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Alternative Network Deployments: Taxonomy, Characterization, Technologies, and Architectures
RFC 7962

Document Type RFC - Informational (August 2016)
Authors Jose Saldana , Andres Arcia-Moret , Bart Braem , Ermanno Pietrosemoli , Arjuna Sathiaseelan , Marco Zennaro
Last updated 2018-12-20
RFC stream Internet Research Task Force (IRTF)
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RFC 7962
Internet Research Task Force (IRTF)                      J. Saldana, Ed.
Request for Comments: 7962                        University of Zaragoza
Category: Informational                                   A. Arcia-Moret
ISSN: 2070-1721                                  University of Cambridge
                                                                B. Braem
                                                         E. Pietrosemoli
                                                    The Abdus Salam ICTP
                                                         A. Sathiaseelan
                                                 University of Cambridge
                                                              M. Zennaro
                                                    The Abdus Salam ICTP
                                                             August 2016

                    Alternative Network Deployments:
      Taxonomy, Characterization, Technologies, and Architectures


   This document presents a taxonomy of a set of "Alternative Network
   Deployments" that emerged in the last decade with the aim of bringing
   Internet connectivity to people or providing a local communication
   infrastructure to serve various complementary needs and objectives.
   They employ architectures and topologies different from those of
   mainstream networks and rely on alternative governance and business

   The document also surveys the technologies deployed in these
   networks, and their differing architectural characteristics,
   including a set of definitions and shared properties.

   The classification considers models such as Community Networks,
   Wireless Internet Service Providers (WISPs), networks owned by
   individuals but leased out to network operators who use them as a
   low-cost medium to reach the underserved population, networks that
   provide connectivity by sharing wireless resources of the users, and
   rural utility cooperatives.

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Status of This Memo

   This document is not an Internet Standards Track specification; it is
   published for informational purposes.

   This document is a product of the Internet Research Task Force
   (IRTF).  The IRTF publishes the results of Internet-related research
   and development activities.  These results might not be suitable for
   deployment.  This RFC represents the consensus of the Global Access
   to the Internet for All Research Group of the Internet Research Task
   Force (IRTF).  Documents approved for publication by the IRSG are not
   a candidate for any level of Internet Standard; see Section 2 of RFC

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at

Copyright Notice

   Copyright (c) 2016 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   ( in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.

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Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   4
     1.1.  Mainstream Networks . . . . . . . . . . . . . . . . . . .   5
     1.2.  Alternative Networks  . . . . . . . . . . . . . . . . . .   5
   2.  Terms Used in This Document . . . . . . . . . . . . . . . . .   5
   3.  Scenarios Where Alternative Networks Are Deployed . . . . . .   7
     3.1.  Urban vs. Rural Areas . . . . . . . . . . . . . . . . . .   8
     3.2.  Topology Patterns Followed by Alternative Networks  . . .   9
   4.  Classification Criteria . . . . . . . . . . . . . . . . . . .  10
     4.1.  Entity behind the Network . . . . . . . . . . . . . . . .  10
     4.2.  Purpose . . . . . . . . . . . . . . . . . . . . . . . . .  10
     4.3.  Governance and Sustainability Model . . . . . . . . . . .  12
     4.4.  Technologies Employed . . . . . . . . . . . . . . . . . .  12
     4.5.  Typical Scenarios . . . . . . . . . . . . . . . . . . . .  13
   5.  Classification of Alternative Networks  . . . . . . . . . . .  13
     5.1.  Community Networks  . . . . . . . . . . . . . . . . . . .  14
     5.2.  Wireless Internet Service Providers (WISPs) . . . . . . .  16
     5.3.  Shared Infrastructure Model . . . . . . . . . . . . . . .  17
     5.4.  Crowdshared Approaches Led by the Users and Third-Party
           Stakeholders  . . . . . . . . . . . . . . . . . . . . . .  19
     5.5.  Rural Utility Cooperatives  . . . . . . . . . . . . . . .  21
     5.6.  Testbeds for Research Purposes  . . . . . . . . . . . . .  22
   6.  Technologies Employed . . . . . . . . . . . . . . . . . . . .  22
     6.1.  Wired . . . . . . . . . . . . . . . . . . . . . . . . . .  22
     6.2.  Wireless  . . . . . . . . . . . . . . . . . . . . . . . .  22
       6.2.1.  Media Access Control (MAC) Protocols for Wireless
               Links . . . . . . . . . . . . . . . . . . . . . . . .  23  802.11 (Wi-Fi)  . . . . . . . . . . . . . . . . .  23  Mobile Technologies . . . . . . . . . . . . . . .  24  Dynamic Spectrum  . . . . . . . . . . . . . . . .  24
   7.  Upper Layers  . . . . . . . . . . . . . . . . . . . . . . . .  26
     7.1.  Layer 3 . . . . . . . . . . . . . . . . . . . . . . . . .  26
       7.1.1.  IP Addressing . . . . . . . . . . . . . . . . . . . .  26
       7.1.2.  Routing Protocols . . . . . . . . . . . . . . . . . .  26  Traditional Routing Protocols . . . . . . . . . .  26  Mesh Routing Protocols  . . . . . . . . . . . . .  27
     7.2.  Transport Layer . . . . . . . . . . . . . . . . . . . . .  27
       7.2.1.  Traffic Management When Sharing Network Resources . .  27
     7.3.  Services Provided . . . . . . . . . . . . . . . . . . . .  28
       7.3.1.  Use of VPNs . . . . . . . . . . . . . . . . . . . . .  29
       7.3.2.  Other Facilities  . . . . . . . . . . . . . . . . . .  29
     7.4.  Security Considerations . . . . . . . . . . . . . . . . .  29
   8.  Informative References  . . . . . . . . . . . . . . . . . . .  30
   Acknowledgements  . . . . . . . . . . . . . . . . . . . . . . . .  40
   Contributors  . . . . . . . . . . . . . . . . . . . . . . . . . .  41
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  42

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1.  Introduction

   One of the aims of the Global Access to the Internet for All (GAIA)
   IRTF Research Group is "to document and share deployment experiences
   and research results to the wider community through scholarly
   publications, white papers, Informational and Experimental RFCs,
   etc."  [GAIA].  In line with this objective, this document proposes a
   classification of "Alternative Network Deployments".  This term
   includes a set of network access models that have emerged in the last
   decade with the aim of providing Internet connections, following
   topological, architectural, governance, and business models that
   differ from the so-called "mainstream" ones, where a company deploys
   the infrastructure connecting the users, who pay a subscription fee
   to be connected and make use of it.

   Several initiatives throughout the world have built these large-scale
   networks, using predominantly wireless technologies (including long
   distance links) due to the reduced cost of using unlicensed spectrum.
   Wired technologies such as fiber are also used in some of these

   The classification considers several types of alternate deployments:
   Community Networks are self-organized networks wholly owned by the
   community; networks acting as Wireless Internet Service Providers
   (WISPs); networks owned by individuals but leased out to network
   operators who use such networks as a low-cost medium to reach the
   underserved population; networks that provide connectivity by sharing
   wireless resources of the users; and finally there are some rural
   utility cooperatives also connecting their members to the Internet.

   The emergence of these networks has been motivated by a variety of
   factors such as the lack of wired and cellular infrastructures in
   rural/remote areas [Pietrosemoli].  In some cases, Alternative
   Networks may provide more localized communication services as well as
   Internet backhaul support through peering agreements with mainstream
   network operators.  In other cases, they are built as a complement or
   an alternative to commercial Internet access provided by mainstream
   network operators.

   The present document is intended to provide a broad overview of
   initiatives, technologies, and approaches employed in these networks,
   including some real examples.  References describing each kind of
   network are also provided.

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1.1.  Mainstream Networks

   In this document, we will use the term "mainstream networks" to
   denote those networks sharing these characteristics:

   o  Regarding scale, they are usually large networks spanning entire

   o  Top-down control of the network and centralized approach.

   o  They require a substantial investment in infrastructure.

   o  Users in mainstream networks do not participate in the network
      design, deployment, operation, governance, and maintenance.

   o  Ownership of the network is never vested in the users themselves.

1.2.  Alternative Networks

   The term "Alternative Network" proposed in this document refers to
   the networks that do not share the characteristics of "mainstream
   network deployments".  Therefore, they may share some of the
   following characteristics:

   o  Relatively small scale (i.e., not spanning entire regions).

   o  Administration may not follow a centralized approach.

   o  They may require a reduced investment in infrastructure, which may
      be shared by the users and commercial and non-commercial entities.

   o  Users in Alternative Networks may participate in the network
      design, deployment, operation, and maintenance.

   o  Ownership of the network is often vested in the users.

