Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Probabilistic Model of Keys Generation of QKD Systems   The probabilistic model of keys generation of QKD systems is proposed. The
model includes all phases of keys generation starting from photons generation
to states detection taking characteristics of fiber-optics components into
account. The paper describes the tree of events of QKD systems. Equations are
found for estimation of the effectiveness of the process of sifted keys
generation as well as for bit-error probability and for the rate of private
keys generation.

37
The categories of this paper are: supr-con
19
The categories of this paper are: eess
35
The categories of this paper are: mtrl-th
3
The categories of this paper are: physics
26
The categories of this paper are: bayes-an
2
The categories of this paper are: math
9
The categories of this paper are: nlin
34
The categories of this paper are: chem-ph
28
The categories of this paper are: alg-geom
29
The categories of this paper are: funct-an
21
The categories of this paper are: adap-org
14
The categories of this paper are: math-ph
4
The categories of this paper are: cond-mat
22
The categories of this paper are: chao-dyn
5
The categories of this paper are: gr-qc
12
The categories of this paper are: nucl-th