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BME
Wireless Community Networks:
Motivations, Design and Business Models
Based on tutorial lectures held at Tridentcom2008
and OPAALS2008 conferences
© Cs. Szabó, K. Farkas, Z. Horvath
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Outline
BME
Introduction
Community networks
Available wireless technologies
Design considerations
Business models
Summary
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Objective of this tutorial
BME
Give an overview of requirements, services, technologies
and business models for Community Networks
From this lecture the participants are expected:
 to obtain a reasonably good understanding of the state-of-the art
technologies and the most important business models;
 to learn from experiences of some case studies;
and
 will be provided with guidelines as a starting point for the
planning of wireless CNs
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Ubiquitous access and CNs
BME
 Some historical infrastructures such as electricity networks,
road systems became ubiquitous, but
 ubiquitous access and reliability certainly cannot be taken
for granted in the case of telecommunication networks and
the Internet.
 Telecom and internet companies operate according to their
business models, the consequence is often the “digital
divide”.
 In a regional environment, however, it is possible to create
network infrastructures which, if properly designed, can
provide ubiquitous coverage and accessibility as well as the
required degree of reliability plus several more advantages.
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Introduction:
Community Networks
BME
 Infrastructure and services created with high level of involvement by a
community belonging to a specific geographic area
 Grassroot origins: “free nets”, “civic nets”
 Newer examples of community initiatives: “municipal fiber”,
“condominium fiber”
 Government initiative and governance
 Most of community networks today are driven by (local) government
initiatives, thus a definition for CN can be:
 Network infrastructure (mostly wireless), created by some form of public
participation plus
 the underlying business model plus
 the applications and services provided to communities
 related terms:
 Digital cities, digital communities (Intel), wireless cities, municipal wireless
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Outline
BME
Introduction
Community networks
Available wireless technologies
Design considerations
Business models
Summary
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A simple architectural model of CN
infrastructure
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BME
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The connectivity layer
BME
 To provide connectivity for all components (humans, organizations, agents etc.) of
the CN
 A few important concepts
 IP
 the Internet as well as most of modern telecommunication systems rely on IP,
which provides just a best-effort type service but has become THE network
protocol of current and future networks.
 Wireless
 vast majority of community networks is based on wireless technologies
 this oldest technology has become widespread during the last decade due to
advances in microwave technology, the cellular principle of network organization
and the acceptance of related standards.
 Mobility
 capability of the network to “keep track” of users that change their locations.
 Ad-hoc network
 self-configuring network consisting of mobile nodes and wireless links and form an
arbitrary topology. The nodes can be placed and are free to move randomly and
organize themselves into a network in an arbitrary fashion.
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Service provisioning platform
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SDP, Service Platform, Service Delivery Platform
A new concept that has also emerged in the telecom world
(NGN)
 change from the classic telco service model of independent,
vertically integrated networks to a new architecture that comprises
a variety of access networks and has a new horizontal layer or
platform
A set of components to deliver services through a horizontal
service network and a multiplicity of access networks.
 call control, QoS provisioning, media gateways, authentication,
authorization, and accounting (AAA)
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Applications that drive the development
of wireless community networks
BME
A) Access to public information and services
B) Public safety applications
C) Traffic control and transportation
D) Health care and telemedicine applications
E) Business services
F) Educational applications
G) Applications for utility companies (electricity, water, gas,
etc.)
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CN applications detailed (1)
BME
A) Access to public information and services
Public Internet kiosks for access to public information, tourism, portals for egovernment services and for tourists
B) Public safety
Enhancing public safety by remote surveillance of public areas
Improving the communication with police, civilian police, fire department and
the like
C) Traffic control and transportation
Coping with traffic congestion by vehicle monitoring and intelligent traffic light
control
Vehicle management for public transportation (buses)
Intelligent parking systems with flexible payment
Monitoring of road conditions, in particular in winter
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CN applications detailed (2)
BME
D) Health care
 Improving the efficiency and cost-effectiveness of health care services by
broadband and wireless communications among and within health care
providers (incl. telemedicine services)
 Home health care and assisted living
E) Business services
 Business partners/providers/clients searching
 B2B and B2C transactions
 Advertising products and services
F) Educational
 Internet access, e-learning, administration portal on the campus and extending
educational network to the home
G) Utility companies (electricity, water, gas, etc.)