2.  Terms Used in This Document

   Considering the role that the Internet currently plays in everyday
   life, this document touches on complex social, political, and
   economic issues.  Some of the concepts and terminology used have been
   the subject of study of various disciplines outside the field of
   networking and are responsible for long debates whose resolution is
   out of the scope of this document.

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   o  "Global north" and "global south".  Although there is no consensus
      on the terms to be used when talking about the different
      development level of countries, we will employ the term "global
      south" to refer to nations with a relatively lower standard of
      living.  This distinction is normally intended to reflect basic
      economic country conditions.  In common practice, Japan in Asia,
      Canada and the United States in northern America, Australia and
      New Zealand in Oceania, and Europe are considered "developed"
      regions or areas [UN], so we will employ the term "global north"
      when talking about them.

   o  The "Digital Divide".  The following dimensions are considered to
      be meaningful when measuring the digital development state of a
      country: infrastructures (availability and affordability), the
      Information and Communications Technology (ICT) sector (human
      capital and technological industry), digital literacy, legal and
      regulatory framework, and content and services.  A lack of digital
      development in one or more of these dimensions is what has been
      referred as the "Digital Divide" [Norris].  It should be noted
      that this "Divide" is not only present between different countries
      but between zones of the same country, despite its degree of

   o  "Urban" and "rural" zones.  There is no single definition of
      "rural" or "urban", as each country and various international
      organizations define these terms differently, mainly based on the
      number of inhabitants, the population density, and the distance
      between houses [UNStats].  For networking purposes, the primary
      distinction is likely the average distance between customers,
      typically measured by population density, as well as the distance
      to the nearest Internet point-of-presence, i.e., the distance to
      be covered by "middle mile" or backhaul connectivity.  Some
      regions with low average population density may cluster almost all
      inhabitants into a small number of relatively dense small towns,
      for example, while residents may be dispersed more evenly in

   o  Demand.  In economics, it describes a consumer's desire and
      willingness to pay a price for a specific good or service.

   o  Provision is the act of making an asset available for sale.  In
      this document, we will mainly use it as the act of making a
      network service available to the inhabitants of a zone.

   o  Underserved area.  Area in which the telecommunication market
      permanently fails to provide the information and communications
      services demanded by the population.

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   o  Free, open, and neutral networks.  Their principles have been
      summarized this way [Baig]:

      *  You have the freedom to use the network for any purpose as long
         as you do not harm the operation of the network itself, the
         rights of other users, or the principles of neutrality that
         allow contents and services to flow without deliberate

      *  You have the right to understand the network, to know its
         components, and to spread knowledge of its mechanisms and

      *  You have the right to offer services and content to the network
         on your own terms.

      *  You have the right to join the network, and the responsibility
         to extend this set of rights to anyone according to these same

3.  Scenarios Where Alternative Networks Are Deployed

   Different studies have reported that as much as 60% of the people on
   the planet do not have Internet connectivity [Sprague]
   [InternetStats].  In addition, those unconnected are unevenly
   distributed: only 31% of the population in "global south" countries
   had access in 2014, against 80% in "global north" countries
   [WorldBank2016].  This is one of the reasons behind the inclusion of
   the objective to "significantly increase access to information and
   communications technology and strive to provide universal and
   affordable access to the Internet in least developed countries by
   2020," as one of the targets in the Sustainable Development Goals
   (SDGs) [SDG], considered as a part of "Goal 9.  Build resilient
   infrastructure, promote inclusive and sustainable industrialization
   and foster innovation."

   For the purpose of this document, a distinction between "global
   north" and "global south" zones is made, highlighting the factors
   related to ICT, which can be quantified in terms of:

   o  The availability of both national and international bandwidth, as
      well as equipment.

   o  The difficulty in paying for the services and the devices required
      to access the ICTs.

   o  The instability and/or lack of power supply.

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   o  The scarcity of qualified staff.

   o  The existence of a policy and regulatory framework that hinders
      the development of these models in favor of state monopolies or

   In this context, the World Summit of the Information Society [WSIS]
   aimed at achieving "a people-centred, inclusive and development-
   oriented Information Society, where everyone can create, access,
   utilize and share information and knowledge.  Therefore, enabling
   individuals, communities and people to achieve their full potential
   in promoting their sustainable development and improving their
   quality of life".  It also called upon "governments, private sector,
   civil society and international organizations" to actively engage to
   work towards the bridging of the digital divide.

   Some Alternative Networks have been deployed in underserved areas,
   where citizens may be compelled to take a more active part in the
   design and implementation of ICT solutions.  However, Alternative
   Networks (e.g., [Baig]) are also present in some "global north"
   countries, being built as an alternative to commercial ones managed
   by mainstream network operators.

   The consolidation of a number of mature Alternative Networks (e.g.,
   Community Networks) sets a precedent for civil society members to
   become more active in the search for alternatives to provide
   themselves with affordable access.  Furthermore, Alternative Networks
   could contribute to bridge the digital divide by increasing human
   capital and promoting the creation of localized content and services.

3.1.  Urban vs. Rural Areas

   The differences presented in the previous section are not only
   present between countries, but within them too.  This is especially
   the case for rural inhabitants, who represent approximately 55% of
   the world's population [IFAD2011], with 78% of them in "global south"
   countries [ITU2011].  According to the World Bank, adoption gaps
   "between rural and urban populations are falling for mobile phones
   but increasing for the internet" [WorldBank2016].

   Although it is impossible to generalize among them, there exist some
   common features in rural areas that have prevented incumbent
   operators from providing access and that, at the same time, challenge
   the deployment of alternative infrastructures [Brewer] [Nungu]
   [Simo_c].  For example, a high network latency was reported in
   [Johnson_b], which could be in the order of seconds during some

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   These challenges include:

   o  Low per capita income, as the local economy is mainly based on
      subsistence agriculture, farming, and fishing.

   o  Scarcity or absence of basic infrastructures, such as electricity,
      water, and access roads.

   o  Low population density and distance (spatial or effective) between
      population clusters.

   o  Underdeveloped social services, such as healthcare and education.

   o  Lack of adequately educated and trained technicians, and high
      potential for those (few) trained to leave the community
      incentivized by better opportunities, higher salaries, or the
      possibility of starting their own companies [McMahon].

   o  High cost of Internet access [Mathee].

   o  Harsh environments leading to failure in electronic communication
      devices [Johnson_a], which reduces the reliability of the network.

   Some of these factors challenge the stability of Alternative Networks
   and the services they provide: scarcity of spectrum, scale, and
   heterogeneity of devices.  However, the proliferation of Alternative
   Networks [Baig] together with the raising of low-cost, low-
   consumption, low-complexity off-the-shelf wireless devices have
   allowed and simplified the deployment and maintenance of alternative
   infrastructures in rural areas.

3.2.  Topology Patterns Followed by Alternative Networks

   Alternative Networks, considered self-managed and self-sustained,
   follow different topology patterns [Vega_a].  Generally, these
   networks grow spontaneously and organically, that is, the network
   grows without specific planning and deployment strategy and the
   routing core of the network tends to fit a power law distribution.
   Moreover, these networks are composed of a high number of
   heterogeneous devices with the common objective of freely connecting
   and increasing the network coverage and the reliability.  Although
   these characteristics increase the entropy (e.g., by increasing the
   number of routing protocols), they have resulted in an inexpensive
   solution to effectively increase the network size.  One such example
   is [Vega_a], which has had an exponential growth rate in
   the number of operating nodes during the last decade.

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   Regularly, rural areas in these networks are connected through long-
   distance links and/or wireless mesh networks, which in turn convey
   the Internet connection to relevant organizations or institutions.
   In contrast, in urban areas, users tend to share and require mobile
   access.  Since these areas are also likely to be covered by
   commercial ISPs, the provision of wireless access by virtual
   operators like [Fon] may constitute a way to extend the user capacity
   to the network.  Other proposals like "Virtual Public Networks"
   [Sathiaseelan_a] can also extend the service.

