Vehicular Networks Models and Algorithms 1st Edition Andr?-Luc Beylot

Vehicular Networks Models and Algorithms 1st Edition
Andr?-Luc Beylot - Downloadable PDF 2025
https://ebookfinal.com/download/vehicular-networks-models-and-
algorithms-1st-edition-andr-luc-beylot/
Visit ebookfinal.com today to download the complete set of
ebooks or textbooks

Here are some recommended products that we believe you will be
interested in. You can click the link to download.
Vehicular Communications and Networks Architectures
Protocols Operation and Deployment 1st Edition Wai Chen
https://ebookfinal.com/download/vehicular-communications-and-networks-
architectures-protocols-operation-and-deployment-1st-edition-wai-chen/
Handbook of Sensor Networks Algorithms and Architectures
1st Edition Ivan Stojmenovic
https://ebookfinal.com/download/handbook-of-sensor-networks-
algorithms-and-architectures-1st-edition-ivan-stojmenovic/
Fundamentals of Complex Networks Models Structures and
Dynamics 1st Edition Guanrong Chen
https://ebookfinal.com/download/fundamentals-of-complex-networks-
models-structures-and-dynamics-1st-edition-guanrong-chen/
Fractal Geography 1st Edition Andr? Dauphin?
https://ebookfinal.com/download/fractal-geography-1st-edition-andr-
dauphin/

Propagation dynamics on complex networks models methods
and stability analysis 1st Edition Chen
https://ebookfinal.com/download/propagation-dynamics-on-complex-
networks-models-methods-and-stability-analysis-1st-edition-chen/
Broadband Services Business Models and Technologies for
Community Networks 1st Edition Imrich Chlamtac
https://ebookfinal.com/download/broadband-services-business-models-
and-technologies-for-community-networks-1st-edition-imrich-chlamtac/
VANET Vehicular Applications and Inter Networking
Technologies 1st Edition Hannes Hartenstein
https://ebookfinal.com/download/vanet-vehicular-applications-and-
inter-networking-technologies-1st-edition-hannes-hartenstein/
Probabilistic Models for Computer Networks Tools and
solved problems 2nd Edition Jose Alberto Hernandez
https://ebookfinal.com/download/probabilistic-models-for-computer-
networks-tools-and-solved-problems-2nd-edition-jose-alberto-hernandez/
SS Thinking and the Holocaust Andr Mineau & Andre Mineau
https://ebookfinal.com/download/ss-thinking-and-the-holocaust-andr-
mineau-andre-mineau/

Vehicular Networks Models and Algorithms 1st Edition
Andr?-Luc Beylot Digital Instant Download
Author(s): Andr?-Luc Beylot, Houda Labiod
ISBN(s): 9781848214897, 1848214898
Edition: 1
File Details: PDF, 11.85 MB
Year: 2013
Language: english

Vehicular
Networks
Models and Algorithms
Edited by
André-Luc Beylot
Houda Labiod
Series Editor
Guy Pujolle

First published 2013 in Great Britain and the United States by ISTE Ltd and John Wiley & Sons, Inc.
Apart from any fair dealing for the purposes of research or private study, or criticism or review, as
permitted under the Copyright, Designs and Patents Act 1988, this publication may only be reproduced,
stored or transmitted, in any form or by any means, with the prior permission in writing of the publishers,
or in the case of reprographic reproduction in accordance with the terms and licenses issued by the
CLA. Enquiries concerning reproduction outside these terms should be sent to the publishers at the
undermentioned address:
ISTE Ltd John Wiley & Sons, Inc.
27-37 St George’s Road 111 River Street
London SW19 4EU Hoboken, NJ 07030
UK USA
www.iste.co.uk www.wiley.com
© ISTE Ltd 2013
The rights of André-Luc Beylot and Houda Labiod to be identified as the authors of this work have been
asserted by them in accordance with the Copyright, Designs and Patents Act 1988.
Library of Congress Control Number: 2013936314
British Library Cataloguing-in-Publication Data
A CIP record for this book is available from the British Library
ISBN: 978-1-84821-489-7
Printed and bound in Great Britain by CPI Group (UK) Ltd., Croydon, Surrey CR0 4YY

Table of Contents
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . xi
Houda LABIOD and André-Luc BEYLOT
Chapter 1. Congestion Control for Safety Vehicular
Ad Hoc Networks . . . . . . . . . . . . . . . . . . . . . . . . . 1
Razvan STANICA, Emmanuel CHAPUT and André-Luc BEYLOT
1.1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2. Beaconing frequency . . . . . . . . . . . . . . . . . . . 5
1.3. Data rate . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
1.4. Transmission power. . . . . . . . . . . . . . . . . . . . 10
1.5. Minimum contention window . . . . . . . . . . . . . 12
1.6. Physical carrier sense . . . . . . . . . . . . . . . . . . 25
1.7. Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . 31
1.8. Bibliography . . . . . . . . . . . . . . . . . . . . . . . . . 32
Chapter 2. Inter-Vehicle Communication for
the Next Generation of Intelligent Transport
Systems: Trends in Geographic Ad Hoc
Routing Techniques . . . . . . . . . . . . . . . . . . . . . . 39
Xunxing DIAO, Kun-Mean MOU, Jian-Jin LI
and Haiying ZHOU
2.1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 39
2.2. IVC-relating ITS projects . . . . . . . . . . . . . . . . 42
2.3. Wireless sublayer techniques . . . . . . . . . . . . . 45

