RFC 7962
Alternative Network Deployments: Taxonomy, Characterization, Technologies, and Architectures
Pages: 43
Informational
Informational
Part 2 of 2 – Pages 22 to 43
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 Guifi.net [Cerda-Alabern].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.
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 production. 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).6.2.1.1. 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.
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.
6.2.1.2. 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 (http://openbts.org) or OpenBSC
(http://openbsc.osmocom.org/trac/) 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
backhaul.
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.
6.2.1.3. 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.
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.6.2.1.3.1. 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.6.2.1.3.2. 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.
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 ranges. 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 ninux.org.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.7.1.2.1. 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].
7.1.2.2. Mesh Routing Protocols
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 nodes. 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 networks. 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.
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.
Some specialized services have been specifically developed for
Alternative Networks:
o Inter-network peering/VPNs
(e.g., https://wiki.freifunk.net/IC-VPN).
o Community-oriented portals (e.g., http://tidepools.co/).
o Network monitoring/deployment/maintenance platforms.
o VoIP sharing between networks, allowing cheap calls between
countries.
o Sensor networks and citizen science built by adding sensors to
devices.
o Community radio/TV stations.
Other services (e.g., local wikis as used in community portals; see
https://localwiki.org) 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.
8. Informative References
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[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, <https://ilsr.org/wp-content/uploads/downloads/2016/04/ rs-fiber-report-2016.pdf>. [Cash] Cash, C., "CO-MO'S D.I.Y. Model for Building Broadband", National Rural Electric Cooperative Association (NRECA), November 2015, <http://remagazine.coop/co-mo-broadband/>. [Cerda-Alabern] Cerda-Alabern, L., "On the topology characterization of Guifi.net", Proceedings of the IEEE 8th International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob), pp. 389-396, DOI 10.1109/WiMOB.2012.6379103, October 2012. [CoDel] Nichols, K., Jacobson, V., McGregor, A., and J. Iyengar, "Controlled Delay Active Queue Management", Work in Progress, draft-ietf-aqm-codel-04, June 2016. [Couto] De Couto, D., Aguayo, D., Bicket, J., and R. Morris, "A high-throughput path metric for multi-hop wireless routing", Wireless Networks, Vol. 11, Issue 4, pp. 419-434, DOI 10.1007/s11276-005-1766-z, July 2005. [Endaga] Alleven, M., "Endaga raises $1.2M to help it bring cellular to remote villages", FierceWireless Tech News, December 2014, <http://www.fiercewireless.com/tech/story/ endaga-raises-12m-help-it-bring-cellular-remote- villages/2014-12-03>. [Everylayer] Everylayer, Inc. (formerly Volo Broadband), "Everylayer", 2015, <http://www.everylayer.com/>. [Fon] Fon, "Fon is the Global WiFi Network", 2014, <https://corp.fon.com/en>. [GAIA] Internet Research Task Force, "Charter: Global Access to the Internet for All Research Group (GAIA)", 2016, <https://irtf.org/gaia>.
[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 Conference on Pervasive Computing and Communications Workshops (PERCOM Workshops), pp. 588-593, DOI 10.1109/PERCOMW.2010.5470505, 2010. [Heimerl] Heimerl, K., Shaddi, H., Ali, K., Brewer, E., and T. Parikh, "Local, sustainable, small-scale cellular networks", In ICTD 2013, Cape Town, South Africa, DOI 10.1145/2516604.2516616, 2013. [IEEE] Institute of Electrical and Electronics Engineers (IEEE), "IEEE Standards Association", <https://standards.ieee.org/>. [IEEE.802.11] 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", IEEE 802.11-2012, DOI 10.1109/ieeestd.2012.6178212, April 2012, <http://standards.ieee.org/getieee802/ download/802.11-2012.pdf>. [IEEE.802.11AF] 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 5: Television White Spaces (TVWS) Operation", IEEE 802.11af-2013, DOI 10.1109/ieeestd.2014.6744566, February 2014, <http://standards.ieee.org/getieee802/ download/802.11af-2013.pdf>. [IEEE.802.16] IEEE, "IEEE Standard for Information technology - Telecommunications and information exchange between systems - Broadband wireless metropolitan area networks (MANs) - IEEE Standard for Air Interface for Broadband Wireless Access Systems", IEEE 802.16-2012, DOI 10.1109/ieeestd.2012.6272299, August 2012, <http://standards.ieee.org/getieee802/ download/802.16-2012.pdf>.