4.  Classification Criteria

   The classification of Alternative Network Deployments, presented in
   this document, is based on the following criteria:

4.1.  Entity behind the Network

   The entity (or entities) or individuals behind an Alternative Network
   can be:

   o  A community of users.

   o  A public stakeholder.

   o  A private company.

   o  Supporters of a crowdshared approach.

   o  A community that already owns the infrastructure and shares it
      with an operator, who, in turn, may also use it for backhauling

   o  A research or academic entity.

   The above actors may play different roles in the design, financing,
   deployment, governance, and promotion of an Alternative Network.  For
   example, each of the members of a Community Network maintains the
   ownership over the equipment they have contributed, whereas in others
   there is a single entity, e.g., a private company who owns the
   equipment, or at least a part of it.

4.2.  Purpose

   Alternative Networks can be classified according to their purpose and
   the benefits they bring compared to mainstream solutions, regarding
   economic, technological, social, or political objectives.  These
   benefits could be enjoyed mostly by the actors involved (e.g.,
   lowering costs or gaining technical expertise) or by the local

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   community (e.g., Internet access in underserved areas) or by the
   society as a whole (e.g., network neutrality).

   The benefits provided by Alternative Networks include, but are not
   limited to:

   o  Extending coverage to underserved areas (users and communities).

   o  Providing affordable Internet access for all.

   o  Reducing initial capital expenditures (for the network and the end
      user, or both).

   o  Providing additional sources of capital (beyond the traditional
      carrier-based financing).

   o  Reducing ongoing operational costs (such as backhaul or network

   o  Leveraging expertise and having a place for experimentation and

   o  Reducing hurdles to adoption (e.g., digital literacy, literacy in
      general, and relevance).

   o  Providing an alternative service in case of natural disasters and
      other extreme situations.

   o  Community building, social cohesion, and quality of life

   o  Experimentation with alternative governance and ownership models
      for treating network infrastructures as a commons.

   o  Raising awareness of political debates around issues like network
      neutrality, knowledge sharing, access to resources, and more.

   Note that the different purposes of Alternative Networks can be more
   or less explicitly stated and they could also evolve over time based
   on the internal dynamics and external events.  For example, the Red
   Hook WIFI network in Brooklyn [Redhook] started as a Community
   Network focusing more on local applications and community building
   [TidePools], but it became widely known when it played a key role as
   an alternative service available during the Sandy storm [Tech]

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   Moreover, especially for those networks with more open and horizontal
   governance models, the underlying motivations of those involved may
   be very diverse, ranging from altruistic ones related to the desire
   of free sharing of Internet connectivity and various forms of
   activism to personal benefits from the experience and expertise
   through the active participation in the deployment and management of
   a real and operational network.

4.3.  Governance and Sustainability Model

   Different governance models are present in Alternative Networks.
   They may range from some open and horizontal models, with an active
   participation of the users (e.g., Community Networks) to a more
   centralized model, where a single authority (e.g., a company or a
   public stakeholder) plans and manages the network, even if it is
   (total or partially) owned by a community.

   Regarding sustainability, some networks grow "organically" as a
   result of the new users who join and extend the network, contributing
   their own hardware.  In some other cases, the existence of previous
   infrastructure (owned by the community or the users) may lower the
   capital expenditures of an operator, who can therefore provide the
   service with better economic conditions.

4.4.  Technologies Employed

   o  Standard Wi-Fi.  Many Alternative Networks are based on the
      standard IEEE 802.11 [IEEE.802.11] using the Distributed
      Coordination Function.

   o  Wi-Fi-based Long Distance (WiLD) networks.  These can work with
      either Carrier Sense Multiple Access with Collision Avoidance
      (CSMA/CA) or an alternative Time Division Multiple Access (TDMA)
      Media Access Control (MAC) [Simo_b].

   o  TDMA.  It can be combined with a Wi-Fi protocol, in a non-standard
      way [airMAX].  This configuration allows each client to send and
      receive data using pre-designated timeslots.

   o  802.16-compliant (Worldwide Interoperability for Microwave Access
      (WiMax)) [IEEE.802.16] systems over non-licensed bands.

   o  Dynamic Spectrum Solutions (e.g., based on the use of TV White
      Spaces).  A set of television frequencies that can be utilized by
      secondary users in locations where they are unused, e.g., IEEE
      802.11af [IEEE.802.11AF] or 802.22 [IEEE.802.22].

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   o  Satellite solutions can also be employed to give coverage to wide
      areas, as proposed in the RIFE project (

   o  Low-cost optical fiber systems are also used to connect households
      in different places.

4.5.  Typical Scenarios

   The scenarios where Alternative Networks are usually deployed can be
   classified as:

   o  Urban/rural areas.

   o  "Global north" / "global south" countries.

5.  Classification of Alternative Networks

   This section classifies Alternative Networks according to the
   criteria explained previously.  Each of them has different incentive
   structures, maybe common technological challenges, but most
   importantly interesting usage challenges that feed into the
   incentives as well as the technological challenges.

   At the beginning of each subsection, a table is presented including a
   classification of each network according to the criteria listed in
   the "Classification Criteria" subsection.  Real examples of each kind
   of Alternative Network are cited.

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5.1.  Community Networks

   | Entity behind  | community                                        |
   | the network    |                                                  |
   | Purpose        | all the goals listed in Section 4.2 may be       |
   |                | present                                          |
   | Governance and | participatory administration model: non-         |
   | sustainability | centralized and open building and maintenance;   |
   | model          | users may contribute their own hardware          |
   | Technologies   | Wi-Fi [IEEE.802.11] (standard and non-standard   |
   | employed       | versions) and optical fiber                      |
   | Typical        | urban and rural                                  |
   | scenarios      |                                                  |

          Table 1: Characteristics Summary for Community Networks

   Community Networks are non-centralized, self-managed networks sharing
   these characteristics:

   o  They start and grow organically, and they are open to
      participation from everyone, sharing an open participation
      agreement.  Community members directly contribute active (not just
      passive) network infrastructure.  The network grows as new hosts
      and links are added.

   o  Knowledge about building and maintaining the network and ownership
      of the network itself is non-centralized and open.  Different
      degrees of centralization can be found in Community Networks.  In
      some of them, a shared platform (e.g., a website) may exist where
      minimum coordination is performed.  Community members with the
      right permissions have an obvious and direct form of
      organizational control over the overall organization of the
      network (e.g., IP addresses, routing, etc.) in their community
      (not just their own participation in the network).

   o  The network can serve as a backhaul for providing a whole range of
      services and applications, from completely free to even commercial

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   Hardware and software used in Community Networks can be very diverse
   and customized, even inside one network.  A Community Network can
   have both wired and wireless links.  Multiple routing protocols or
   network topology management systems may coexist in the network.

   These networks grow organically, since they are formed by the
   aggregation of nodes belonging to different users.  A minimal
   governance infrastructure is required in order to coordinate IP
   addressing, routing, etc.  Several examples of Community Networks are
   described in [Braem].  A technological analysis of a Community
   Network is presented in [Vega_b], which focuses on technological
   network diversity, topology characteristics, the evolution of the
   network over time, robustness and reliability, and networking service

   These networks follow a participatory administration model, which has
   been shown to be effective in connecting geographically dispersed
   people, thus enhancing and extending digital Internet rights.

   Users adding new infrastructure (i.e., extensibility) can be used to
   formulate another definition: A Community Network is a network in
   which any participant in the system may add link segments to the
   network in such a way that the new segments can support multiple
   nodes and adopt the same overall characteristics as those of the
   joined network, including the capacity to further extend the network.
   Once these link segments are joined to the network, there is no
   longer a meaningful distinction between the previous and the new
   extent of the network.  The term "participant" refers to an
   individual, who may become the user, provider, and manager of the
   network at the same time.

   In Community Networks, profit can only be made by offering services
   and not simply by supplying the infrastructure, because the
   infrastructure is neutral, free, and open (mainstream Internet
   Service Providers base their business on the control of the
   infrastructure).  In Community Networks, everybody usually keeps the
   ownership of what he/she has contributed or leaves the stewardship of
   the equipment to the network as a whole (the commons), even loosing
   track of the ownership of a particular equipment itself, in favor of
   the community.

   The majority of Community Networks comply with the definition of Free
   Network, included in Section 2.

