Let G=(V, E) be an undirected graph and C a subset of vertices. If the sets B r (v) 5 C, v ยฅ V, are all nonempty and different, where B r (v) denotes the set of all points within distance r from v, we call C an r-identifying code. We give bounds on the best possible density of r-identifying codes in
On Codes with the Identifiable Parent Property
โ Scribed by Henk D.L Hollmann; Jack H van Lint; Jean-Paul Linnartz; Ludo M.G.M Tolhuizen
- Publisher
- Elsevier Science
- Year
- 1998
- Tongue
- English
- Weight
- 217 KB
- Volume
- 82
- Category
- Article
- ISSN
- 0097-3165
No coin nor oath required. For personal study only.
โฆ Synopsis
If C is a q-ary code of length n and a and b are two codewords, then c is called a descendant of a and b if c i # [a i , b i ] for i=1, ..., n. We are interested in codes C with the property that, given any descendant c, one can always identify at least one of the ``parent'' codewords in C. We study bounds on F(n, q), the maximal cardinality of a code C with this property, which we call the identifiable parent property. Such codes play a role in schemes that protect against piracy of software.
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