vi Vehicular Networks
2.3.1. WLAN and WPAN (up to 300 m) . . . . . . . . 45
2.3.2. Dedicated short-range communication
(up to 1 km) . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
2.3.3. Cellular networks (more than 1 km) . . . . . 49
2.3.4. Comparison. . . . . . . . . . . . . . . . . . . . . . . 50
2.4. Geographic routing techniques for VANET . . . 52
2.4.1. Features of VANET . . . . . . . . . . . . . . . . . 52
2.4.2. Localization. . . . . . . . . . . . . . . . . . . . . . . 54
2.4.3. Unicast greedy routing . . . . . . . . . . . . . . . 62
2.4.4. Geocast (multicast) routing . . . . . . . . . . . . 72
2.4.5. Delay tolerant network-based routing . . . . 75
2.4.6. Map-based routing . . . . . . . . . . . . . . . . . . 79
2.5. Conclusion and open issues . . . . . . . . . . . . . . 79
2.6. Acknowledgments . . . . . . . . . . . . . . . . . . . . . 81
2.7. Bibliography. . . . . . . . . . . . . . . . . . . . . . . . . 81
Chapter 3. CONVOY: A New Cluster-Based
Routing Protocol for Vehicular Networks. . . . . . 91
Véronique VÈQUE, Florent KAISSER, Colette JOHNEN
and Anthony BUSSON
3.1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 91
3.2. Clustering or network partitioning . . . . . . . . . 94
3.2.1. General remarks on the partitioning of
mobile ad hoc networks. . . . . . . . . . . . . . . . . . . 94
3.2.2. Controlling the number of hops . . . . . . . . . 96
3.2.3. Controlling the number of nodes . . . . . . . . 97
3.2.4. Role of the clusterhead . . . . . . . . . . . . . . . 98
3.3. Mobility-based clustering in ad hoc
vehicular networks . . . . . . . . . . . . . . . . . . . . . . . 98
3.3.1. The dynamics of vehicular
traffic in VANETs. . . . . . . . . . . . . . . . . . . . . . . 99
3.3.2. Clustering according to the lane . . . . . . . . 101
3.3.3. Clustering depending on the relative
speed between the vehicles . . . . . . . . . . . . . . . . 101
3.3.4. Clustering depending on the direction
of the movement (movement-based) . . . . . . . . . . 101
3.3.5. Clustering depending on the radio
link quality . . . . . . . . . . . . . . . . . . . . . . . . . . . 102

Table of Contents vii
3.3.6. Clustering depending on speed and
relative speed . . . . . . . . . . . . . . . . . . . . . . . . . . 103
3.3.7. Clustering depending on the position,
speed and direction . . . . . . . . . . . . . . . . . . . . . . 104
3.4. Clustering of VANETs for MAC and
transport applications . . . . . . . . . . . . . . . . . . . . . 105
3.4.1. Cluster-based MAC protocol . . . . . . . . . . . 105
3.4.2. Clustering for transport applications . . . . . 106
3.5. CONVOY: a vehicle convoy formation
protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
3.5.1. Intra-convoy communication protocol . . . . . 110
3.5.2. Convoy formation algorithm . . . . . . . . . . . 110
3.6. Assessment of the convoy formation
protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
3.6.1. Optimal parameters of the algorithm . . . . . 119
3.6.2. Distribution of the length of convoys . . . . . 120
3.6.3. Convoy stability . . . . . . . . . . . . . . . . . . . . 121
3.7. Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . 123
3.8. Bibliography . . . . . . . . . . . . . . . . . . . . . . . . . 124
Chapter 4. Complementarity between
Vehicular Networks and LTE Networks . . . . . . . 131
Guillaume RÉMY, Sidi-Mohammed SENOUCI,
François JAN and Yvon GOURHANT
4.1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 131
4.2. State of the art . . . . . . . . . . . . . . . . . . . . . . . 135
4.3. General description of the proposed
architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139
4.3.1. Network organization mechanisms
for areas completely covered by LTE . . . . . . . . . . 139
4.3.2. Network organization mechanisms for
areas that are not completely covered by LTE . . . 140
4.3.3. Information collection application:
LTE4V2X-C . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
4.3.4. Information dissemination application:
LTE4V2X-D . . . . . . . . . . . . . . . . . . . . . . . . . . . 141

viii Vehicular Networks
4.4. Detailed description of the LTE4V2X-C
protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
4.4.1. Initialization phase . . . . . . . . . . . . . . . . . 143
4.4.2. Maintenance . . . . . . . . . . . . . . . . . . . . . . 145
4.4.3. Extension for the areas not covered
by the LTE. . . . . . . . . . . . . . . . . . . . . . . . . . . . 149
4.5. A detailed description of the LTE4V2X-D
protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151
4.6. Performance evaluation. . . . . . . . . . . . . . . . . 153
4.6.1. Hypotheses . . . . . . . . . . . . . . . . . . . . . . . 153
4.6.2. The results of the simulation and their
analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156
4.6.3. Analysis of the impact of the handover. . . . 164
4.7. Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . 168
4.8. Bibliography. . . . . . . . . . . . . . . . . . . . . . . . . 169
Chapter 5. Gateway Selection Algorithms in
Vehicular Networks. . . . . . . . . . . . . . . . . . . . . . . 171
Ghayet e mouna ZHIOUA, Houda LABIOD, Nabil
TABBANE and Sami TABBANE
5.1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 171
5.2. Clustering and gateway selection in
VANET networks . . . . . . . . . . . . . . . . . . . . . . . . 173
5.2.1. Clustering in VANET networks. . . . . . . . . 173
5.2.2. Gateway selection in a clustered/
non-clustered VANET architecture. . . . . . . . . . . 177
5.2.3. Conclusions. . . . . . . . . . . . . . . . . . . . . . . 181
5.3. Gateway selection in a clustered VANET-LTE
advanced hybrid network . . . . . . . . . . . . . . . . . . 182
5.3.1. Problem statement. . . . . . . . . . . . . . . . . . 182
5.3.2. LTE-advanced standard . . . . . . . . . . . . . . 183
5.3.3. Proposed algorithm . . . . . . . . . . . . . . . . . 187
5.3.4. Conclusions. . . . . . . . . . . . . . . . . . . . . . . 204
5.4. Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . 205
5.5. Bibliography. . . . . . . . . . . . . . . . . . . . . . . . . 206
l

Table of Contents ix
Chapter 6. Synthetic Mobility Traces for
Vehicular Networking . . . . . . . . . . . . . . . . . . . . . 209
Sandesh UPPOOR, Marco FIORE and Jérôme HÄRRI
6.1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 209
6.2. Generation process . . . . . . . . . . . . . . . . . . . . 212
6.2.1. Road topology database. . . . . . . . . . . . . . . 212
6.2.2. Microscopic traffic flow description. . . . . . . 215
6.2.3. Macroscopic road traffic description . . . . . . 218
6.3. Mobility simulators . . . . . . . . . . . . . . . . . . . . 220
6.3.1. Microscopic traffic simulators . . . . . . . . . . 220
6.3.2. Mesoscopic traffic simulators. . . . . . . . . . . 221
6.3.3. Macroscopic traffic simulators . . . . . . . . . . 222
6.3.4. Interactions between simulators . . . . . . . . 223
6.4. Mobility traces . . . . . . . . . . . . . . . . . . . . . . . 226
6.4.1. Perception . . . . . . . . . . . . . . . . . . . . . . . . 227
6.4.2. Small-scale measurements . . . . . . . . . . . . 230
6.4.3. Road traffic imagery . . . . . . . . . . . . . . . . . 231
6.4.4. Roadside detectors . . . . . . . . . . . . . . . . . . 232
6.4.5. Sociodemographic surveys. . . . . . . . . . . . . 233
6.4.6. Discussion . . . . . . . . . . . . . . . . . . . . . . . . 237
6.5. Bibliography . . . . . . . . . . . . . . . . . . . . . . . . . 240
Chapter 7. Traffic Signal Control Systems and
Car-to-Car Communications . . . . . . . . . . . . . . . . 247
Mounir BOUSSEDJRA, Nitin MASLEKAR, Joseph MOUZNA
and Houda LABIOD
7.1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 247
7.2. Classification of traffic signal control systems . 249
7.2.1. Static systems . . . . . . . . . . . . . . . . . . . . . 250
7.2.2. Dynamic systems . . . . . . . . . . . . . . . . . . . 251
7.3. Traffic signal control and car-to-car
communication . . . . . . . . . . . . . . . . . . . . . . . . . . 269
7.4. Summary and conclusion . . . . . . . . . . . . . . . . 269
7.5. Bibliography . . . . . . . . . . . . . . . . . . . . . . . . . 273
List of Authors . . . . . . . . . . . . . . . . . . . . . . . . . . . 279
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 281