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5.2.  Wireless Internet Service Providers (WISPs)

   | Entity behind  | company                                          |
   | the network    |                                                  |
   | Purpose        | to serve underserved areas; to reduce capital    |
   |                | expenditures in Internet access; and to provide  |
   |                | additional sources of capital                    |
   | Governance and | operated by a company that provides the          |
   | sustainability | equipment; centralized administration            |
   | model          |                                                  |
   | Technologies   | wireless, e.g., [IEEE.802.11] and [IEEE.802.16]  |
   | employed       | and unlicensed frequencies                       |
   | Typical        | rural (urban deployments also exist)             |
   | scenarios      |                                                  |

                Table 2: Characteristics Summary for WISPs

   WISPs are commercially operated wireless Internet networks that
   provide Internet and/or Voice over Internet (VoIP) services.  They
   are most common in areas not covered by mainstream telecommunications
   companies or ISPs.  WISPs mostly use wireless point-to-multipoint
   links using unlicensed spectrum but often must resort to licensed
   frequencies.  Use of licensed frequencies is common in regions where
   unlicensed spectrum is either perceived to be crowded or too
   unreliable to offer commercial services, or where unlicensed spectrum
   faces regulatory barriers impeding its use.

   Most WISPs are operated by local companies responding to a perceived
   market gap.  There is a small but growing number of WISPs, such as
   [Airjaldi] in India, that have expanded from local service into
   multiple locations.

   Since 2006, the deployment of cloud-managed WISPs has been possible
   with hardware from companies such as [Meraki] and later [OpenMesh]
   and others.  Until recently, however, most of these services have
   been aimed at "global north" markets.  In 2014, a cloud-managed WISP
   service aimed at "global south" markets was launched [Everylayer].

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5.3.  Shared Infrastructure Model

   | Entity behind  | shared: companies and users                      |
   | the network    |                                                  |
   | Purpose        | to eliminate a capital expenditures barrier (to  |
   |                | operators); lower the operating expenses         |
   |                | (supported by the community); and extend         |
   |                | coverage to underserved areas                    |
   | Governance and | the community rents the existing infrastructure  |
   | sustainability | to an operator                                   |
   | model          |                                                  |
   | Technologies   | wireless in non-licensed bands, mobile           |
   | employed       | femtocells, WiLD networks [WiLD], and/or low-    |
   |                | cost fiber                                       |
   | Typical        | rural areas, and more particularly rural areas   |
   | scenarios      | in "global south" regions                        |

        Table 3: Characteristics Summary for Shared Infrastructure

   In mainstream networks, the operator usually owns the
   telecommunications infrastructure required for the service or
   sometimes rents infrastructure to/from other companies.  The problem
   arises in large areas with low population density, in which neither
   the operator nor the other companies have deployed infrastructure and
   such deployments are not likely to happen due to the low potential
   return on investment.

   When users already own deployed infrastructure, either individually
   or as a community, sharing that infrastructure with an operator can
   benefit both parties and is a solution that has been deployed in some
   areas.  For the operator, this provides a significant reduction in
   the initial investment needed to provide services in small rural
   localities because capital expenditure is only associated with the
   access network.  Renting capacity in the users' network for
   backhauling only requires an increment in the operating expenditure.
   This approach also benefits the users in two ways: they obtain
   improved access to telecommunications services that would not be
   accessible otherwise, and they can derive some income from the
   operator that helps to offset the network's operating costs,
   particularly for network maintenance.

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   One clear example of the potential of the "shared infrastructure
   model" nowadays is the deployment of 3G services in rural areas in
   which there is a broadband rural Community Network.  Since the
   inception of femtocells (small, low-power cellular base stations),
   there are complete technical solutions for low-cost 3G coverage using
   the Internet as a backhaul.  If a user or community of users has an
   IP network connected to the Internet with some excess capacity,
   placing a femtocell in the user premises benefits both the user and
   the operator, as the user obtains better coverage and the operator
   does not have to support the cost of the backhaul infrastructure.
   Although this paradigm was conceived for improved indoor coverage,
   the solution is feasible for 3G coverage in underserved rural areas
   with low population density (i.e., villages), where the number of
   simultaneous users and the servicing area are small enough to use
   low-cost femtocells.  Also, the amount of traffic produced by these
   cells can be easily transported by most community broadband rural

   Some real examples can be referenced in the TUCAN3G project, which
   deployed demonstrator networks in two regions in the Amazon forest in
   Peru [Simo_d].  In these networks [Simo_a], the operator and several
   rural communities cooperated to provide services through rural
   networks built up with WiLD links [WiLD].  In these cases, the
   networks belonged to the public health authorities and were deployed
   with funds that came from international cooperation for telemedicine
   purposes.  Publications that justify the feasibility of this approach
   can also be found on that website.

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5.4.  Crowdshared Approaches Led by the Users and Third-Party

   | Entity behind  | community, public stakeholders, private          |
   | the network    | companies, and supporters of a crowdshared       |
   |                | approach                                         |
   | Purpose        | sharing connectivity and resources               |
   | Governance and | users share their capacity, coordinated by a     |
   | sustainability | Virtual Network Operator (VNO); different models |
   | model          | may exist, depending on the nature of the VNO    |
   | Technologies   | Wi-Fi [IEEE.802.11]                              |
   | employed       |                                                  |
   | Typical        | urban and rural                                  |
   | scenarios      |                                                  |

        Table 4: Characteristics Summary for Crowdshared Approaches

   These networks can be defined as a set of nodes whose owners share
   common interests (e.g., sharing connectivity; resources; and
   peripherals) regardless of their physical location.  They conform to
   the following approach: the home router creates two wireless networks
   -- one of them is normally used by the owner, and the other one is
   public.  A small fraction of the bandwidth is allocated to the public
   network to be employed by any user of the service in the immediate
   area.  Some examples are described in [PAWS] and [Sathiaseelan_c].
   Other examples are found in the networks created and managed by city
   councils (e.g., [Heer]).  The "openwireless movement"
   ( also promotes the sharing of private
   wireless networks.

   Some companies [Fon] also promote the use of Wi-Fi routers with dual
   access: a Wi-Fi network for the user and a shared one.  Adequate
   Authentication, Authorization, and Accounting (AAA) policies are
   implemented, so people can join the network in different ways: they
   can buy a router, so they can share their connection and in turn,
   they get access to all the routers associated with the community.
   Some users can even get some revenue every time another user connects
   to their Wi-Fi Access Point.  Users that are not part of the
   community can buy passes in order to use the network.  Some
   mainstream telecommunications operators collaborate with these

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   communities by including the functionality required to create the two
   access networks in their routers.  Some of these efforts are surveyed
   in [Shi].

   The elements involved in a crowdshared network are summarized below:

   o  Interest: A parameter capable of providing a measure (cost) of the
      attractiveness of a node in a specific location, at a specific
      instance in time.

   o  Resources: A physical or virtual element of a global system.  For
      instance, bandwidth; energy; data; and devices.

   o  The owner: End users who sign up for the service and share their
      network capacity.  As a counterpart, they can access another
      owner's home network capacity for free.  The owner can be an end
      user or an entity (e.g., operator; virtual mobile network
      operator; or municipality) that is to be made responsible for any
      actions concerning his/her device.

   o  The user: A legal entity or an individual using or requesting a
      publicly available electronic communications service for private
      or business purposes, without necessarily having subscribed to
      such service.

   o  The VNO: An entity that acts in some aspects as a network
      coordinator.  It may provide services such as initial
      authentication or registration and, eventually, trust relationship
      storage.  A VNO is not an ISP given that it does not provide
      Internet access (e.g., infrastructure or naming).  A VNO is not an
      Application Service Provider (ASP) either since it does not
      provide user services.  VNOs may also be stakeholders with socio-
      environmental objectives.  They can be local governments,
      grassroots user communities, charities, or even content operators,
      smart grid operators, etc.  They are the ones who actually run the

   o  Network operators: They have a financial incentive to lease out
      unused capacity [Sathiaseelan_b] at a lower cost to the VNOs.

   VNOs pay the sharers and the network operators, thus creating an
   incentive structure for all the actors: the end users get money for
   sharing their network, and the network operators are paid by the
   VNOs, who in turn accomplish their socio-environmental role.