 Collecting measurement data and billing information
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Wireless cities and their primary
applications












BME
Chaska, MN – Digital divide for schools, businesses and residents;
Cheyenne, WY – Traffic signal management;
Corpus Christi, TX – Automated meter reading for city-owned utilities;
Lewis&Clark County, MT – leased line replacement; access to remote county
buildings;
Medford, OR – public safety;
Ocean City, MD – Integrated digital, voice and video for city buildings;
Piraí, Brazil – Municipal field-force productivity;
Portsmouth, UK – Bus passenger information dissemination;
San Mateo, CA – Police field-force productivity improvement;
Shanghai, China – Police field-force productivity improvement;
Spokane, WA – Municipal applications and e-Government initiatives;
Westminster, UK – Video surveillance and enhanced security.
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Wireless community networks: current
status (only USA)
BME
www.muniwireless.com
City Initiatives Directory
~200 networks in “deployed” or “running” status
~180 in “in progress”, “negotiating” or “feasibility study”
status
Europe: lagging but ambitious objectives
Asia-Pacific: many similar initiatives
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Case studies (to be dealt with in detail
in the Business Models section)
BME
Wireless Philadelphia, USA
 to provide Internet access in the city, as the level of broadband
penetration is very low; subsidizing Internet access for low-income
residents
Corpus Christi, USA
 AMR application as a driving force plus other applications
T.Net – Trentino, North Italy
 cope with digital divide in the region
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Outline
BME
Introduction
Community networks
Available wireless technologies
Design considerations
Business models
Summary
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Available wireless technologies
for CNs
BME
Wi-Fi mesh
 the well known Wi-Fi (standard-based wireless LAN) combined
with the mesh network principle
WiMAX
 a relatively new standard-based wireless technology to cover
significantly larger area than a LAN – wireless MAN (metro area
network), both fixed and mobile
(Cellular mobile)
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Available wireless technologies
BME
Source: Intel Corp., Understanding Wi-Fi and WiMAX as Metro-Access Solutions, White Paper, 2004
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IEEE802.11 family of standards
BME
Standard
Frequency
range
Modulation
Compatibility
Data rate
(max.)
802.11a
5 GHz
OFDM
-
54 Mbps
802.11b
2,4 GHz
DSSS
802.11g
11 Mbps
802.11g
2,4 GHz
OFDM/DSSS
802.11b
54 Mbps
Distance
Indoor: 30-90 m
Outdoor: 100-300 m
OFDM: Orthogonal Frequency Division Multiplexing, DSSS: Direct Sequence Spread Spectrum
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New IEEE802.11 standards
BME
IEEE802.11e
 QoS (Quality of Service) enhancements for WLAN
 Already approved
IEEE802.11n
 Next generation of Wi-Fi
 Extends the maximum data rate to 248 Mbps
 Expected ratification: 2009
IEEE802.11s
 Mesh capabilities to the Wi-Fi standard
 Still to be ratified
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Wi-Fi mesh networking
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Definition
 A wireless mesh network is a peer-to-peer multi-hop wireless
network in which participant nodes connect with redundant
interconnections and cooperate with one another to route packets
 Mesh networking is an alternative to “infrastructure based”
network where there is a backbone that interconnects all nodes to
which the end users are connected
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Unwire the WLAN with mesh
BME
AP: Access Point, STA: Mobile station, SSID: Service Set Identifier
Source: W. S. Conner, J. Kruys, K. J. Kim, J. C. Zuniga, IEEE802.11s Tutorial, Dallas, 2006
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Properties of mesh networks
BME
Mesh networks are
 “Organic”, nodes may be added and deleted freely
 Fault tolerant, nodes may fail and packets will still be routed
 Manageable in a distributed way
 Of high overall capacity
Challenges
 If there are too many nodes
 If there are too few nodes
 Security
 Interoperability
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Fault tolerant property
BME
Source: Proxim Wireless, Mesh Technology Primer, Position Paper, 2005
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Fault tolerant property
BME
Source: Proxim Wireless, Mesh Technology Primer, Position Paper, 2005
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Wi-Fi mesh backbone solutions
BME
Single-radio mesh
 Each mesh node acts as AP and backbone node
 The same radio is used for access and wireless backhaul
Dual-radio mesh
 The mesh APs have separate radios for client access and backhaul
 Typical configuration: Wi-Fi local access  IEEE802.11b/g,
backhaul  IEEE802.11a
Multi-radio mesh
 Access and backhaul are separated like with dual-radio
 Multiple radios in each mesh node are dedicated to backhaul
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Single-radio mesh (IEEE802.11b/g)
BME
Source: BelAir Networks, Capacity of Wireless Mesh Networks, White Paper, 2006
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Dual-radio mesh (IEEE802.11b/g for
access, IEEE802.11a for backhaul)
BME
Source: BelAir Networks, Capacity of Wireless Mesh Networks, White Paper, 2006
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Multi-radio mesh (IEEE802.11b/g for
access, IEEE802.11a for backhaul)
BME
Source: BelAir Networks, Capacity of Wireless Mesh Networks, White Paper, 2006
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Capacity comparison of the different