Introduction
Due to the technical improvements implemented by car
manufacturers, we have recently witnessed a significant
decrease in road traffic accidents in developed countries.
However, there is still considerable scope for improvement in
the field of road safety. The advancement made in wireless
communications provides numerous possibilities for offering
drivers a large panoply of interesting services in the field of
intelligent transport systems (ITS). The proposed solutions
include the possibility to enable communication directly
between vehicles or through a telecommunication
infrastructure. The first solutions are thus related to
infrastructureless communications and ad hoc networks; so
we will discuss vehicular ad hoc networks (VANETs); in
contrast, the second set of solutions comprises more
conventional communications that can use infrastructures
(general packet radio service (GPRS), universal mobile
telecommunications system (UMTS), long-term evolution
(LTE), etc.). Hybrid solutions could be involved in order to
make the best use of available resources.

xii Vehicular Networks
Therefore, from a network point of view, we see that new,
specific problems are emerging. These problems are related
not only to the particular applications implemented but also
to the heterogeneous aspect of the types of networks used.
For example, in the given context, we cannot simply apply
the proposed solutions to ad hoc networks (such as mobile ad
hoc network (MANET)). The tackled themes can be found at
the crossroads of several research communities: the
telecommunications research community and the research
community of transport systems.
In this book, we discuss several interesting and relevant
research topics related to vehicular networks, such as
congestion control, routing, clustering, interconnection
between vehicular networks and LTE/LTE advanced
networks, signal traffic control, simulation tools and mobility
trace generation.
The main objective of this book is to present the
contributions brought by each research community in their
respective fields. Finally, we have chosen a descriptive
approach to draw up exhaustive reports, to globally present
the individual author contributions, to illustrate clearly their
advantages and limitations, and to pave the way for future
research. Readers wishing to broaden their knowledge of the
technical concepts will find at the end of each chapter a set of
references and the recent publications of various authors.
Considering the diversity of the fields discussed in various
chapters, this book is structured into seven chapters.
Following the Introduction written by Houda Labiod and
André-Luc Beylot, Chapter 1 written by Razvan Stanica,
Emmanuel Chaput and André-Luc Beylot presents a state of
the art of the congestion control protocols in VANET
networks. This problem is very critical. A tendency toward
decentralized congestion control is emerging at the level of
academic research, as well as at the level of standardization,

Introduction xiii
more particularly within the European Telecommunications
Standards Institute (ETSI) where several technical
specifications have been published on this subject. Five
approaches are discussed in this chapter: the first approach
based on the adaptation of the sending frequency of beacons,
the second approach based on the increase in data
transmission flow rate (due to the use of complex
modulations), the third approach based on the transmission
power control in order to increase the channel capacity, the
fourth approach based on the reduction of the contention
window size and, finally, the fifth approach based on carrier
sensing. A performance assessment of several adaptive
mechanisms involved is presented by comparing them to the
IEEE 802.11p standard mechanism.
Chapter 2, written by Xunxing Diao, Jian-Jin Li, Kun-
Mean Mou and Haiying Zhou, focuses on the geographical
routing techniques in a pure VANET. The routing is, of
course, a basic, indispensable feature that must be supported
by every ad hoc network, including VANETs. The routing in
vehicular networks – which is different from classic IP
routing and from MANET routing – is, in particular, a
challenging problem due to the high mobility of vehicles on
the one hand and the frailty of wireless connections on the
other hand, and due to the strong constraints of the
applications as well. The chapter presents a summary of
various ITS projects related to intervehicular
communications. Wireless technologies, which are
indispensable in the design of all routing techniques, are
made available, developed and experimented by these ITS
projects, and described in detail before addressing the key
problem, that is geographical routing dedicated to VANET.
In the conclusion of this chapter, the authors sketch a list of
open questions such as security, location management,
transport layer contextual techniques and, finally, the
support of the Quality-of-Service in order to increase the
reliability and efficiency of the applications.

xiv Vehicular Networks
Chapter 3, written by Véronique Vèque, Florent Kaisser,
Colette Johnen and Anthony Busson, analyzes the forming of
clusters in vehicular networks. The authors start out from
the assumption that the VANETs by themselves cannot
implement all the applications correctly, primarily because
of their intermittent connection. They can only function in
conjunction with an infrastructure. However, if we observe
road traffic, we notice that natural groups of vehicles are
formed and the main objective then becomes to take
advantage of these geographical characteristics in order to
form clusters. The aim of clustering is to facilitate the
organization of communications and minimize their cost. The
authors then propose a hierarchical protocol called a
“convoy”, which allows the construction of stable clusters as
well as providing scalability.
Chapter 4, written by Guillaume Rémy, Sidi-Mohammed
Senouci, François Jan and Yvon Gourhant, sheds more light
on the previous chapter by focusing on the complementarity
between infrastructureless vehicular networks and LTE
networks. The idea is thus to fill in the gaps of the
infrastructure-based network coverage by using intervehicle
communications. The solution is called LTE for vehicle-to-X
communications (LTE4V2X) and has several characteristics.
A first protocol allows us to collect information and organize
the network in a centralized manner. Depending on the total
or partial coverage by the LTE network, several scenarios
are considered. A second protocol deals with the
dissemination of data toward the vehicles, uniquely either in
LTE or in multihop networks. Giving specific examples, the
authors show that their solution is powerful and it allows us
to fix, quite effectively, the gaps in coverage due to the
presence of tunnels, for example.
Chapter 5, written by Ghayet El Mouna Zhioua, Houda
Labiod, Nabil Tabbane and Sami Tabbane, discusses the
integration of VANET networks into fourth-generation