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5.5.  Rural Utility Cooperatives

   | Entity behind the   | rural utility cooperative                   |
   | network             |                                             |
   | Purpose             | to serve underserved areas and to reduce    |
   |                     | capital expenditures in Internet access     |
   | Governance and      | the cooperative partners with an ISP who    |
   | sustainability      | manages the network                         |
   | model               |                                             |
   | Technologies        | wired (fiber) and wireless                  |
   | employed            |                                             |
   | Typical scenarios   | rural                                       |

      Table 5: Characteristics Summary for Rural Utility Cooperatives

   A utility cooperative is a type of cooperative that delivers a public
   utility to its members.  For example, in the United States, rural
   electric cooperatives have provided electric service starting in the
   1930s, especially in areas where investor-owned utility would not
   provide service, believing there would be insufficient revenue to
   justify the capital expenditures required.  Similarly, in many
   regions with low population density, traditional Internet Service
   Providers such as telephone companies or cable TV companies are
   either not providing service at all or only offering low-speed DSL
   service.  Some rural electric cooperatives started installing fiber
   optic lines to run their smart grid applications, but they found they
   could provide fiber-based broadband to their members at little
   additional cost [Cash].  In some of these cases, rural electric
   cooperatives have partnered with local ISPs to provide Internet
   connection to their members [Carlson].  More information about these
   utilities and their management can be found in [NewMexico] and

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5.6.  Testbeds for Research Purposes

   | Entity behind    | research/academic entity                       |
   | the network      |                                                |
   | Purpose          | research                                       |
   | Governance and   | the management is initially coordinated by the |
   | sustainability   | research entity, but it may end up in a        |
   | model            | different model                                |
   | Technologies     | wired and wireless                             |
   | employed         |                                                |
   | Typical          | urban and rural                                |
   | scenarios        |                                                |

               Table 6: Characteristics Summary for Testbeds

   In some cases, the initiative to start the network is not from the
   community but from a research entity (e.g., a university), with the
   aim of using it for research purposes [Samanta] [Bernardi].

   The administration of these networks may start being centralized in
   most cases (administered by the academic entity) and may end up in a
   non-centralized model in which other local stakeholders assume part
   of the network administration (for example, see [Rey]).

6.  Technologies Employed

6.1.  Wired

   In many ("global north" or "global south") countries, it may happen
   that national service providers decline to provide connectivity to
   tiny and isolated villages.  So in some cases, the villagers have
   created their own optical fiber networks.  This is the case in
   Lowenstedt, Germany [Lowenstedt] or in some parts of

6.2.  Wireless

   The vast majority of Alternative Network Deployments are based on
   different wireless technologies [WNDW].  Below we summarize the
   options and trends when using these features in Alternative Networks.

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6.2.1.  Media Access Control (MAC) Protocols for Wireless Links

   Different protocols for MAC, which also include physical layer (PHY)
   recommendations, are widely used in Alternative Network Deployments.
   Wireless standards ensure interoperability and usability to those who
   design, deploy, and manage wireless networks.  In addition, they then
   ensure the low cost of equipment due to economies of scale and mass

   The standards used in the vast majority of Alternative Networks come
   from the IEEE Standard Association's IEEE 802 Working Group.
   Standards developed by other international entities can also be used,
   such as, e.g., the European Telecommunications Standards Institute
   (ETSI).  802.11 (Wi-Fi)

   The standard we are most interested in is 802.11 a/b/g/n/ac, as it
   defines the protocol for Wireless LAN.  It is also known as "Wi-Fi".
   The original release (a/b) was issued in 1999 and allowed for rates
   up to 54 Mbit/s.  The latest release (802.11ac) approved in 2013
   reaches up to 866.7 Mbit/s.  In 2012, the IEEE issued an 802.11
   standard that consolidated all the previous amendments [IEEE.802.11].
   The document is freely downloadable from the IEEE Standards
   Association [IEEE].

   The MAC protocol in 802.11 is called CSMA/CA and was designed for
   short distances; the transmitter expects the reception of an
   acknowledgment for each transmitted unicast packet and if a certain
   waiting time is exceeded, the packet is retransmitted.  This behavior
   makes necessary the adaptation of several MAC parameters when 802.11
   is used in long links [Simo_b].  Even with this adaptation, distance
   has a significant negative impact on performance.  For this reason,
   many vendors implement alternative medium access techniques that are
   offered alongside the standard CSMA/CA in their outdoor 802.11
   products.  These alternative proprietary MAC protocols usually employ
   some type of TDMA.  Low-cost equipment using these techniques can
   offer high throughput at distances above 100 kilometers.

   Different specifications of 802.11 operate in different frequency
   bands. 802.11b/g/n operates in 2.4 GHz, but 802.11a/n/ac operates in
   5 GHz.  This fact is used in some Community Networks in order to
   separate ordinary and "backbone" nodes:

   o  Typical routers running mesh firmware in homes, offices, and
      public spaces operate at 2.4 GHz.

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   o  Special routers running mesh firmware as well but broadcasting and
      receiving on the 5 GHz band are used in point-to-point connections
      only.  They are helpful to create a "backbone" on the network that
      can both connect neighborhoods to one another when reasonable
      connections with 2.4 GHz nodes are not possible, and they ensure
      that users of 2.4 GHz nodes are within a few hops to strong and
      stable connections to the rest of the network.  Mobile Technologies

   Global System for Mobile Communications (GSM), from ETSI, has also
   been used in Alternative Networks as a Layer 2 option, as explained
   in [Mexican], [Village], and [Heimerl].  Open source GSM code
   projects such as OpenBTS ( or OpenBSC
   ( have created an ecosystem with the
   participation of several companies such as, e.g., [Rangenetworks],
   [Endaga], and [YateBTS].  This enables deployments of voice, SMS, and
   Internet services over Alternative Networks with an IP-based

   Internet navigation is usually restricted to relatively low bit rates
   (see, e.g., [Osmocom]).  However, leveraging on the evolution of
   Third Generation Partnership Project (3GPP) standards, a trend can be
   observed towards the integration of 4G [Spectrum] [YateBTS] or 5G
   [Openair] functionalities, with significant increase of achievable
   bit rates.

   Depending on factors such as the allocated frequency band, the
   adoption of licensed spectrum can have advantages over the eventually
   higher frequencies used for Wi-Fi, in terms of signal propagation
   and, consequently, coverage.  Other factors favorable to 3GPP
   technologies, especially GSM, are the low cost and energy consumption
   of handsets, which facilitate its use by low-income communities.  Dynamic Spectrum

   Some Alternative Networks make use of TV White Spaces [Lysko] -- a
   set of UHF and VHF television frequencies that can be utilized by
   secondary users in locations where they are unused by licensed
   primary users such as television broadcasters.  Equipment that makes
   use of TV White Spaces is required to detect the presence of existing
   unused TV channels by means of a spectrum database and/or spectrum
   sensing in order to ensure that no harmful interference is caused to
   primary users.  In order to smartly allocate interference-free
   channels to the devices, cognitive radios are used that are able to
   modify their frequency, power, and modulation techniques to meet the
   strict operating conditions required for secondary users.

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   The use of the term "White Spaces" is often used to describe "TV
   White Spaces" as the VHF and UHF television frequencies were the
   first to be exploited on a secondary use basis.  There are two
   dominant standards for TV White Space communication: (i) the 802.11af
   standard [IEEE.802.11AF] -- an adaptation of the 802.11 standard for
   TV White Space bands -- and (ii) the IEEE 802.22 standard
   [IEEE.802.22] for long-range rural communication.  802.11af

   802.11af [IEEE.802.11AF] is a modified version of the 802.11 standard
   operating in TV White Space bands using cognitive radios to avoid
   interference with primary users.  The standard is often referred to
   as "White-Fi" or "Super Wi-Fi" and was approved in February 2014.
   802.11af contains much of the advances of all the 802.11 standards
   including recent advances in 802.11ac such as up to four bonded
   channels, four spatial streams, and very high-rate 256 QAM
   (Quadrature Amplitude Modulation) but with improved in-building
   penetration and outdoor coverage.  The maximum data rate achievable
   is 426.7 Mbit/s for countries with 6/7 MHz channels and 568.9 Mbit/s
   for countries with 8 MHz channels.  Coverage is typically limited to
   1 km although longer range at lower throughput and using high gain
   antennas will be possible.

   Devices are designated as enabling stations (Access Points) or
   dependent stations (clients).  Enabling stations are authorized to
   control the operation of a dependent station and securely access a
   geolocation database.  Once the enabling station has received a list
   of available White Space channels, it can announce a chosen channel
   to the dependent stations for them to communicate with the enabling
   station. 802.11af also makes use of a registered location server -- a
   local database that organizes the geographic location and operating
   parameters of all enabling stations.  802.22

   802.22 [IEEE.802.22] is a standard developed specifically for long-
   range rural communications in TV White Space frequencies and was
   first approved in July 2011.  The standard is similar to the 802.16
   (WiMax) [IEEE.802.16] standard with an added cognitive radio ability.
   The maximum throughput of 802.22 is 22.6 Mbit/s for a single 8 MHz
   channel using 64-QAM modulation.  The achievable range using the
   default MAC scheme is 30 km; however, 100 km is possible with special
   scheduling techniques.  The MAC of 802.22 is specifically customized
   for long distances -- for example, slots in a frame destined for more
   distant Consumer Premises Equipment (CPE) are sent before slots
   destined for nearby CPEs.