Wi-Fi mesh backbone solutions
BME
Source: BelAir Networks, Capacity of Wireless Mesh Networks, White Paper, 2006
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Capacity comparison of the different
Wi-Fi mesh backbone solutions
BME
Source: BelAir Networks, Capacity of Wireless Mesh Networks, White Paper, 2006
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Limitations of IEEE802.11
standards
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IEEE802.11 standards are focused on the Physical and
MAC (Media Access Control) layers
More work is needed to define
 System interoperability
 Specific applications (e.g. Voice over IP)
 Roaming
 Core networks
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WiMAX
BME
WiMAX (Worldwide Interoperability for Microwave
Access) is an industrial forum that promotes deployment of
“Broadband Wireless Networks”
It supports IEEE802.16 family of standards
Certifies interoperability of products and technology
Global drive for acceptance of broadband wireless
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WiMAX features and advantages
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Flexible architecture
 Point-to-point, point-tomultipoint, ubiquitous
Wide area coverage
 Up to tens of km in LOS
(Line-of-Sight) environment
QoS (Quality of Service)
support
 Supports real-time data
streams
Support for mobility
 Mobile WiMAX standard
(IEEE802.16e)
NLOS (No Line-of-Sight)
operation
Easy, quick and inexpensive
deployment
High capacity and data rates
Flexibility in spectrum
 Up to 70 Mbps
allocation
High level of security
 AES and 3DES encryption
standards
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 Licensed and license-free
frequency bands
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IEEE802.16 family of standards
BME
Standard
Frequency
range
802.162004
(802.16d)
2-66 GHz
802.16e2005
(802.16e)
2-6 GHz
Modulation
Distance
Data rate
(max.)
LOS:
50 km
LOS:
70 Mbps
OFDM
OFDMA
NLOS: 8
km
NLOS:
40 Mbps
3 km
(NLOS)
15 Mbps
(NLOS)
QoS
Security
Roaming
yes
high level
no
yes
high level
yes
OFDM: Orthogonal Frequency-Division Multiplexing, OFDMA: Orthogonal Frequency-Division Multiple Access,
LOS: Line-of-Sight, NLOS: No Line-of-Sight, QoS: Quality of Service
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WiMAX applications and QoS
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Source: WiMAX Forum, Mobile WiMAX, May 2006
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Typical WiMAX network topology
BME
Source: Intel Corp., Understanding Wi-Fi and WiMAX as Metro-Access Solutions, White Paper, 2004
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Wi-Fi & WiMAX integration
BME
Source: Intel Corp., Understanding Wi-Fi and WiMAX as Metro-Access Solutions, White Paper, 2004
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WiMAX-based services
BME
Telcos carried out many pilot projects worldwide, but have
been reluctant to launch commercial services so far
First commercial operator offering mobile WiMAX-based
internet-access: Sprint
 Sprint’s XOhm service was launched just a week ago (Sep. 29,
2008) in Baltimore, USA, planning to extend it to other cities
WorldMax, The Netherlands
 currently nomadic access based on fixed WiMAX
 starting from 2H2008, more likely from 2009: mobile WiMAXbased service
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WiMAX as a viable solution for developing
countries and underserved areas
BME
 The new wireless MAN technology is a “professional” one but
suitable not only for service providers!
 Communities can deploy, too, using either licensed or unlicensed
frequency bands
 As opposed to fiber or copper based infrastructures, WiMAX requires
significantly less investment, offers high flexibility in installation
 Many non-profit, government subsidized pilot projects: Iberbanda
(Spain), India, Vietnam
 Intel co-subsidized projects:
 Parintins (Amazonia), Brazil
 Ghana
 New Zealand
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Wrap-up: Wi-Fi
BME
Benefits
 Off-the-shelf 802.11 standard
products are available
 Cost effective initial
investment
 Flexible deployment
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Challenges
 Shared bandwidth
 QoS support
 Interoperability of mesh
devices
 Security
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Wrap-up: WiMAX
BME
Benefits
 Built-in QoS support
 Built-in security
 High performance
 Standard based operation
 Flexible deployment
 Flexibility in spectrum
allocation
 Interoperability
 Integration with Wi-Fi
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Challenges
 New technology with
emerging support
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Outline
BME
Introduction
Community networks
Available wireless technologies
Design considerations
Business models
Summary
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Design objectives
BME
 Differences between planning of CNs (Community Networks), and
ISPs’ and other service providers’ design methodology
 Requirements to take into account in the planning of CNs
 Ubiquitous Wi-Fi access covering the whole territory of the community (e.g. a
city, a county or a province), no matter if some parts are sparsely populated
and/or geographically challenged
 Mobility or at least nomadic access across the covered area must be supported
 Support of a multiplicity of user devices from simple mobile phones through
PDAs and laptops to video conferencing equipment
 The network should support a specific set of government, business and societyrelated applications, accessible also from inexpensive communications services
and user interfaces
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Steps of the design process
BME
1.