Introduction xv
mobile networks. The association between a mobile network
and a VANET network aims to improve the coverage of the
mobile network and the Quality-of-Service, while having the
possibility to resort to alternative traffic routes in case there
are any problems on the usual connections. In the first stage,
the authors give an overview of the state of the art of
clustering algorithms proposed in the relevant literature.
The gateway selection problem for the vehicle-to-
infrastructure (V2I) connection is discussed in the case of
traffic transport from the VANET network toward the
infrastructure. The authors study the proposed algorithms in
a clustered and non-clustered VANET architecture. Then,
the authors look into the problem of gateway selection from
the VANET network toward the LTE advanced network.
Chapter 6, written by Jérôme Härri, Sandesh Uppoor
and Marco Fiore, deals with the simulation of vehicular
networks. The authors present an exhaustive report on the
simulation tools used, including microscopic, macroscopic
and mesoscopic traffic simulators, as well as on the
interactions between these different simulators. The chapter
details the trace generation/mobility models used by the
network simulators aimed for the assessment of different
vehicular networks’ mechanisms; it also provides the reader
with the basic elements for successfully carrying out
simulations for these type of networks.
Chapter 7 describes the signal traffic control systems. The
authors provide a classification of the different existing
systems and a fine comparison between them. A special
emphasis is placed on the dynamic systems whose objective
is to reduce traffic jams and improve traffic flow. A new
original approach via vehicle-to-vehicle communications is
presented. The proposed control system adjusts the duration
of traffic lights by using the density information provided by
the dissemination protocols, which, in turn, use geographic
and directional clustering.

xvi Vehicular Networks
Besides presenting several relevant and very interesting
areas of research, we hope that this book will contribute to
bring a realistic global view of the evolution of VANETs. As
all the authors in this book have already pointed out, there
still remain numerous research topics to be explored.
We warmly thank the authors for their very relevant
contributions and the quality of their work, as well as the
proofreaders who had the difficult task of helping us deliver
a final version of this book.
Houda LABIOD and André-Luc BEYLOT
April 2013

Chapter 1
Congestion Control for Safety
Vehicular Ad Hoc Networks
1.1. Introduction
In the highly dynamic vehicular environment, congestion
control is essential, especially with regard to safety messages.
Although a dedicated spectrum has been allocated for
vehicular communications, the European 30 MHz Intelligent
Transportation System (ITS) band (with a possible extension
to 50 MHz) or the US 75 MHz Direct Short Range
Communication (DSRC) band still represent a scarce
resource and need efﬁcient mechanisms in order to be
optimally used under high vehicular density. In both Europe
and the US, the allocated spectrum has been divided into
10 MHz channels. From these channels, one is known as the
control channel (CCH) and it is used solely by road safety
applications. The rest of the channels, called service channels
(SCH), can be used by both safety and non-safety
applications.
Chapter written by Razvan STANICA, Emmanuel CHAPUT and André-Luc
BEYLOT.

2 Vehicular Networks
The number of proposed vehicular safety applications that
could use direct vehicle to vehicle (V2V) communication is
impressive [PAP 09]. However, at a close inspection, it can be
noted that all these applications practically use the same
information, coming from onboard sensors of neighboring
vehicles: speed, acceleration, steering angle and location.
Considering this, the standardization bodies decided to
add a supplementary layer between the applications and the
transport protocol. The role of this layer, called message
sublayer in the IEEE Wireless Access in Vehicular
Environments (WAVE) architecture and facilities layer in the
ETSI ITS terminology, is to keep an accurate image of the
surrounding environment inside every vehicle and to provide
applications with the desired information.
The facilities layer only needs two types of messages in
order to achieve these objectives, called (in the ETSI ITS
architecture) cooperative awareness message (CAM) and
decentralized environmental notification message (DENM).
CAMs are regular beacons, transmitted by every vehicle with
a predetermined frequency, and containing details about the
vehicle that might be relevant to its neighbors from a safety
point of view. In addition, if a vehicle detects a potential
hazard (e.g. a sudden brake) and considers that this
information needs to be quickly disseminated to the other
traffic participants, it transmits a DENM.
However, regardless of the scenario and message type,
these safety messages are always transmitted in broadcast
mode at the medium access control (MAC) layer. Even in the
case when the transmitted information targets a certain
geographical area (e.g. an electronic brake alarm is only of
interest to vehicles traveling in the same direction as the
transmitter and situated behind it), the message is still
broadcast and the filtering happens at the facilities layer, as
described by the ETSI framework [EUR 10].

Congestion Control 3
The broadcast nature of the CCH in vehicular ad hoc
networks (VANET) is an essential property that
distinguishes it from other IEEE 802.11-based networks. As
a matter of fact, the numerous studies on the distributed
coordination function (DCF) implementing MAC mechanisms
in IEEE 802.11 usually focus on unicast traffic, and broadcast
messages are only considered for control purposes. Oliveira et
al. [OLI 09] quantify the influence of broadcast traffic on the
performance of IEEE 802.11 networks, and they find out that
the effect of broadcast messages becomes significant when
the proportion of broadcast traffic is higher than 50%. In this
scenario, the behavior of the network largely deviates from
what is predicted by classic DCF models. However, the
authors consider this situation quite unreal and they do not
investigate the issue further.
Another important characteristic of safety messages comes
from the limited lifetime of CAMs. As these beacons are
produced periodically by the facilities layer, there is a certain
probability that they can expire before the MAC layer has the
opportunity to transmit them. When a CAM is waiting for the
IEEE 802.11 back-off timer to expire, and the next beacon
also arrives in the transmission queue, the first message has
to be dropped, as its transmission would only disseminate
outdated information to its neighbors. This property, rarely
taken into consideration in VANET studies, has a significant
effect on the optimal value of different MAC layer
parameters.
The IEEE 802.11p amendment [THE 10] is the preferred
MAC technology in both the IEEE WAVE and the ETSI ITS
architectures. IEEE 802.11p radios can communicate at a
distance of 1 km. In a simple scenario, with a two-lane road
in both directions and an average inter-vehicular distance of
50 m (a medium density highway), the number of one-hop
neighbors reaches 160 vehicles. This is clearly a more

