Hashtabledatastructure Hashfunction Examplehashingcode Whoownsthekeys? •Implementing“mod”efficiently Binaryrepresentationofnumbers Logicalbitoperators 3 AccessingDataByaKey •Studentgrades:(name,grade) E.g.,(“johnsmith”,84),(“janedoe”,93),(“billclinton”,81) ...
•HashTable: –Motivation –DirectAccessTable –HashTable •SolutionsforCollisionProblem: –OpenAddressing: •LinearProbing •QuadraticProbing •DynamicTableExpansion –SeparateChaining 2 Motivation •Wehavetostoresomerecordsandperform thefollowing: ...
Subsequently, in Table 1 we compare existing constructions of chameleon-hashes providing the \(\textsf{W}\text {-}\textsf{CollRes}\), \(\textsf{E}\text {-}\textsf{CollRes}\) and \(\textsf{S}\text {-}\textsf{CollRes}\) notions with instantiations of our approach (in the rando...
A chameleon-hash function is a hash function that involves a trapdoor the knowledge of which allows one to find arbitrary collisions in the domain of the function. In this paper, we introduce the notion ofchameleon-hash functions with ephemeral trapdoors. Such hash functions feature additional, i...
Fig. 1. 64 bytes from the file 007533.xls shows the “ramp” structure of the Microsoft Office Sector Allocation Table. The existence of such common blocks complicates hash-based carving in two ways. First, because these blocks match multiple files, they cannot be used for Candidate Selection...
We introduce the notion of lattice-based PHFs by carefully exploiting the specific algebraic structure of lattices. As the traditional PHFs, our lattice-based PHFcan work in two modes. Given a keyKgenerated in either the normal mode or the trapdoor mode, the hash functionmaps its inputinto ...
hashingindepth. Description •Ahashtableisadatastructurethatstores thingsandallowsinsertions,lookups,and deletionstobeperformedinO(1)time. •Analgorithmconvertsanobject,typicallya string,toanumber.Thenthenumberis compressedaccordingtothesizeofthetable ...
any patterns that might exist in the data. » E.g. Each key is drawn independently from U according to a probability distribution P: k:h(k) = j P(k) = 1/m for j = 0, 1, … , m–1. » An example is the division method. hashtables - 19 Lin / Devi Comp 122, Fall ...
Additional applications of our new primitive may include revocable signatures [43], but also simulatable equivocable commitments [34]. However, in contrast to equivocable commitments, we want that parties can actually equivocate, not only a simulator. Therefore, we chose to call this primitive a ...
Only a few works successfully encompass more than five of the listed properties in Table 1, such as [14]. Table 1. Security and functionality comparisons of redactable blockchain. Current research on redactable blockchains predominantly focuses on two main areas: fine-grained redaction and ...