Identifying applications and services

2.
Identifying network technology requirements based on the
applications

3.
Select the key applications and services which raise requirements toward the
network
Analyze the requirements of the applications and services selected in the first
step. This analysis should contain QoS (delay, jitter) and bandwidth
parameters
Identifying coverage requirements and the possibilities and
limitations of the environment

Determine the area which is supposed to be covered by the network, with its
topography, natural obstacles such as hills or trees as well as buildings,
availability of support structures, towers etc.
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Steps of the design process
BME
4.
Choosing network technology

5.
Planning of network topology

6.
Choose optimal solutions both for the access and the backbone network. This
decision should be based on the identified requirements and conditions of the
environment
Plan the network topology according to the topography and the optimal station
placement strategies using the results of the coverage requirement analysis as
well as the network technology selection
Verifying original requirements

Recognize the differences between the original requirements and the
capabilities provided by the planned network and repeat the design if
necessary
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Design process
BME
A top-down approach,
starting from
application
requirements
As opposed to building
an infrastructure first
and then see what it
can be used for…
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Technology and configuration
selection
BME
 Application requirements

We should analyze the requirements of the applications and services selected in the first
step. This analysis should contain QoS (delay, jitter) and bandwidth parameters
 Timeframe

Wi-Fi mesh is available now, however we should keep in mind that currently there is no
interoperability between different vendors’ mesh products, standard is only coming.
Fixed WiMAX is on the market, but prices will go down. Mobile WiMAX is new in the
market
 Frequency issue

In many countries or regions, mainly in Europe, it is difficult to obtain licenses required
for WiMAX. Using unlicensed ISM band can result in weak QoS and low bandwidth
because of disturbance of other devices and providers
 Costs

A careful calculation is needed for each individual project. Equipment price is not
enough to take into account (a Wi-Fi node is much less expensive than a WiMAX
station). Required density of Wi-Fi mesh nodes should be considered vs. number of
WiMAX base stations
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Technology and configuration
selection
BME
Taking into account
 Parameters defined by the relevant standards
 Calculated and measured data
 Technologies and conditions (Wi-Fi, Wi-Fi mesh, WiMAX LOS,
NLOS, WiMAX mesh)
 Availability of QoS assurance
We show
 what application scenarios the given set of
technologies/parameters can be used for
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Assumptions used
BME
 Microcell is an area covered by one access point or mesh node in the access
network. Macrocell is a union of well-connected microcells. Macrocell connects to
the backbone with one or more backbone access points
 There is no sectorization in the multimode network topology scenarios, we use only
omni-directional antennas
 Each mesh node has 4 mesh neighbors
 Wi-Fi nodes use IEEE802.11g at 54 Mbps in the physical layer
 Soft QoS means IEEE 802.11e standard in Wi-Fi. Managing QoS is one of the
inherent features in WiMAX
 The delay and jitter parameters are one-way latency measures
 Distances and cell size parameters are based on transmission power limited by EUconform regulation at high data transfer rates for high cell efficiency
 The values are mostly maximum values at optimal coverage. We can increase
maximum bandwidth density by decreasing the cell radius
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Technology and conf. selection,
capacity and coverage planning
BME
Technology
No. of
Max.
Max.
Configumicromicro-cell
macro-cell
ration
cells in
capacity
capacity
macro-cell
Max.
microcell
radius
Max.
Max.
coverage
AP dist- (macro-cell
ance
size,
0.01 km2)
Max.