challenging environment than the classic Wireless Local Area
Network (WLAN), with a central access point and no more
than 10–20 nodes. The MAC layer protocol, therefore, needs
solutions for this congested environment to achieve
scalability.
Congestion control mechanisms received a lot of attention
from the VANET research community and the most relevant
studies in this area are summarized later. The
standardization bodies also recognized the importance of a
decentralized congestion control framework for V2V safety
communications, and ETSI published a series of technical
specifications in this area in July 2011 [EUR 11]. In the US,
the Society of Automotive Engineers (SAE) is also developing
a standard with similar objectives, SAE J2945.1, currently in
a draft phase. SAE J2945.1 is expected to be integrated into
the WAVE architecture as a complement for the different
IEEE standards.
In this chapter, five different approaches for MAC layer
congestion control are discussed. In section 1.2, beaconing
frequency adaptation is presented that reduces the number of
transmitted safety messages in a dense network, speculating
the relationship between high density and reduced speed in
vehicular traffic. In section 1.3, increased data rates can be
achieved by using more complex modulations and result in a
lower occupancy of the CCH. Other proposals form the object
of section 1.4, which are based on the fact that transmission
power control has an important impact on the number of
hidden nodes, and can increase the spatial reuse and hence
the channel capacity, in a congested network. In section 1.5,
the fourth element, the minimum contention window
(CWmin), is analyzed, a parameter with a major importance
for collision probability in an IEEE 802.11 network. Finally,
the role of the physical carrier sense in congestion control is
highlighted in section 1.6.

Congestion Control 5
1.2. Beaconing frequency
The most obvious solution for controlling the channel load
in a congested environment is to reduce the number of
transmitted messages. This can be achieved in a
straightforward manner in vehicular networks by adapting
the frequency of the safety beaconing. However, such an
adaptive mechanism should be designed carefully because
sending less messages can easily have the effect of damaging
the performance of safety applications instead of improving
it.
In this context, Fukui et al. [FUK 02] proposed
transmitting a CAM every time the vehicle travels a certain
distance instead of using a regular time interval. According
to a fundamental relationship from traffic theory, the mean
speed decreases when the vehicular density increases, thus
the consequence of this approach would be that nodes would
reduce the beaconing frequency in a dense network where
they would travel at low speeds. However, a basic example for
which this solution fails is that of a vehicle waiting to make a
left turn in normal traffic. Because the vehicle would need to
stop, the adaptive mechanism would practically turn off the
beaconing transmission, making an application like the left
turn assistant practically unusable. Therefore, as stationary
vehicles or low speeds are not always the consequences of
high vehicular densities, such an approach cannot be
efficiently used in a real scenario.
As a part of the California PATH program, Rezaei et al.
[REZ 07] take a more complex approach, where vehicles run
an estimator to calculate the position of each one-hop
neighbor based on the already received messages. The same
estimator is used by the node to predict its own position, as it
would be calculated by its neighbors. When the difference
between the prediction and the actual location becomes
larger than a predefined threshold, the node transmits a

safety beacon. The problem with this solution is that it is
efficient in the predictable free-flow traffic, but not in a
congested scenario where the acceleration is highly variable.
Moreover, this self-estimator approach does not take into
account that the error at some of the neighbors might be
considerably different because some of the transmitted
beacons could be lost. To solve this problem, Huang et al.
[HUA 10] further develop this idea using the packet error
ratio (PER) measured by a node to predict the losses
encountered by its neighbors. Still, measuring a PER in a
vehicular network without being able to detect collisions or
use feedback from the receivers is not a straightforward task.
Seo et al. [SEO 10] make an analogy between the safety
beaconing and the coupon collector problem. The mechanism
they design relies upon nodes piggybacking acknowledgments
(ACKs) for the received beacons in their own safety message.
Every received ACK would further delay the transmission of
the next CAM, reducing the beaconing frequency. However,
the introduced overhead would be significant, especially in a
dense network (a 4 byte ACK for 50 one-hop neighbors would
result in 200 extra bytes for every safety message). It is also
unclear if this approach would be compatible with a security
framework based on changing pseudonyms, like the approach
currently proposed by the ETSI ITS architecture [PAP 08],
because the ACK would need to include the identifier of the
sender and most probably a sequence number for the
acknowledged message.
Adaptive Traffic Beacon (ATB) is a solution/mechanism/
approach proposed by Sommer et al. [SOM 11], where the
beaconing frequency is calculated based on two metrics: the
channel quality and the message utility. The idea is to
transmit only the most important messages in a congested
network, reducing the offered load. Nevertheless, the channel
quality is very sensitive to the number of collisions, which
implies that the nodes are somehow supposed to detect such

Another Random Scribd Document
with Unrelated Content

Til K I N hi A N COIN THY. 1W •PI" XT UlWIl llVt'l'. 'riii'sc
I'lii'liiiliiiciits (if (licir j;«M>jrrii|»liiciil iiivii wt'U' jiivcftU'il li_y ('ti'n.«i
(' (liHtiirliiinci'H in iju- iiortli. 'riif vi'iir JS.lL' viis marki'il liy i. luistilc
coiiiliiiiatinu ol' several of tlie leadlnu trilies (if llie r|(|>er Missisiiiiiii
ami the Lakes. 'I'lie Sac iliief, Hlack Hawk, eoiiiiiieiiied his war. 'I'he
(lilH.s aiijaceiit to llie Sai-M ami JMixe.s hs nipalhi/.i il with the latter
in the husliiities, wiliuMit openly funwii into the contest. ISy
inslinctions eai'ly issudl, ami a;:enls despatched into the distinlKil
districts, the government reachcil and checked a jirowinff
comliination on the I'pper Mississippi. Meinjr si'lccted as oni- ol"
these a^icnts. and provided with the means of oliservation. as well
as military protection, I piisiied these discoveries nortii to the actnal
source ol' tiie Mississippi, in Itasca Lake.' Lieutenant .Lnncs Allen, I'.
S. A., I'lniiished an authentiir map of the river, as the residt of these
explorations, from the point at whii ii the search had heen ilropped
in IS'H). 'I'he usual results liiliowcd this ill-advi.sed project of IMack
Hawk. He was ovcrpiiwei'ed and made c'lplivc, with ids ailhcrcnts,
late in tiie fall of the siune year; and liniiself and his frienils sulli'rcd
llie |ienal(y of altemiilinji- to deny or ainnd a prior treaty, l»y the
necessity they laouuhl theuiseKi-s under, of makinu' new
concessions. Sis years of a slate of peace followed this wai", durinir
which, the profrress of white population fi'om llie east to the we-t
lielokeiieil I'apid and etensivi' (dum^rcs ; and the trik's made
iiicipieni arraiejcmeiils lo surrender their line on the .Mississippi,
helnw the Iowa river. Wisconsin and Iowa lieiian rapidly to sissnme
slrenuth. In lS;iU. surveyoi's were