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   Base stations are required to have a Global Positioning System (GPS)
   and a connection to the Internet in order to query a geolocation
   spectrum database.  Once the base station receives the allowed TV
   channels, it communicates a preferred operating TV White Space
   channel with the CPE devices.  The standard also includes a
   coexistence mechanism that uses beacons to make other 802.22 base
   stations aware of the presence of a base station that is not part of
   the same network.

7.  Upper Layers

7.1.  Layer 3

7.1.1.  IP Addressing

   Most Community Networks use private IPv4 address ranges, as defined
   by [RFC1918].  The motivation for this was the lower cost and the
   simplified IP allocation because of the large available address

   Most known Alternative Networks started in or around the year 2000.
   IPv6 was fully specified by then, but almost all Alternative Networks
   still use IPv4.  A survey [Avonts] indicated that IPv6 rollout
   presented a challenge to Community Networks.  However, some of them
   have already adopted it, such as

7.1.2.  Routing Protocols

   As stated in previous sections, Alternative Networks are composed of
   possibly different Layer 2 devices, resulting in a mesh of nodes.  A
   connection between different nodes is not guaranteed, and the link
   stability can vary strongly over time.  To tackle this, some
   Alternative Networks use mesh routing protocols for Mobile Ad Hoc
   Networks (MANETs), while other ones use more traditional routing
   protocols.  Some networks operate multiple routing protocols in
   parallel.  For example, they may use a mesh protocol inside different
   islands and rely on traditional routing protocols to connect these
   islands.  Traditional Routing Protocols

   The Border Gateway Protocol (BGP), as defined by [RFC4271], is used
   by a number of Community Networks because of its well-studied
   behavior and scalability.

   For similar reasons, smaller networks opt to run the Open Shortest
   Path First (OSPF) protocol, as defined by [RFC2328].

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   A large number of Alternative Networks use customized versions of the
   Optimized Link State Routing (OLSR) Protocol [RFC3626].  The open
   source project [OLSR] has extended the protocol with the Expected
   Transmission Count (ETX) metric [Couto] and other features for its
   use in Alternative Networks, especially wireless ones.  A new version
   of the protocol, named OLSRv2 [RFC7181], is becoming used in some
   Community Networks [Barz].

   Better Approach To Mobile Ad Hoc Networking (B.A.T.M.A.N.) Advanced
   [Seither] is a Layer 2 routing protocol, which creates a bridged
   network and allows seamless roaming of clients between wireless

   Some networks also run the BatMan-eXperimental Version 6 (BMX6)
   protocol [Neumann_a], which is based on IPv6 and tries to exploit the
   social structure of Alternative Networks.

   Babel [RFC6126] is a Layer 3 loop-avoiding distance-vector routing
   protocol that is robust and efficient both in wired and wireless mesh

   In [Neumann_b], a study of three proactive mesh routing protocols
   (BMX6, OLSR, and Babel) is presented, in terms of scalability,
   performance, and stability.

7.2.  Transport Layer

7.2.1.  Traffic Management When Sharing Network Resources

   When network resources are shared (as, e.g., in the networks
   explained in Section 5.4), special care has to be taken with the
   management of the traffic at upper layers.  From a crowdshared
   perspective, and considering just regular TCP connections during the
   critical sharing time, the Access Point offering the service is
   likely to be the bottleneck of the connection.

   This is the main concern of sharers, having several implications.  In
   some cases, an adequate Active Queue Management (AQM) mechanism that
   implements a Less-than-Best-Effort (LBE) [RFC6297] policy for the
   user is used to protect the sharer.  Achieving LBE behavior requires
   the appropriate tuning of well-known mechanisms such as Explicit
   Congestion Notification (ECN) [RFC3168], Random Early Detection (RED)
   [RFC7567], or other more recent AQM mechanisms that aid low latency
   such as Controlled Delay (CoDel) [CoDel] and Proportional Integral
   controller Enhanced (PIE) [PIE] design.

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7.3.  Services Provided

   This section provides an overview of the services provided by the
   network.  Many Alternative Networks can be considered Autonomous
   Systems, being (or aspiring to be) a part of the Internet.

   The services provided can include, but are not limited to:

   o  Web browsing.

   o  Email.

   o  Remote desktop (e.g., using my home computer and my Internet
      connection when I am away).

   o  FTP file sharing (e.g., distribution of software and media).

   o  VoIP (e.g., with SIP).

   o  Peer-to-Peer (P2P) file sharing.

   o  Public video cameras.

   o  DNS.

   o  Online game servers.

   o  Jabber instant messaging.

   o  Weather stations.

   o  Network monitoring.

   o  Videoconferencing/streaming.

   o  Radio streaming.

   o  Message/bulletin board.

   o  Local cloud storage services.

   Due to bandwidth limitations, some services (file sharing, VoIP,
   etc.) may not be allowed in some Alternative Networks.  In some of
   these cases, a number of federated proxies provide web-browsing
   service for the users.

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   Some specialized services have been specifically developed for
   Alternative Networks:

   o  Inter-network peering/VPNs

   o  Community-oriented portals (e.g.,

   o  Network monitoring/deployment/maintenance platforms.

   o  VoIP sharing between networks, allowing cheap calls between

   o  Sensor networks and citizen science built by adding sensors to

   o  Community radio/TV stations.

   Other services (e.g., local wikis as used in community portals; see can also provide useful information when
   supplied through an Alternative Network, although they were not
   specifically created for them.

7.3.1.  Use of VPNs

   Some "micro-ISPs" may use the network as a backhaul for providing
   Internet access, setting up VPNs from the client to a machine with
   Internet access.

   Many Community Networks also use VPNs to connect multiple disjoint
   parts of their networks together.  In some others, every node
   establishes a VPN tunnel as well.

7.3.2.  Other Facilities

   Other facilities, such as NTP or Internet Relay Chat (IRC) servers
   may also be present in Alternative Networks.

7.4.  Security Considerations

   No security issues have been identified for this document.

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8.  Informative References

   [Airjaldi] AirJaldi Networks, "Airjaldi Service", 2015,

   [airMAX]   Ubiquiti Networks, Inc., "airMAX", 2016,

   [Avonts]   Avonts, J., Braem, B., and C. Blondia, "A Questionnaire
              based Examination of Community Networks", IEEE 9th
              International Conference on Wireless and Mobile Computing,
              Networking and Communications (WiMob), pp. 8-15,
              DOI 10.1109/WiMOB.2013.6673333, October 2013.

   [Baig]     Baig, R., Roca, R., Freitag, F., and L. Navarro,
              ", a crowdsourced network infrastructure held in
              common", Computer Networks, Vol. 90, Issue C, pp. 150-165,
              DOI 10.1016/j.comnet.2015.07.009, October 2015.

   [Barz]     Barz, C., Fuchs, C., Kirchhoff, J., Niewiejska, J., and H.
              Rogge, "OLSRv2 for Community Networks", Computer Networks,
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              Mesh Network Testbed in Rural Scotland", Proceedings of
              the 2008 ACM workshop on Wireless networks and systems for
              developing regions, pp. 9-16, DOI 10.1145/1410064.1410067,

   [Braem]    Braem, B., Baig Vinas, R., Kaplan, A., Neumann, A., Vilata
              i Balaguer, I., Tatum, B., Matson, M., Blondia, C., Barz,
              C., Rogge, H., Freitag, F., Navarro, L., Bonicioli, J.,
              Papathanasiou, S., and P. Escrich, "A Case for Research
              with and on Community Networks", ACM SIGCOMM Computer
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              Nedevschi, S., Pal, J., Patra, R., Surana, S., and K.
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              IEEE Computer Society, Vol. 38, Issue 6, pp. 25-38,
              DOI 10.1109/MC.2005.204, 2005.