bandwidth
density
(Mbps/
0.01 km2)
1
Wi-Fi
NLOS
20 Mbps
1
20 Mbps
100 m
160 m
3
7
hotspot
2
Wi-Fi
mesh
Max. 2
hops
NLOS
7 Mbps
25
175
Mbps
100 m
150 m
50
3.5
high density
coverage
(optimal)
3
Wi-Fi
mesh
Max. 4
hops
NLOS
2 Mbps
85
170
Mbps
100 m
140 m
150
1
high density
coverage with
few backb. APs
4
WiMAX
LOS
100
Mbps
1
100
Mbps
3 km
3 km
1000
0.1
rural, backhaul,
special req’s
5
WiMAX
NLOS
50 Mbps
1
50 Mbps
1 km
1 km
100
0.5
urban, suburban
6
WiMAX
mesh
Max. 2
hops
NLOS
16 Mbps
25
380
Mbps
1 km
1 km
2500
0.15
rural, urban,
suburban
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Typical usage
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Comments to the table on
technology and conf. selection
BME
 Maximum microcell capacity
 Effective usable data rate at network layer, lower than the physical data rates
defined by the given technology (decreased by 10-20% at WiMAX, 40-60% at
Wi-Fi) due to multiple access
 Maximum microcell capacity in mesh
 Effective usable data rate becomes lower due to the fact that part of the capacity
is used for forwarding
 Maximum macrocell capacity
 Max. microcell capacity multiplied by the no. of microcells
 Maximum microcell radius
 Achievable at max. transmit power and max. data rate
 It is smaller than the max. AP distance to ensure full coverage (overlapping
areas exist)
 Area unit
 0.01 sq. km is used just for convenience (an area of 100x100 m)
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Comments to the table on
technology and conf. selection
 No. of microcells in a macrocell
M
 an=1+2n(n+1); n – no. of hops
 for n=2: an= 13
 for n=4: an= 41
M M M
 No. of microcells in a
macrocell, 2-level architecture
 an=1+4n(2n+1); n – no. of hops
 Illustration for n = 3
 M – mesh node
 B – base station
 D – node with dual interface for
the connection to the B and to the
environment
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BME
M M M M M
M M M D M M M
M M M M M M M M M
M M M M M M M M M M M
M M M D M M B M M D M M M
M M M M M M M M M M M
M M M M M M M M M
M M M D M M M
M M M M M
M M M
M
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Technology and conf. selection,
QoS planning
Technology
Max.
microcell
capacity
Configuration
Average
delay per
hop (low
utilization)
Average delay
per hop (high
utilization)
without QoS
Average
delay per
hop (high
utilization)
with QoS
Bandwidth
allocation
capability
BME
Voice
transm.
capability
with/
without
soft QoS
1
Wi-Fi
NLOS
20 Mbps
5 ms
400 ms
100 ms
no
yes / no
2
Wi-Fi mesh
Max. 2 hops
NLOS
7 Mbps
10 ms
1000 ms
200 ms
no
yes / no
3
Wi-Fi mesh
Max. 4 hops
NLOS
2 Mbps
25 ms
2000 ms
400 ms
no
no / no
4
WiMAX
LOS
100 Mbps
20 ms
100 ms
50 ms
yes
yes
5
WiMAX
NLOS
50 Mbps
30 ms
150 ms
50 ms
yes
yes
6
WiMAX
mesh
Max. 2 hops
NLOS
16 Mbps
80 ms
300 ms
100 ms
yes
yes
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Combining Wi-Fi, Wi-Fi mesh
and WiMAX
BME
Wi-Fi will remain the only feasible customer access solution
for the next 2-3 years (until mobile WiMAX cards will be
as ubiquitous and cheap as expected by major players)
 Fixed WiMAX as backbone/distribution network and Wi-Fi access
from WiMAX subscriber stations
Wi-Fi is also a feasible technology to cover relatively large
areas as a distribution network in mesh topology but the
weak point is the backhaul and connecting the clusters
 Wi-Fi mesh with WiMAX backhaul and interconnection network
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Wrap-up: technology and conf.
selection in typical scenarios
BME
If some not frequently connected spots should be covered
by a wireless network, standalone Wi-Fi access points as
hotspots should be used. It can be used in LOS and, to a
limited extent, in NLOS conditions. IEEE 802.11e capable
devices should be used to support QoS requirements to realtime services such as voice communication
 Planning tables, 1st row
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Wrap-up: technology and conf.
selection in typical scenarios
BME
If a larger area has to be covered by a limited number of
backbone access points (BAPs), Wi-Fi mesh network with
only a few hops should be used. The benefits of a mesh
network are simple installation and using nodes as access
points for users and as retransmission points of the
backbone network. More than 2-3 hops to the BAP cause
degradation in effective bandwidth and also in QoS
parameters. Real-time applications can tolerate this relapse
up to 2 or 3 hops with 802.11e support
 Planning tables, 2nd and 3rd rows
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Wrap-up: technology and conf.
selection in typical scenarios
BME
Wide areas with low density of users should be covered by
WiMAX. It can be used not only in access but even in
backbone networks in point-to-point or point-to-multipoint
configuration. Robustness and high data rate of WiMAX
guarantees QoS and sufficient capacity in LOS and even in
NLOS environment.
 Planning tables, 4th and 5th rows
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Wrap-up: technology and conf.
selection in typical scenarios
BME
WiMAX can operate in mesh mode, too. In this case,
advantages of Wi-Fi mesh and WiMAX are combined. This
solution is not widely implemented yet.