1!M» I'M YS IC A I. <: KiMi II A I'll Y l»K l> V A V oiiiilli (il
LaUf Sii|H'iiiir, uliiili liail Iktii |iiir('lia^<'il in l>>'ii'>. cr*> |iiit in a
niin'M' iil'.«ni'f, wliicli wmh cntin^tril In llic IimikU oI' Dr. |>i)ii;;laK
lloiiiilitoii, w III) liMil Ix'i'ii p'(il(i;;i!«t ami lintani^t Id iIh* i'|H'i|iiiiin
In Ita-ca, in Is.'h. Siilisi')|ii<'iitly, tlic tract.') |ini'<'lia.''i'il at Laixiinli-.
in Isl'J, wi n- ui'ilci'til tn Im> .Hnrcvcil. and finnniitti'il til tlif ilii'i'i'litiii
of Dr. iFa(lMiii. .Mr. A^ja.-.î/, i>il('il llic liarf Imivc imliirctlv irinn
liini. tiliM-rvatiniis on tlu' ctiiirxcs anil intrn>'it_v «>!' till- Miji'aiiii-
i'ni|itiiiiH wliirli Iimm- rmn iiImmI. at an anriiiit I'ra, this iiiti'n>tin>r
ininI'lal ami i;;m'on.s rcîioii. 'riu'.sf snrst'vs ami p'oiniiiral
nlpscrvatinns liavr lirm Milisfniu'iitlv rontiniuil. Miiu'c the iliatli of the
lainrnlril Dr. Ilnii::lilun. i I'liailcs Wiiitlliv^v . Kmj.. ami l> Dr. .1. (i.
Norwiiiiil ; ' ami liii'V ari' ol' liiL'li valm- to all wlio tli'sirt- to ai'i|iiiri'
just vit'WMol' till' ^rolo;:ii'al |ili('ni>iiit'na uiiiili an- l>i'i>ii;:lit into
ili>i'ii>îoii. In tlii.s inaiiiu'r tin' lioininion-* of M'icm'c Inni' licrii
cvtt'mlcil towards tlic iiortli ami M'.«t. and wt' liiiM' liicoiiK'
a((|naint('d with thi' ^colojriral .xtiMctnrt'. |irodiutions. and xalnc lit'
the iinnicn>c lim* of interior ti'ans-.Mississi|i|iian Indian i'onntr .
Still we hai' no |irrri>î' inliirniatioii that ii'ai'lu'.s lifoml tlu' liordi'i's
of I.aki' Su|i('rior. iinrlli ol' a line I'MfMdin'.: wr.-t from its lirad. across
the Mississipiii iit the < PI' n iww n I.: rixcr, to tiic iianl^s of llnl
Itivcrof the North, and ciiiliiacinv the vast annlc of aralilc couiiliy.
dihnial drill, and U'll-rucU, oxtcndinj;' to .. latitmk' 111 . pns.se.sscd
liy the l'hi|>|ica nation. I am imhii'i'd. Ii this idea, to iiialllo and
iMMl. and res|ieclin^' liicli. some leadiii'/ ]ioints in its ireop^ripliy
had Ih'cii at tiiat time lel'l indeteriiiinate. canmit Imt excite continned
inteivsf and curiosity. In jiiiieraii/iiiir the fads oliscrvcd in so wide a
field, it must lie locollecled that the cNpeditiuii had ini|)i)rtant oliji'cts
relatinii to the |iolicy. numliers. and feelinjis of tlin Indian trilx's. (o
wliicli (|iiestioiis of this kind were liirced to 'Aw way; that the transit
over the country was necessarily rapid ; and that few iipportniiities
of elaliorate or I continued oh.H'rvations occurred on the route. The
;:eoloi.dst must ofti'ii sieze his fact.s with rajiidity. ami although he
may carry with him materials for irencrali/ation. he is compelled, in
hasty recoumiis.«aiicis. to rely freipiently upon hrirf exainiiiations for

his kiiowledjit' of locks, soils, displacemeiils and outcrops, the
incliiiatiuii and juxtaposition of strata. >.*i;i'. Il-prciaily i- thi- the
case in passinj; tliron^jrli such ji Ollii 'Owen's ('nnv,irhl;itii| lli'|H.rl i.f
l».>J i

Til K I N hi N rnl NTU V I'.'l foiiiilrv iix liii'* U-fii visited, uinl
in i-vpioriiii; u rt^'imi wliiili i^. ('iii|ili!ili('iill . a uilijii'iii'M>>. The
iiiiiiii'iioi' i-ii'iitir liltM'k-liiniiatinii at iIh- r«iiii'fi- of llif .Mi~->i<>i|i|ii.
ami tlic iifn iiiaiiiH- tiiil't llial liimix, a* it wcif. a iiiaiitlc tu lln'
rnik-!>tiala. illi rliiallv |iif. viit iilioi'i'vatioM, I'MTjil at «lri'|i nitliii}."* "i"
^trcamt ainl cirlailifil |HiiiilH. Sinli iiitiiiiiil' olimTxatioii a< I hail, I
have |irr><<'i'M'il in iiiv nii'iiioniiiilM ; anil in my rrritllt'clinn-*
|ianiirama nl' 'I'mi'" a ml liirniatiiins. which con^titiili' a nin>l iiitri'i-
lim: am! iiiaL'iiili fciit line 111' lake anliyrinj: iVuni vniianic aetinn. at.
ami ma'th of. the chain nt'the (ireal lell rather the eviilence III' ili-
rnplioiis ami npheaals nf rni-maliiin". which <:i(> its mitthern
ciia>'t>'. tu M>me extent, the charaeler i>r er ancient tiieatre-i nf
nlcanic acliiin. These lakes. eNcept (hitai'ili aiiiie Kinirston ami lirie.
inilicale the hnumlaries lulween the piiniitie ami KeeomlaiT strata.'
Itnl hnweer sliikini; the fact til' this .■.epaiatinn niii_ appear at
paiticniar lucalitirs. -ni li as on the Straits ol' ."^1. .Marv.iil' whii'h the
ea-t ami wot shores are. at inii>l pai'ts. M-culo'jically ol'tlinerent
I'onsti'nclion. ^el notliim; in the uianil piienouh'lia ol' the w I II lie
re;; ion isileil. is so Tell la rival lie a» I lie liiilllijer or erratic Muckst
rat inn. which is spread i;enei'ally Iroin the hi,:;hesl lalitndes nl' ijn'
iiorlli. lo thee ulilie south. Some of the li|oc!s nl' rock are enormons.
and wonld seem to dcfv an kn< power of renioal {'rmn their
parent l)ed<. The lar;:e>t nl" the>e lilucks have the most iliscnn-
maiks (if attrition, (tilin- Imse had their ai mplcielv renioM i'.v 111
the ^'reatcr nnmlier ol' tin se traii-porled lionlders are ipiile .-muoih
and roniided li the liiree ol' attrition, 'i'his drii'i-siralnni has heen
I'orceil and scattered rioin its nortlnrn lalilmli's. over the .-nrlace ol'
liie linu-tones. sandstones, anis .iidaloids. and trap-rocks ol' the
F.akes. It i- mixed projii-elv with thi'dilnial mmIs ol' .Michiiian and
Illinois; lint il is e iileni I lial. in il» di-per>ion .-■ nlll. the hea ie-l
piece- ha e sell Id lir-l. lliie comparalivelv niinnte hoidders hat'
heen carried iner or spread in the plains ;iiid prairies of <>hio.
southern Illinois, nnd Indiana, and mine sonllieridy re;:ioiis. '•
Noliods'. with an i'i' to its i;eolii!;-. oan ini-take the lieavv Imnlder
deposits. >hich mark the Minthern .-liores of llnrnn. and liecnme still

