Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: GNSS-based positioning: Attacks and Countermeasures   Increasing numbers of mobile computing devices, user-portable, or embedded in
vehicles, cargo containers, or the physical space, need to be aware of their
location in order to provide a wide range of commercial services. Most often,
mobile devices obtain their own location with the help of Global Navigation
Satellite Systems (GNSS), integrating, for example, a Global Positioning System
(GPS) receiver. Nonetheless, an adversary can compromise location-aware
applications by attacking the GNSS-based positioning: It can forge navigation
messages and mislead the receiver into calculating a fake location. In this
paper, we analyze this vulnerability and propose and evaluate the effectiveness
of countermeasures. First, we consider replay attacks, which can be effective
even in the presence of future cryptographic GNSS protection mechanisms. Then,
we propose and analyze methods that allow GNSS receivers to detect the
reception of signals generated by an adversary, and then reject fake locations
calculated because of the attack. We consider three diverse defense mechanisms,
all based on knowledge, in particular, own location, time, and Doppler shift,
receivers can obtain prior to the onset of an attack. We find that inertial
mechanisms that estimate location can be defeated relatively easy. This is
equally true for the mechanism that relies on clock readings from off-the-shelf
devices; as a result, highly stable clocks could be needed. On the other hand,
our Doppler Shift Test can be effective without any specialized hardware, and
it can be applied to existing devices.

19
The categories of this paper are: eess
36
The categories of this paper are: cmp-lg
14
The categories of this paper are: math-ph
24
The categories of this paper are: dg-ga
17
The categories of this paper are: q-fin
21
The categories of this paper are: adap-org
10
The categories of this paper are: q-bio
27
The categories of this paper are: comp-gas
5
The categories of this paper are: gr-qc
22
The categories of this paper are: chao-dyn
25
The categories of this paper are: patt-sol
35
The categories of this paper are: mtrl-th
31
The categories of this paper are: ao-sci
3
The categories of this paper are: physics
7
The categories of this paper are: hep-th
37
The categories of this paper are: supr-con