4 vertex disjoint 4cycles) and a half parallel class ( = (n−1)/8 vertex disjoint 4cycles.) We construct an almost resolvable 4cycle system of every order n ≡ 1 (mod 8) except 9 (for which no such system exists) and possibly 33, 41 and 57. 1
The minimum size of complete caps in (Z/nZ) 2
"... A line in (Z/nZ) 2 is any translate of a cyclic subgroup of order n. A subset X ⊂ (Z/nZ) 2 is a cap if no three of its points are collinear, and X is complete if it is not properly contained in another cap. We determine bounds on Φ(n), the minimum size of a complete cap in (Z/nZ) 2. The other natura ..."
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A line in (Z/nZ) 2 is any translate of a cyclic subgroup of order n. A subset X ⊂ (Z/nZ) 2 is a cap if no three of its points are collinear, and X is complete if it is not properly contained in another cap. We determine bounds on Φ(n), the minimum size of a complete cap in (Z/nZ) 2. The other natural extremal question of determining the maximum size of a cap in (Z/nZ) 2 is considered in [8]. These questions are closely related to wellstudied questions in finite affine and projective geometry. If p is the smallest prime divisor of n, weprovethat max{4, √ 2p + 1}≤Φ(n) ≤ max{4,p+1}. 2 We conclude the paper with a large number of open problems in this area. 1