more !iii nndant in tin alle of the Si. .Mar's. on th e snores ol Lak
nperior. and aionu llie foamiii;.' I'hamuds of the St. l-e masse' Tlii'.v
liiiiis an' 11'iw .-iiiHrMMli'il. Tin' iMrk> ili. im il rr)>lalliiic arc iidw
ri'giirJoii us igmnii.-, uikI iln .-iliiri B'rjla ciiibrares all (lie ilJiT .-
coiiiilarv, Imt ii"iii' of tlio iRWot.

V>2 r 11 Y s 1 c A L (.; !•; < k; ii a v ii v u i" rcMcliiim to
inoiiiitaiii altitudes, lu'tworii (In- Clmcdlali' and Huron livi'is ol" tliis
ooaft, arc n'-aii|ii'aranct'.x of tlu' rliain of priniarv rocks wliicli
tcrniinati* at (!ros I'oint, at llic north capo of St. Clary's livci'. After
passinu; under tlic .-andstoncs of I'oint ]ro(|uoi.-i; — the
Ta(|U!iini'noii ImiUm ; — tlic !-andy tracts .xtivtiliiniz iVoni Whitc-lish
IViint ; — the strikini.' elevations of the frreat sand-dnnes of tlie
(Irand Maiais. and tlie ch ated coa-ls of the J'ictnred IJocks.
reaidiing (|nite to Carp and Cliocolate rivers, they rise in the (Jranite
IViint Mountains, in conical peaks, which characteri/.o tiie Supciior
shores, near Aiipo Kewooiia. Continuiujr west, we next havi' the trap
st'ries. willi their copiicr veins, which stretch westward to. and
lieyond. Montreal rii'r. till they onco more arise in the granitic series
lyinir west of the liay of St. Cinirles. I.apointe island, and Cranheri'v
river. Still loUowinj:' the primitive development west and north-'vest,
uni ler th u' sandstone elevations of the .M usKe"o or 15ad river, the
NamakaL;on. the St. Croix and Hum rivers, they re-appear, with tin'
sami' shininu and crystalline character, and till' same sjiarseness of
mica in tlicii- constitution, until reachinji the Mississi|)p' jiver. wiiich
the cross alR)ve St. Anlhon"s Kails. Ix'iween the Sauk and De
Corbe ui risers. "St. Anthony's Kails, a iew of which is i;icii in IMati'
liS. are upon and o.cr the saiidstttne strata which are oxerlaid, on
the shores tl le me tali ili'rous and carlionif'l'ous series. Tliis st'i'ies
rests upon and ai;.iiiiippi. at these falls, drops, in fad, into a valley,
whose sides loriii si'ries of ])ictures(pu' clilVs. emliiaciim widi-r and
wider tracts of the most fertile bottom land, till the' reach near to
the mouth of the Ohio ; — the CaM'-iu-ltock knobs, ami the clill's of
the (Irand T owcr and the .Missouri shore. These form the very
expandi'd ircoloiiical jaws throuvdi whii'li the river pours its waters
into its vast diluvial reirion. constituting !hat Nilotic delta of which
the Hali/e marks its ixtremc ju-otrnsioii into the (lull" of -Mi'xico. Not
less than three thousand miles arc reipiired for the display anil
evolutions of this river; and wln'ii we revert to its source, it is found
to be on a contiiu'iital summit of less than ei.iihti'i'ii hundred leet
elevation al)ovo the Atlantic. This summit is formed liy an ni>heaval

of the crystallino id trap rocks which Hir 111 siu h St riKiu':' (iisiiia in
th le basin of I<;ike Sujierior. K O K l A r 1 II N A T T II i; So I i; r i;
n I' I II i: .M I I S > I 1' I' I . Ill Older to coiupreheiid the p'oloiiy of
this reuioii. it is necessary to [iremise. that Ins CI inlincntal elevation
of the granitic series. moiU'r.iti as It 1.lears a lieavv ma.ss of drift
strata, all of which are the material of pre-existing and broken-down
iiirmations. TIie.>'e appear to have been ehielly sandstones, slates,
schistose rocks, amygdaloids, and traiis; the latter of which liavi'
existed in vast dykes in the iniderl III'.;' ramies. eonformably to the
ssstein exhiliited in the basin of l-ake Super lor. ('ide (jeol. Map,
herewith.)

