![](https://csdnimg.cn/release/download_crawler_static/18149111/bg1.jpg)
Ad Hoc Networks 55 (2017) 87–96
Contents lists available at ScienceDirect
Ad Hoc Networks
journal homepage: www.elsevier.com/locate/adhoc
Analysis of event-driven warning message propagation in Vehicular
Ad Hoc Networks
Huan Zhou
a
, Shouzhi Xu
a
, Dong Ren
a
, Chungming Huang
b
, Heng Zhang
c , ∗
a
College of Computer and Information Technology, China Three Gorges University, Yichang, China
b
Department of Computer Science and Information Engineering, National Cheng Kung University, Taiwan
c
School of Science, Huaihai Institute of Technology, Lianyungang, China
a r t i c l e i n f o
Article history:
Received 26 March 2016
Revised 18 August 2016
Accepted 21 September 2016
Available online 21 October 2016
Keywords:
Vehicular Ad Hoc Networks
Broadcast protocol
Event-driven warning messages
Message lifetime
Delivery probability
a b s t r a c t
In order to increase the probability of delivering warning messages to all vehicles (or nodes) in the Zone
Of Relevance (ZOR), Vehicular Ad Hoc Networks (VANETs) adopt the periodical broadcast to disseminate
warning messages. The broadcast way brings the problem of how to set the suitable message lifetime
for the propagation of the warning message. To tackle the aforementioned problem, this work adopts
the following four steps to analyze the event-driven warning message propagation process and suggest
a suitable message lifetime for the Vehicle-to-Vehicle (V2V) network. At first, an analytical model was
proposed to investigate the event-driven warning message propagation process in a connected network,
and thus assure that it is difficult to guarantee all nodes in the ZOR being in the same partition. Next,
an analytical model was proposed to investigate the event-driven warning message propagation process
in a partitioned network, and then the probability of delivering warning messages to all nodes in the
ZOR for different traffic conditions is derived. Furthermore, to reduce redundancy caused by multi-hop
broadcast, an direction-aware broadcast protocol was proposed for the partitioned network according to
the proposed analytical models. At last, the impact of traffic characteristics on the setting of the suitable
message lifetime was evaluated through numerical and simulation results. The results shown that the
warning message propagation process depends on the traffic characteristics, e.g., nodes’ density, nodes’
speed and the dangerous time. The results also shown that when the message lifetime increases to cer-
tain values for different traffic conditions, the delivery probability is not increased, but just consuming
power and causing serious redundancy. As a result, the work shown that the suitable message lifetime
should be set according to the traffic condition of involved nodes.
©2016 Elsevier B.V. All rights reserved.
1. Introduction
Vehicular Ad Hoc Networks(VANETs) have attracted the atten-
tion of many researchers, for the potential of providing differ-
ent applications, such as vehicle safety-related services, vehicle
driver assistance services, entertainment services and so on [1–4] .
VANETs mainly include three types: (1) a pure wireless Vehicle-to-
Vehicle (V2V) network, (2) Vehicle-to-Infrastructure (V2I), and (3)
a hybrid V2V communication and the V2I communication. VANETs
try to make the transportation network more secure, efficient, en-
vironmentally friendly and comfortable [5,6] . This work concen-
trates on the investigation of the V2V network, in which nodes can
∗
Corresponding author.
E-mail addresses: zhouhuan117@gmail.com (H. Zhou), ezhangheng@gmail.com
(H. Zhang).
form a self-organized network and messages can be directly prop-
agated among nodes in a multi-hop way.
The main motivation for the deployment of VANETs is to have
safety-related applications. For example, by collecting up-to-date
information about the status of the road, a driver assistance system
can quickly detect potentially dangerous situations, and notify the
driver about the approaching danger. A relatively small reduction
in the driver’s reaction time may potentially avoid the trigger of an
accident. VANETs thus have the potential of increasing safety level
on the road [7] . This work concentrates on investigating a spe-
cific safety application: called event-driven warning message dis-
semination [8–11] . A vehicle is defined as the source node when
it detects some danger, e.g., obstacle, bad weather, malfunctioning
of the braking system, on the road and then generates a warning
message. The warning message should be delivered to all nodes
in the area exposed to the potential danger as quickly as possible,
for which the area is called Zone Of Relevance (ZOR). The ZOR is
http://dx.doi.org/10.1016/j.adhoc.2016.09.018
1570-8705/© 2016 Elsevier B.V. All rights reserved.