 Planning tables, 6th row
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“Wireless City” design example in
Hungary
BME
Objectives
 Estimate investment costs
for several scenarios,
including a pilot network
 Create a pilot wireless CN
in a real environment
 Implement some “simple”
applications, carry out
testing and measurements
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Area to cover
BME
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Network topology
BME
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Installation costs for 3 scenarios
BME
1)
Pilot
2)
“Hot places”
3)
“Everywhere”
Qty
Price
Total
WiMAX Base Station Set
1
9,200
9,200
WiMAX-Wi-Fi Dual Node Set
3
5,040
15,120
Wi-Fi Mesh Node Set
10
2,300
23,000
Planning and installation
6,000
Total
53,200
WiMAX Base Station Set
2
9200
18,400
WiMAX-Wi-Fi Dual Node Set
10
5040
50,400
Wi-Fi Mesh Node Set
40
2300
92,000
Planning and installation
12,000
Total
172,800
WiMAX Base Station Set
3
9200
27,600
WiMAX-Wi-Fi Dual Node Set
12
5040
60,480
Wi-Fi Mesh Node Set
55
2300
126,500
Planning and installation
18,000
Total
232,580
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Outline
BME
Introduction
Community networks
Available wireless technologies
Design considerations
Business models
Summary
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Business models for a public
entity
BME
Getting the invested money back in short term is not of
primary importance, thus longer ROIs are acceptable
Maximizing the profit is not the primary objective
 There are important indirect benefits which result from aiding new
service providers, ISPs, telecom companies, value added service
providers to enter the market and grow. Hence, the public entity
can obtain additional revenues from the company taxes.
 The public sector can significantly decrease its expenses for
telecom services using the public entity’s own infrastructure.
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Basic models of public
involvement
Content, Services,
Applications,
Customer care
Customer care
Broadband networks
level of
intervention
Ducts, Masts, Poles,
Colocation sites, Dark
Fiber, Passive elements
BME
community
operated
services model
“carriers’
carrier” (active
infrastructure
model
passive
infrastructure
model
Lowest level of investment:
aggregation of demands
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Legal/regulatory issues
BME
 At government and inter-gov level: main objectives are like “Broadband services
for all” (EU)
 At regulatory level:
 Permissive type clauses in USA (Telecom Act 1996),
 A Telecom Act reform is expected to happen. Municipalities are preparing to defend
their positions. VoIP service can be one of the critical issues.
 In EU: “directives”, and the specific ruling belongs to the competence of national
regulatory bodies.
 Example: offering fibre optic infrastructure is mostly allowed (maybe not directly by
the public entity, a public enterprise such as a utility company can be a solution, in
many European countries)
 From regulatory point of view this is the preferred form (physical level or
infrastructure-based „unbundling”)
 Providing service to end-users is not advisable even if it is allowed (conflict with
market players which the public entity wants to help entering the market)
 Providing connectivity and even telephony (VoIP) service to public administration
institutions instead of leasing lines and using services from telcos
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A possible business structure
BME
LG (M)
Potential
co-owner (m)
“Infrastructure”
company
Potential
co-owner (m)
“Services”
company
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Some basic public/private models
(1)
BME
1 Publicly owned and operated
2 Privately owned and operated
3 Non-profit owned and operated
4 Publicly owned, privately operated
5 Owned and operated by a public utility
6 Privately owned and operated jointly with the municipality
The choice of the appropriate model is influenced by regulatory issues
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Some basic public/private models
(2)
BME
high
Complexity of
management
and administration
by the public entity
3 Non profit
6 Private/public
1 Public/public
5 Utility
4 Public/private
2 Private/private
high
LevelLevel
of public
of public
investment
investment
and costs
and costs
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Some statistical data on municipalities’
involvement in building and operating
wireless CNs
BME
Municipal Wireless Business Models Report, 2007
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Why municipalities build/operate their
own network?
Vezeték nélküli és mobil 2009 ősz
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72
Why municipalities do not
build/operate their own network?
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BME
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Main models and examples
BME
1) The “Wireless Philadelphia” model (“private corporate
franchise” model)
 Wireless Philadephia
 Several other wireless city projects in the USA
 Newer attempts (NSW, Australia; Fresno, CA, USA)
2) “Anchor tenant” model
 Corpus Christi, TX, USA
 Trentino, Italy
3) “Communitarian” (grassroot) models
 FON
 SparkNet, Finland
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1)
“Wireless Philadelphia”






BME
The Wireless Philadelphia initiative started with a pilot, covering the central districts
and expanded to cover the entire metropolitan area with a total 20 million USD
investment.
