Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantifying information flow in interactive systems   We consider the problem of quantifying information flow in interactive
systems, modelled as finite-state transducers in the style of Goguen and
Meseguer. Our main result is that if the system is deterministic then the
information flow is either logarithmic or linear, and there is a
polynomial-time algorithm to distinguish the two cases and compute the rate of
logarithmic flow. To achieve this we first extend the theory of information
leakage through channels to the case of interactive systems, and establish a
number of results which greatly simplify computation. We then show that for
deterministic systems the information flow corresponds to the growth rate of
antichains inside a certain regular language, a property called the width of
the language. In a companion work we have shown that there is a dichotomy
between polynomial and exponential antichain growth, and a polynomial time
algorithm to distinguish the two cases and to compute the order of polynomial
growth. We observe that these two cases correspond to logarithmic and linear
information flow respectively. Finally, we formulate several attractive open
problems, covering the cases of probabilistic systems, systems with more than
two users and nondeterministic systems where the nondeterminism is assumed to
be innocent rather than demonic.

17
The categories of this paper are: q-fin
19
The categories of this paper are: eess
14
The categories of this paper are: math-ph
6
The categories of this paper are: astro-ph
27
The categories of this paper are: comp-gas
31
The categories of this paper are: ao-sci
11
The categories of this paper are: hep-lat
8
The categories of this paper are: hep-ex
32
The categories of this paper are: atom-ph
18
The categories of this paper are: econ
7
The categories of this paper are: hep-th
10
The categories of this paper are: q-bio
36
The categories of this paper are: cmp-lg
24
The categories of this paper are: dg-ga
15
The categories of this paper are: nucl-ex
37
The categories of this paper are: supr-con