Saldana, et al.               Informational                    [Page 30]
RFC 7962             Alternative Network Deployments         August 2016

   [Carlson]  Carlson, S. and C. Mitchell, "RS Fiber: Fertile Fields for
              New Rural Internet Cooperative", Institute for Local Self-
              Reliance and Next Century Cities, April 2016,

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              National Rural Electric Cooperative Association (NRECA),
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              Cerda-Alabern, L., "On the topology characterization of
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              high-throughput path metric for multi-hop wireless
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              the Internet for All Research Group (GAIA)", 2016,

Saldana, et al.               Informational                    [Page 31]
RFC 7962             Alternative Network Deployments         August 2016

   [Heer]     Heer, T., Hummen, R., Viol, N., Wirtz, H., Gotz, S., and
              K. Wehrle, "Collaborative municipal Wi-Fi networks-
              challenges and opportunities", 8th IEEE International
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              "IEEE Standards Association",

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              Telecommunications and information exchange between
              systems Local and metropolitan area networks--Specific
              requirements Part 11: Wireless LAN Medium Access Control
              (MAC) and Physical Layer (PHY) Specifications",
              IEEE 802.11-2012, DOI 10.1109/ieeestd.2012.6178212, April
              2012, <

              IEEE, "IEEE Standard for Information technology -
              Telecommunications and information exchange between
              systems - Local and metropolitan area networks - Specific
              requirements - Part 11: Wireless LAN Medium Access Control
              (MAC) and Physical Layer (PHY) specifications - Amendment
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              802.11af-2013, DOI 10.1109/ieeestd.2014.6744566, February
              2014, <

              IEEE, "IEEE Standard for Information technology -
              Telecommunications and information exchange between
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              Wireless Access Systems", IEEE 802.16-2012,
              DOI 10.1109/ieeestd.2012.6272299, August 2012,

Saldana, et al.               Informational                    [Page 32]
RFC 7962             Alternative Network Deployments         August 2016

              IEEE, "IEEE Standard for Information technology-- Local
              and metropolitan area networks-- Specific requirements--
              Part 22: Cognitive Wireless RAN Medium Access Control
              (MAC) and Physical Layer (PHY) specifications: Policies
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              Telecommunication/ICT Indicators Database - 2011",

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              DOI 10.1145/1963192.1963363, 2011.

              Huggler, J., "German villagers set up their own broadband
              network", June 2014,

Saldana, et al.               Informational                    [Page 33]
RFC 7962             Alternative Network Deployments         August 2016

   [Lysko]    Lysko, A., Masonta, M., Mofolo, M., Mfupe, L., Montsi, L.,
              Johnson, D., Mekuria, F., Ngwenya, D., Ntlatlapa, N.,
              Hart, A., Harding, C., and A. Lee, "First large TV white
              spaces trial in South Africa: A brief overview", 6th
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              creates its own mobile service", August 2013,

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              Communities Built Next-Generation Networks", Institute for
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              BMX6 for community wireless networks", In IEEE 8th
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              Neumann, A., Lopez, E., and L. Navarro, "Evaluation of
              mesh routing protocols for wireless community networks",
              Computer Networks, Vol. 93, Part 2, pp. 308-323, December
              2015, <>.

Saldana, et al.               Informational                    [Page 34]
RFC 7962             Alternative Network Deployments         August 2016

              New Mexico Department of Information Technology,
              "Broadband Guide for Electric Utilities", CTC Technology &
              Energy, Version 1, April 2015,

   [Norris]   Norris, P., "Digital Divide: Civic Engagement, Information
              Poverty, and the Internet Worldwide", Cambridge University
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              Sustainable Broadband Networks in Rural Areas", Technical
              Symposium at ITU Telecom World, pp. 135-140, October 2011.

   [NYTimes]  Gall, C. and J. Glanz, "U.S. Promotes Network to Foil
              Digital Spying", The New York Times, April 2014,

   [OLSR], "OLSR", 2016, <>.

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              for democratising wireless innovation", 2016,

   [OpenMesh] Open Mesh, "Open Mesh", 2016, <>.

   [Osmocom]  Open Source Mobile Communications (Osmocom), "Cellular
              Infrastructure", GPRS bitrates, 2016,

   [PAWS]     Sathiaseelan, A., Crowcroft, J., Goulden, M.,
              Greiffenhagen, C., Mortier, R., Fairhurst, G., and D.
              McAuley, "Public Access WiFi Service (PAWS)", Digital
              Economy All Hands Meeting, University of Aberdeen, October

   [PIE]      Pan, R., Natarajan, P., Baker, F., and G. White, "PIE: A
              Lightweight Control Scheme To Address the Bufferbloat
              Problem", Work in Progress, draft-ietf-aqm-pie-09, August

Saldana, et al.               Informational                    [Page 35]
RFC 7962             Alternative Network Deployments         August 2016

              Pietrosemoli, E., Zennaro, M., and C. Fonda, "Low cost
              carrier independent telecommunications infrastructure",
              Global Information Infrastructure and Networking
              Symposium, pp. 1-4, DOI 10.1109/GIIS.2012.6466655,
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              Range Networks, "Range Networks", 2016,

   [Redhook]  Red Hook WIFI, "Red Hook WIFI, a project of the Red Hook
              Initiative", 2016, <>.

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              Quispe-Taca, R., Linan-Benitez, L., and J. Simo-Reigadas,
              "A telemedicine WiFi network optimized for long distances
              in the Amazonian jungle of Peru", Proceedings of the 3rd
              Extreme Conference on Communication: The Amazon
              Expedition, Article No. 9, DOI 10.1145/2414393.2414402,

   [RFC1918]  Rekhter, Y., Moskowitz, B., Karrenberg, D., de Groot, G.,
              and E. Lear, "Address Allocation for Private Internets",
              BCP 5, RFC 1918, DOI 10.17487/RFC1918, February 1996,

   [RFC2328]  Moy, J., "OSPF Version 2", STD 54, RFC 2328,
              DOI 10.17487/RFC2328, April 1998,

   [RFC3168]  Ramakrishnan, K., Floyd, S., and D. Black, "The Addition
              of Explicit Congestion Notification (ECN) to IP",
              RFC 3168, DOI 10.17487/RFC3168, September 2001,

   [RFC3626]  Clausen, T., Ed. and P. Jacquet, Ed., "Optimized Link
              State Routing Protocol (OLSR)", RFC 3626,
              DOI 10.17487/RFC3626, October 2003,

   [RFC4271]  Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A
              Border Gateway Protocol 4 (BGP-4)", RFC 4271,
              DOI 10.17487/RFC4271, January 2006,

Saldana, et al.               Informational                    [Page 36]
RFC 7962             Alternative Network Deployments         August 2016

   [RFC6126]  Chroboczek, J., "The Babel Routing Protocol", RFC 6126,
              DOI 10.17487/RFC6126, April 2011,

   [RFC6297]  Welzl, M. and D. Ros, "A Survey of Lower-than-Best-Effort
              Transport Protocols", RFC 6297, DOI 10.17487/RFC6297, June
              2011, <>.

   [RFC7181]  Clausen, T., Dearlove, C., Jacquet, P., and U. Herberg,
              "The Optimized Link State Routing Protocol Version 2",
              RFC 7181, DOI 10.17487/RFC7181, April 2014,

   [RFC7567]  Baker, F., Ed. and G. Fairhurst, Ed., "IETF
              Recommendations Regarding Active Queue Management",
              BCP 197, RFC 7567, DOI 10.17487/RFC7567, July 2015,

   [Samanta]  Samanta, V., Knowles, C., Wagmister, J., and D. Estrin,
              "Metropolitan Wi-Fi Research Network at the Los Angeles
              State Historic Park", The Journal of Community
              Informatics, Vol. 4, No. 1, May 2008,

              Sathiaseelan, A., Rotsos, C., Sriram, C., Trossen, D.,
              Papadimitriou, P., and J. Crowcroft, "Virtual Public
              Networks", In IEEE 2013 Second European Workshop on
              Software Defined Networks (EWSDN) pp. 1-6,
              DOI 10.1109/EWSDN.2013.7, October 2013.

              Sathiaseelan, A. and J. Crowcroft, "LCD-Net: Lowest Cost
              Denominator Networking", ACM SIGCOMM Computer
              Communication Review, Vol. 43, No. 2, April 2013,

              Sathiaseelan, A., Mortier, R., Goulden, M., Greiffenhagen,
              C., Radenkovic, M., Crowcroft, J., and D. McAuley, "A
              Feasibility Study of an In-the-Wild Experimental Public
              Access WiFi Network", Proceedings of the Fifth ACM
              Symposium on Computing for Development, pp. 33-42,
              DOI 10.1145/2674377.2674383, 2014.