The project was financed and implemented by Earthlink. The business model was
based on providing Internet access in the city, as the level of broadband penetration
is very low (below 25%) and is mainly dial-up access.
Earthlink was also planning to sell bandwidth both to retail and wholesale
customers.
The city was planning to subsidize Internet access for low-income residents.
The model did not work for Earthlink and after a long period of uncertainty about
the future of Wireless Philadelphia Earthlink withdrew.
Why many Type 1 models failed or are in trouble in the USA?
 lack of commitment by the city to the service provider
 false assumptions, e.g. that free internet access can be financed by advertisements
 internet access is not enough, business applications are needed
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2)
Corpus Christi, TX, USA
BME
 The largest coastal city in Texas, with about 300,000 inhabitants and a very large
territory of suburban character
 Key application: Automated Meter Reading (AMR) system for water and gas
customers.
 The city built a pilot network covering 17 sq. miles and organized a brainstorming
with stakeholders which resulted in 20+ application ideas




building inspection (implemented)
health care: electronic health records made available on site
video surveillance
city portal (implemented)
 The city extended the network to cover a territory of 147 sq. miles
 Access point density is 60-70 per sq. miles in the center and as low as one AP per sq.
mile in suburbs.
 The city then sold the network to Earthlink
 Business model: city pays 500k/yr to Earthlink and saves 300k from AMR only.
Earthlink provides advanced internet service to citizens and hosts applications; pays
5% from its profit to city
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T.Net - the community network in the
Province of Trento, Italy
BME
• Geographically difficult, sparsely populated areas
• Poor broadband coverage by telco
• Large public sector (including e.g. health care)
• Province decided to invest in a network infrastructure
–> the T.Net project
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The Italian T.Net project (1)
BME
#Canazei
Brez #
#Pozza di Fassa
#Ronzone
Mostizzolo Revò
#Cavareno
# #
Sanzeno
Caldes
#
Cles#
#
Malè
#
Tuenno #
Dimaro
#
#Taio
Commezzadura
Ossana
#
#
#
#
Vermiglio
Denno
#Moena
Predazzo#
Cavalese
# # #Ziano di Fiemme
Tesero
#Molina di Fiemme
#
Capriana
#S. Martino di Castrozza
#Ton
Grumes #Sover
#
Mezzolombardo
#
S. Michele all'Adige#Segonzano
#
S. Antonio di Mavignola
Fai
della
Paganella
#
#
Cembra
#
Andalo
#Bedollo
Giovo
# Zambana
Pinzolo#
#
#
Lases#
Molveno#
Lavis #
#Pinè
Fornace#
Strembo#
Trento nord
Terlago #
Spiazzo#
#
Civezzano
#
Trento
S. Lorenzo in Banale
# centro
#
#Vezzano
#Pergine
Madonna di Campiglio
#
Tione #
#
Preore
#
Trento sud
#
Ponte Arche
Novaledo
#
#Lasino
Levico
#
Dro
#
#Besenello
Pieve di Bono#
#
Storo
#Fiera di Primiero
#Mezzano
Castel
# Tesino
Borgo Villa
Agnedo
# # #
Castelnuovo
Grigno
#
#
Caldonazzo
Roncone #
Condino#
Canal S. Bovo
#
Bezzecca
#
Arco
#
#Riva del Garda
#
Molina di Ledro
Volano
#
Rovereto
centro
#
#
Carbonare
#
Folgaria
#Nago
# #Rovereto z.i.
Mori
Chizzola#
Avio
#
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The Italian T.Net project (2)
BME
 T.Net - a community network project under implementation in Trentino in Northern
Italy.
 It is part of the eSociety project of the local government, whose strategic aims are:
 innovation of the local economy,
 improvement of Public Administration efficacy, and
 reduction of the gap which keeps many citizens from participating in the Information and
Knowledge Society.
 Management model: publicly controlled companies for
 implementation and management of the broadband infrastructure,
 supply of transport services, connectivity and IT services for public administration,
 renting infrastructure to market operators under fair and non-discriminatory conditions.
 The network consists of a fiber optic backbone and a pre-WiMAX-based
(HiperLAN-2) wireless access network.
 The number of backbone nodes will be 78 with the total length of optical cable over
750 km. The network will connect in total 223 municipalities.
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The Italian T.Net project (3)
Network technology
Vezeték nélküli és mobil 2009 ősz
BME
80
Creating a business model
BME
 Voice traffic, internal needs: It can be usually assumed that 40% of the traffic is internal (and
can be totally carried by the CN) and that a 20% cost cut can be achieved on the external
traffic by using the community network before reaching the external world.