m^ =«;%» i5 ' i 'n fi;|i i i'i !ll: 'Kfi

I f :t-i r ■ i : ; n m ill r ■ i

Tin: INDIAN fM)i:NTUY. m "TliiH hc'i};lit of liiiul Ix-jriiis
imnuMlititcly west of tlic liiisiii ami river of tlio naiiiy Tiuki'. It
Hubti'iuls till' utmost whiici-h of tlic AMississipiii, nml n'lirlit's to tlic
mmiiiiit, mill coiitiiuH's soiitli. of Ottcrtail Ijnko, where it ilivide.s the
utmost trihiitaries of tho Ked Kiver of the North from those of tlii'
Corljeaii. or Ciow-wiiif,' river, and the river St. Louis of Tiake Superior.
Tiiis elevated raiijre serves to condense the vapors of the
surrounding; waters. The drift serves as an aihiiiratilo filter li)r this
moisture, whieli is finally arrested hy vast lieds of clay, resiiltiiif; from
the eommintiti'd ehiyslates and schists. To these eanses of watery
accumulation, an- ailded the usual rains and snows. The ellect has
U'l'ii, that the Miiiunnt of thi'se couileiised and atmospheric wmrces
of moisture, sinking into the sandy luils till tiiey are arresteil hy the
arj;illaeeous sulvsoil. pours out, iii crystal streams and sprinjis. on all
sides. It acts, therefore, as the primary water-shed, nut only Hir the
iMississipi)i and the Hed liiver of Jiiidson's Hay, imt is not a small
.smrce of supply for the j;reat lakes and the Niajiara, and through it,
for the Gulf of St. Lawrence. 15 A s I N (I r Ti A K i: M k ii i r; a n .
'•Tiiis hasin stretches ahout three hundred and fifty miles, from
north to south. It is deeply seated in the lake liirmation vi'
sandstones, limestones, and schists, incluilinji' prohahly the northern
edjic of t!ie coal strata. The piles of huri/.oiital compact limestone at
the entrance of (ireeii Iiay ; — the solid beds of tertiary clay of
Mihvaukie; — ami the hleak saiid-dum-s on its eastern shores,
extending!', with intervals, from the Konomik to the coast opposite
the Manito i.sles, constitute very striking features. At ChieajLto the
wide and level piaiiie diluvioii of the Mississippi valley comes (piite to
the shores of the lake, formiiiu its southern maijiin. and di'vi'lopiiiii' a
striking [>oiiit of union of the great lake and jjrairie sstems. The
sketch of this s[)ot, Plate li7, is drawn Irom a view taki'ii on the
arrial. at that place, of the expedition. It exhihits Fort Dearhorn, as
it then stooil, the house of .Mr. Kinzie, the patriarch of the [ilace, the
I'liited Indian Agency and shops, and the dwellings of a lew traders
and residents, who comi>rised the i)oi)ulalion ol' the hamlet." C II
IJ'I'K w A Cui.o V. In siihmitting these remarks on the lake hasiiis

and the region at the sources of the Mi.-^sissippi, occu[)ied hy the
('hi|)pewas, it may he added, that the latter allords every desirable
recpiisite for a colony of ret'uge for that nation. The niimher of its
lakes enables the Indians to supply themselves with fish, which are
(|uite abundant in all the larger basins of transparent waters in these
regions. The numerous streams by which it is intersected, are scenes
of great attraction for water-fowl. They also still aflbrd, in moderate
ijuautities, the small furred animals, whose skins are .«ouglit. Must
Pt. IV. — 1>3 i 'i' I, ■; ■! I f " w 1 m y 1

I i; l!t4 PHYSICAL GEOnilAl'IlY, ETf "f tlif lakfs. imlri'(l all of
tlu'iii wIioho watfis an- shallow, afl'onl tlic s|uci('s of native iici« oil
which this Irihehassolonj,' ivlii'd. And iiotwithstaiitliiij; tlii-
lai';;i'sithafi('iioiisaiiil worthU'ss tracts in soiiio districts, and arid
riilgcs of mind, or hard gravel and Kami, ill others, tiic proportion of
fortilo soil, which, in its natural state, fields maple, elm, and other
hard W(K)d species, far exceeds these i>ad tracts. .Maple-sii;.'ar is
the product of evi'ry consideralile district ; and tliis item, with its
jiaiiie. completes the list of the reliances of tlio Indians while they
are in a hiiiiter state. And they must contiime to lie I'ver desiraljio
resonrces to tlieiii, while they go tliroiij;li the incipient stages of
agriculture, anil until they can fully and Iioldly rely on the latti-r. lii
addition to this, it is a region covered with forests, and thereliuv will
long su|)ply them leiicing and fuel. The laI)or of digging wells is not
reipiired, as running streams and small lakes are so aliundaut as to
su))i)ly their settlements with water until they U'come (piite dcn.se.
Alxive all, it is eminently healthful, and its climatic phenomena of
spring, summer, and winti'i'. are .such as to commend the ri'gioii
strongly to their approliation, haiiits, and manners. Assnniing the
Chippewa population now thi'ie, or which is due to the region hy
existing treaties, at 7t>(l<*, the area is most amiile, and, indeed,
suitable liir a large colony. The Iioundary of an Indian colony, in this
(piarter. might Ih- includi'd in a line ruuuiug south I'ldiu the parallel
of lU", ,so as to strike the outlet of lied liake ; to lii' continued till it
reaches the outlet of Ottertail Lake; thenco due east to the
Mi.ssissij)pi river, following its channel upwards to the Falls of
Puckaguma; thence due north to the national boundary. This would
create a compact and shajiely territory, avoiding the intermediate
valley of IJed river, hut securing all the upper [)arts of the iillliients
to it. It might, under certain conditions, be made to include the
entire area east of the Mississipj)!, to the liritish j)ossessions on the
IJainy Lake boundary ; embracing the mineral coasts t)f Lake
Superior, and thus Ix'conie an a]ii)endago to the commerciiil syHtom
of that interior ocean.

V. TRILAL ORGANIZATION, HISTORY, AND GOVERNMENT.
D, [Itii l»Ari:ii. Tni.i; V.] (lor.) m i. t ili si 1 1 11 mi

Welcome to our website – the ideal destination for book lovers and
knowledge seekers. With a mission to inspire endlessly, we offer a
vast collection of books, ranging from classic literary works to
specialized publications, self-development books, and children's
literature. Each book is a new journey of discovery, expanding
knowledge and enriching the soul of the reade
Our website is not just a platform for buying books, but a bridge
connecting readers to the timeless values of culture and wisdom. With
an elegant, user-friendly interface and an intelligent search system,
we are committed to providing a quick and convenient shopping
experience. Additionally, our special promotions and home delivery
services ensure that you save time and fully enjoy the joy of reading.
Let us accompany you on the journey of exploring knowledge and
personal growth!
ebookfinal.com

Vehicular Networks Models and Algorithms 1st Edition Andr?-Luc Beylot

More Related Content

Similar to Vehicular Networks Models and Algorithms 1st Edition Andr?-Luc Beylot (20)

Recently uploaded (20)

Vehicular Networks Models and Algorithms 1st Edition Andr?-Luc Beylot