Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Fog Computing Approaches in Smart Cities: A State-of-the-Art Review   These days, the development of smart cities, specifically in location-aware,
latency-sensitive, and security-crucial applications (such as emergency fire
events, patient health monitoring, or real-time manufacturing) heavily depends
on a more advance computing paradigms that can address these requirements. In
this regard, fog computing, a robust cloud computing complement, plays a
preponderant role by virtue of locating closer to the end-devices. Nonetheless,
utilized approaches in smart cities are frequently cloud-based, which causes
not only the security and time-sensitive services to suffer but also its
flexibility and reliability to be restricted. So as to obviate the limitations
of cloud and other related computing paradigms such as edge computing, this
paper proposes a systematic literature review (SLR) for the state-of-the-art
fog-based approaches in smart cities. Furthermore, according to the content of
the reviewed researches, a taxonomy is proposed, falls into three classes,
including service-based, resource-based, and application-based. This SLR also
investigates the evaluation factors, used tools, evaluation methods, merits,
and demerits of each class. Types of proposed algorithms in each class are
mentioned as well. Above all else, by taking various perspectives into account,
comprehensive and distinctive open issues and challenges are provided via
classifying future trends and issues into practical sub-classes.

25
The categories of this paper are: patt-sol
3
The categories of this paper are: physics
13
The categories of this paper are: quant-ph
8
The categories of this paper are: hep-ex
35
The categories of this paper are: mtrl-th
17
The categories of this paper are: q-fin
2
The categories of this paper are: math
14
The categories of this paper are: math-ph
24
The categories of this paper are: dg-ga
30
The categories of this paper are: q-alg
18
The categories of this paper are: econ
10
The categories of this paper are: q-bio
37
The categories of this paper are: supr-con
33
The categories of this paper are: plasm-ph
6
The categories of this paper are: astro-ph
0
The categories of this paper are: hep-ph