Global Access to the Internet for All                    J. Saldana, Ed.
Internet-Draft                                    University of Zaragoza
Intended status: Informational                            A. Arcia-Moret
Expires: January 2, 2016                         University of Cambridge
                                                                B. Braem
                                                                  iMinds
                                                         E. Pietrosemoli
                                                                    ICTP
                                                         A. Sathiaseelan
                                                 University of Cambridge
                                                              M. Zennaro
                                                        Abdus Salam ICTP
                                                            July 1, 2015


     Alternative Network Deployments.  Taxonomy, characterization,
                     technologies and architectures
           draft-irtf-gaia-alternative-network-deployments-01

Abstract

   This document presents a taxonomy of "Alternative Network
   deployments", and a set of definitions and shared properties.  It
   also discusses the technologies employed in these network
   deployments, and their differing architectural characteristics.

   The term "Alternative Network Deployments" includes a set of network
   access models that have emerged in the last decade with the aim of
   bringing Internet connectivity to people, using topological,
   architectural and business models different from the so-called
   "traditional" ones, where a company deploys or leases the network
   infrastructure for connecting the users, who pay a subscription fee
   to be connected and make use of it.

   Several initiatives throughout the world have built large scale
   alternative Networks, using predominantly wireless technologies
   (including long distance) due to the reduced cost of using the
   unlicensed spectrum.  Wired technologies such as fiber are also used
   in some of these alternate networks.  There are several types of
   alternate networks: community networks, which are self-organized and
   decentralized networks wholly owned by the community; networks owned
   by individuals who act as 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, and finally there are networks that provide connectivity
   by sharing wireless resources of the users.





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   The emergence of these networks can be motivated by different causes
   such as the reluctance, or the impossibility, of network operators to
   provide wired and cellular infrastructures to rural/remote areas.  In
   these cases, the networks have self sustainable business models that
   provide more localized communication services as well as Internet
   backhaul support through peering agreements with traditional network
   operators.  Some other times, networks are built as a complement and
   an alternative to commercial Internet access provided by
   "traditional" network operators.

   The present classification considers different existing network
   models such as Community Networks, open wireless services, user-
   extensible services, traditional local Internet Service Providers
   (ISPs), new global ISPs, etc.  Different criteria are used in order
   to build a classification as e.g., the ownership of the equipment,
   the way the network is organized, the participatory model, the
   extensibility, if they are driven by a community, a company or a
   local stakeholder (public or private), etc.

   According to the developed taxonomy, a characterization of each kind
   of network is presented in terms of specific network characteristics
   related to architecture, organization, etc.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
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   Drafts is at http://datatracker.ietf.org/drafts/current/.

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   This Internet-Draft will expire on January 2, 2016.

Copyright Notice

   Copyright (c) 2015 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
   (http://trustee.ietf.org/license-info) in effect on the date of



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   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   4
     1.1.  Traditional networks  . . . . . . . . . . . . . . . . . .   5
     1.2.  Criteria for the classification of Alternative Networks .   5
       1.2.1.  Commercial model / promoter . . . . . . . . . . . . .   5
       1.2.2.  Goals and motivation  . . . . . . . . . . . . . . . .   6
       1.2.3.  Administrative model  . . . . . . . . . . . . . . . .   6
       1.2.4.  Technologies employed . . . . . . . . . . . . . . . .   6
       1.2.5.  Typical scenarios . . . . . . . . . . . . . . . . . .   7
   2.  Classification of Alternative Networks  . . . . . . . . . . .   7
     2.1.  Community Networks  . . . . . . . . . . . . . . . . . . .   7
       2.1.1.  Free Networks . . . . . . . . . . . . . . . . . . . .   9
     2.2.  Wireless Internet Service Providers WISPs . . . . . . . .  10
     2.3.  Shared infrastructure model . . . . . . . . . . . . . . .  11
     2.4.  Crowdshared approaches, led by the people and third party
           stakeholders  . . . . . . . . . . . . . . . . . . . . . .  12
     2.5.  Testbeds for research purposes  . . . . . . . . . . . . .  15
   3.  Scenarios where Alternative Networks are deployed . . . . . .  15
     3.1.  Digital Divide and Alternative Networks . . . . . . . . .  15
     3.2.  Urban vs. rural areas . . . . . . . . . . . . . . . . . .  17
     3.3.  Gap between demanded and provided communications services  18
     3.4.  Topology patterns followed by Alternative Networks  . . .  18
   4.  Technologies employed . . . . . . . . . . . . . . . . . . . .  19
     4.1.  Wired . . . . . . . . . . . . . . . . . . . . . . . . . .  19
     4.2.  Wireless  . . . . . . . . . . . . . . . . . . . . . . . .  19
       4.2.1.  Antennas  . . . . . . . . . . . . . . . . . . . . . .  19
       4.2.2.  Physical link length  . . . . . . . . . . . . . . . .  20
         4.2.2.1.  Line-of-Sight . . . . . . . . . . . . . . . . . .  20
         4.2.2.2.  Transmitted and Received Power  . . . . . . . . .  20
       4.2.3.  Media Access Control (MAC) Protocols for Wireless
               Links . . . . . . . . . . . . . . . . . . . . . . . .  21
         4.2.3.1.  802.11 (Wi-Fi)  . . . . . . . . . . . . . . . . .  21
         4.2.3.2.  GSM . . . . . . . . . . . . . . . . . . . . . . .  23
         4.2.3.3.  Dynamic Spectrum  . . . . . . . . . . . . . . . .  23
   5.  Upper layers  . . . . . . . . . . . . . . . . . . . . . . . .  24
     5.1.  Layer 3 . . . . . . . . . . . . . . . . . . . . . . . . .  24
       5.1.1.  IP addressing . . . . . . . . . . . . . . . . . . . .  24
       5.1.2.  Routing protocols . . . . . . . . . . . . . . . . . .  25
         5.1.2.1.  Traditional routing protocols . . . . . . . . . .  25
         5.1.2.2.  Mesh routing protocols  . . . . . . . . . . . . .  25



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     5.2.  Transport layer . . . . . . . . . . . . . . . . . . . . .  26
       5.2.1.  Traffic Management when sharing network resources . .  26
       5.2.2.  Multi-hop issues  . . . . . . . . . . . . . . . . . .  26
     5.3.  Services provided . . . . . . . . . . . . . . . . . . . .  27
       5.3.1.  Intranet services . . . . . . . . . . . . . . . . . .  27
       5.3.2.  Access to the Internet  . . . . . . . . . . . . . . .  28
         5.3.2.1.  Web browsing proxies  . . . . . . . . . . . . . .