Saldana, et al.               Informational                    [Page 37]
RFC 7962             Alternative Network Deployments         August 2016

   [SDG]      United Nations, "Sustainable Development Goals",
              Sustainable Development Knowledge Platform, 2015,

   [Seither]  Seither, D., Koenig, A., and M. Hollick, "Routing
              performance of Wireless Mesh Networks: A practical
              evaluation of BATMAN advanced", IEEE 36th Conference on
              Local Computer Networks (LCN), pp. 897-904,
              DOI 10.1109/LCN.2011.6115569, October 2011.

   [Shi]      Shi, J., Gui, L., Koutsonikolas, D., Qiao, C., and G.
              Challen, "A Little Sharing Goes a Long Way: The Case for
              Reciprocal Wifi Sharing", HotWireless '15 Proceedings of
              the 2nd International Workshop on Hot Topics in Wireless,
              DOI 10.1145/2799650.2799652, September 2015.

   [Simo_a]   Simo-Reigadas, J., Morgado, E., Municio, E., Prieto-Egido,
              I., and A. Martinez-Fernandez, "Assessing IEEE 802.11 and
              IEEE 802.16 as backhaul technologies for rural 3G
              femtocells in rural areas of developing countries",
              Proceedings of EUCNC, 2014.

   [Simo_b]   Simo-Reigadas, J., Martinez-Fernandez, A., Ramos-Lopez,
              J., and J. Seoane-Pascual, "Modeling and Optimizing IEEE
              802.11 DCF for Long-Distance Links", IEEE Transactions on
              Mobile Computing, Vol. 9, Issue 6, pp. 881-896,
              DOI 10.1109/TMC.2010.27, 2010.

   [Simo_c]   Simo-Reigadas, J., Martinez-Fernandez, A., Osuna, P.,
              Lafuente, S., and J. Seoane-Pascual, "The Design of a
              Wireless Solar-Powered Router for Rural Environments
              Isolated from Health Facilities", IEEE Wireless
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   [Simo_d]   Simo-Reigadas, J., Municio, E., Morgado, E., Castro, E.,
              Martinez-Fernandez, A., Solorzano, L., and I. Prieto-
              Egido, "Sharing low-cost wireless infrastructures with
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              Build Their Own 4G Networks", November 2015,

Saldana, et al.               Informational                    [Page 38]
RFC 7962             Alternative Network Deployments         August 2016

   [Sprague]  Sprague, K., Grijpink, F., Manyika, J., Moodley, L.,
              Chappuis, B., Pattabiraman, K., and J. Bughin, "Offline
              and falling behind: Barriers to Internet adoption",
              McKinsey and Company, August 2014.

   [Tech]     Kazansky, B., "In Red Hook, Mesh Network Connects Sandy
              Survivors Still Without Power", November 2012,

              Baldwin, J., "TidePools: Social WiFi", Parsons, the New
              School for Design, Doctoral dissertation, Master thesis,
              2011, <

   [UN]       United Nations Statistics Division (UNSD), "Composition of
              macro geographical (continental) regions, geographical
              sub-regions, and selected economic and other groupings",
              October 2013, <

   [UNStats]  United Nations Statistics Division (UNSD), "Urban and
              total population by sex: 1996-2005", Table 6 - Demographic
              Yearbook 2005,

   [Vega_a]   Vega, D., Cerda-Alabern, L., Navarro, L., and R. Meseguer,
              "Topology patterns of a community network:",
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              Computing, Networking and Communications (WiMob), pp.
              612-619, DOI 10.1109/WiMOB.2012.6379139, October 2012.

   [Vega_b]   Vega, D., Baig, R., Cerda-Alabern, L., Medina, E.,
              Meseguer, R., and L. Navarro, "A technological overview of
              the community network", Computer Networks, Vol.
              93, Issue P2, pp. 260-278, December 2015,

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              Proceedings of the 4th ACM Workshop on Networked Systems
              for Developing Regions, Article No. 14,
              DOI 10.1145/1836001.1836015, 2010.

Saldana, et al.               Informational                    [Page 39]
RFC 7962             Alternative Network Deployments         August 2016

   [WiLD]     Patra, R., Nedevschi, S., Surana, S., Sheth, A.,
              Subramanian, L., and E. Brewer, "WiLDNet: Design and
              Implementation of High Performance WiFi Based Long
              Distance Networks", NSDI, Vol. 1, No. 1, pp. 1, April

   [WNDW]     WNDW, "Wireless Networking in the Developing World, 3rd
              Edition", The WNDW Project, 2013, <>.

              World Bank, "World Development Report 2016: Digital
              Dividends", Washington, DC: The World Bank, ISBN
              978-1-4648-0672-8, DOI 10.1596/978-1-4648-0671-1, 2016,

   [WSIS]     International Telecommunications Union, "Declaration of
              Principles. Building the Information Society: A global
              challenge in the new millennium", WSIS-03 / GENEVA / DOC /
              4-E, December 2003, <>.

   [YateBTS]  YateBTS, "YateBTS", 2016, <>.


   This work has been partially funded by the CONFINE European
   Commission project (FP7 - 288535).  Arjuna Sathiaseelan and Andres
   Arcia Moret were funded by the EU H2020 RIFE project (Grant Agreement
   no: 644663).  Jose Saldana was funded by the EU H2020 Wi-5 project
   (Grant Agreement no: 644262).

   The editor and the authors of this document wish to thank the
   following individuals who have participated in the drafting, review,
   and discussion of this memo: Panayotis Antoniadis, Paul M. Aoki,
   Roger Baig, Jaume Barcelo, Steven G. Huter, Aldebaro Klautau, Rohan
   Mahy, Vesna Manojlovic, Mitar Milutinovic, Henning Schulzrinne, Rute
   Sofia, and Dirk Trossen.

   A special thanks to the GAIA Working Group chairs Mat Ford and Arjuna
   Sathiaseelan for their support and guidance.

Saldana, et al.               Informational                    [Page 40]
RFC 7962             Alternative Network Deployments         August 2016


   Leandro Navarro
   U. Politecnica Catalunya
   Jordi Girona, 1-3, D6
   Barcelona  08034

   Phone: +34 93 401 6807

   Carlos Rey-Moreno
   University of the Western Cape
   Robert Sobukwe road
   Bellville  7535
   South Africa

   Phone: +27 (0)21 959 2562

   Ioannis Komnios
   Democritus University of Thrace
   Department of Electrical and Computer Engineering
   Kimmeria University Campus
   Xanthi 67100

   Phone: +306945406585

   Steve Song
   Network Startup Resource Center
   Lunenburg, Nova Scotia

   Phone: +1 902 529 0046

   David Lloyd Johnson
   Meraka, CSIR
   15 Lower Hope St
   Rosebank 7700
   South Africa

   Phone: +27 (0)21 658 2740

Saldana, et al.               Informational                    [Page 41]
RFC 7962             Alternative Network Deployments         August 2016

   Javier Simo-Reigadas
   Escuela Tecnica Superior de Ingenieria de Telecomunicacion
   Campus de Fuenlabrada
   Universidad Rey Juan Carlos

   Phone: +34 91 488 8428
   Fax:   +34 91 488 7500

Authors' Addresses

   Jose Saldana (editor)
   University of Zaragoza
   Dpt. IEC Ada Byron Building
   Zaragoza  50018

   Phone: +34 976 762 698

   Andres Arcia-Moret
   University of Cambridge
   15 JJ Thomson Avenue
   Cambridge  FE04
   United Kingdom

   Phone: +44 (0) 1223 763610

   Bart Braem
   Gaston Crommenlaan 8 (bus 102)
   Gent  9050

   Phone: +32 3 265 38 64

Saldana, et al.               Informational                    [Page 42]
RFC 7962             Alternative Network Deployments         August 2016

   Ermanno Pietrosemoli
   The Abdus Salam ICTP
   Via Beirut 7
   Trieste  34151

   Phone: +39 040 2240 471

   Arjuna Sathiaseelan
   University of Cambridge
   15 JJ Thomson Avenue
   Cambridge  CB30FD
   United Kingdom

   Phone: +44 (0)1223 763781

   Marco Zennaro
   The Abdus Salam ICTP
   Strada Costiera 11
   Trieste  34100

   Phone: +39 040 2240 406

Saldana, et al.               Informational                    [Page 43]