 Data traffic, internal needs: On the data and information related traffic, it is reasonable to
assume a conservative scenario, where the bandwidth growth and the price reductions will
compensate each other.
 Wholesale of excess capacity: Scenarios are to be drawn up for two different types of
customers: (i) telecom operators; and (ii) business customers. It can be usually assumed that
1-2 out of the potential telecom operators and ISPs will be customers of the CN for the near
future.
 Investments: Here we need a total investment figure, the total length of the investment period
and the division of investments over that period. The model should also include depreciation
calculation for different periods.
 Financial assumptions: Include the total needed equity and its division into own equity and
external financing. The repayment conditions of external financing have to be taken into
account, too.
 Operational costs: The operational costs can be split into three main groups: Operation &
Maintenance, Personnel costs and Other costs.
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Results from a particular set of
assumptions
Profit & Acc. Profit for the BC
Cash Flow excluding financing & equity
15 000
20 000
Profit
13 447
10 000
1 362
4 900
3 279
6 518
BME
8 612
10 884
10 000
Accumulated Profit
5 000
0
2004
th. €
2005
2006
2007
2009
2008
2010
2011
2012
2013
0
th. €
-10 000
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
-5 000
-20 000
-10 000
-30 000
-29 534
-32 695
-15 000
-32 585
-40 000
Year
Vezeték nélküli és mobil 2009 ősz
-20 000
Year
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3)
Communitarian (grassroot) models
BME
 Based on sharing internet connections among the members of the community
 FON: “the largest Wi-Fi community in the world”
 FON router (La Fonera), Foneros, non-Fonero users
 Cooperation with service providers (e.g. British Telecom)
 FON communities are growing in: Geneva, Oslo, Munich, Tokyo, New York, San
Francisco
 Why FON-type models are of interest?
 failure of type 1) models in many cities in the USA
 lack of public money and/or lack of interest from commercial operators to build CN
infrastructures
 Can FON-type networks serve as CN infrastructures? Yes and no.
 for plain internet access and for applications that do not demand high bandwidth and
QoS: yes
 availability issue
 for QoS-demanding applications and services: no
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Outline
BME
Introduction
Community networks
Available wireless technologies
Design considerations
Business models
Summary
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Summary
BME
 CNs should not be technology driven
 Identifying key applications and anchor customers is critical
 The exact form of public-private cooperation/partnership depends on
 willingness and capabilities of local governments to invest and manage the
investment
 willingness of market players to become partners
 finding business models that satisfies both sides’ interests
 Technology planning includes
 selection of the most suitable wireless technology
 planning methodology for coverage and quality of service is needed
 Two key broadband wireless technologies
 Wi-Fi Mesh
 WiMAX (currently fixed, in near future mobile)
 and combinations, e. g. Wi-Fi mesh with WiMAX backbone
 Planning for coverage and QoS
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Future trends
BME
Applications
 new applications based on geospatial information systems
 example is services for tourists: accessing maps, getting directions,
finding shops, restaurants and lodging, learning about local
attractions and programs
 enabling technologies are GPS and the emerging WPS (Wi-Fi
based positioning)
Wireless technologies
 Mobile WiMAX is coming, ? if it will meet the expectations of Intel
and others
 B3G (Beyond 3G) cellular mobile systems such as LTE
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Some references
BME
 C. Szabó, I. Chlamtac and E. Bedő, "Design Considerations of Broadband
Community Networks," Proceedings of 37th Annual Hawaii Int’l Conf. on System
Sciences (CD/ROM), January 5-8, 2004, Computer Society Press, 2004. Ten pages.
 Chlamtac I., Gumaste A., Szabo C. A., Broadband Services: Business Models and
Technologies for Broadband Community Networks, Wiley, 2005.
 W. S. Conner, J. Kruys, K. J. Kim, J. C. Zuniga, IEEE802.11s Tutorial, Dallas,
2006.
 Szabó C. A., Horváth Z. and Farkas K., “Wireless Community Networks:
Motivations, Design and Business Models”. Proc. WICON07, Oct 22-24, 2007,
Austin, TX, USA. Also in: Mobile Networks and Applications, Springer, 2008.
 Proc. 2nd Annual European Congress on Wireless & Digital Cities, Cannes, 26 Sep
2007.
 F. Botto, S. Danzi, E. Salvadori, C. A. Szabo, A. Passani, “Digital Ecosystems and
the Trentino Community Network,” OPAALS (EU NoE project) report D7.2,
January 2008.
 K. Farkas, C. Szabo, Z. Horvath, „Planning of Wireless Community Networks”, in:
Handbook of Research on Telecommunications Planning and Management for
Business, Editor: In Lee, Publisher: Information Science Reference, 2008, to appear.
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