[IEEE.802.22] 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 and procedures for operation in the TV Bands", IEEE 802.22-2011, DOI 10.1109/ieeestd.2011.5951707, July 2011, <http://ieeexplore.ieee.org/servlet/ opac?punumber=5951705>. [IFAD2011] International Fund for Agricultural Development (IFAD), "Rural Poverty Report 2011", ISBN 978-92-9072-200-7, 2011. [InternetStats] Internet World Stats, "World Internet Users and 2015 Population Stats", <http://www.internetworldstats.com/stats.htm>. [ITU2011] International Telecommunication Union, "World Telecommunication/ICT Indicators Database - 2011", <http://www.itu.int/en/ITU-D/Statistics/Pages/ publications/wtid.aspx>. [Johnson_a] Johnson, D. and K. Roux, "Building Rural Wireless Networks: Lessons Learnt and Future Directions", In Proceedings of the ACM workshop on Wireless networks and systems for developing regions, pp. 17-22, DOI 10.1145/1410064.1410068, 2008. [Johnson_b] Johnson, D., Pejovic, V., Belding, E., and G. van Stam, "Traffic Characterization and Internet Usage in Rural Africa", In Proceedings of the 20th International Conference Companion on World Wide Web, pp. 493-502, DOI 10.1145/1963192.1963363, 2011. [Lowenstedt] Huggler, J., "German villagers set up their own broadband network", June 2014, <http://www.telegraph.co.uk/news/worldnews/europe/ germany/10871150/ German-villagers-set-up-their-own-broadband-network.html>.
[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 International Congress on Ultra Modern Telecommunications and Control Systems and Workshops (ICUMT), pp. 407-414, DOI 10.1109/ICUMT.2014.7002136, October 2014. [Mathee] Mathee, K., Mweemba, G., Pais, A., Stam, V., and M. Rijken, "Bringing Internet connectivity to rural Zambia using a collaborative approach", International Conference on Information and Communication Technologies and Development, pp. 1-12, DOI 10.1109/ICTD.2007.4937391, 2007. [McMahon] McMahon, R., Gurstein, M., Beaton, B., Donnell, S., and T. Whiteducke, "Making Information Technologies Work at the End of the Road", Journal of Information Policy, Vol. 4, pp. 250-269, DOI 10.5325/jinfopoli.4.2014.0250, 2014. [Meraki] Cisco Systems, "Meraki", 2016, <https://www.meraki.com/>. [Mexican] Varma, S., "Ignored by big companies, Mexican village creates its own mobile service", August 2013, <http://timesofindia.indiatimes.com/world/rest-of-world/ Ignored-by-big-companies-Mexican-village-creates-its-own- mobile-service/articleshow/22094736.cms>. [Mitchell] Mitchell, C., "Broadband At the Speed of Light: How Three Communities Built Next-Generation Networks", Institute for Local Self-Reliance (ILSR), April 2012, <http://ilsr.org/ wp-content/uploads/2012/04/muni-bb-speed-light.pdf>. [Neumann_a] Neumann, A., Lopez, E., and L. Navarro, "An evaluation of BMX6 for community wireless networks", In IEEE 8th International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob), pp. 651-658, DOI 10.1109/WiMOB.2012.6379145, 2012. [Neumann_b] 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, <http://dx.doi.org/10.1016/j.comnet.2015.07.018>.
[NewMexico] New Mexico Department of Information Technology, "Broadband Guide for Electric Utilities", CTC Technology & Energy, Version 1, April 2015, <http://www.doit.state.nm.us/broadband/reports/ NMBBP_FiberGuide_ElectricUtilities.pdf>. [Norris] Norris, P., "Digital Divide: Civic Engagement, Information Poverty, and the Internet Worldwide", Cambridge University Press, ISBN 0521807514, 2001. [Nungu] Nungu, A., Knutsson, B., and B. Pehrson, "On Building 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, <http://www.nytimes.com/2014/04/21/us/ us-promotes-network-to-foil-digital-spying.html?_r=1>. [OLSR] OLSR.org, "OLSR", 2016, <http://www.olsr.org/>. [Openair] OpenAirInterface, "OpenAirInterface: 5G software alliance for democratising wireless innovation", 2016, <http://www.openairinterface.org/>. [OpenMesh] Open Mesh, "Open Mesh", 2016, <http://www.open-mesh.com/>. [Osmocom] Open Source Mobile Communications (Osmocom), "Cellular Infrastructure", GPRS bitrates, 2016, <https://osmocom.org/projects/osmopcu/wiki/GPRS_bitrates>. [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 2012. [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 2016.
[Pietrosemoli] 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, December 2012. [Rangenetworks] Range Networks, "Range Networks", 2016, <http://www.rangenetworks.com>. [Redhook] Red Hook WIFI, "Red Hook WIFI, a project of the Red Hook Initiative", 2016, <http://redhookwifi.org/>. [Rey] Rey-Moreno, C., Bebea-Gonzalez, I., Foche-Perez, I., 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, 2011. [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, <http://www.rfc-editor.org/info/rfc1918>. [RFC2328] Moy, J., "OSPF Version 2", STD 54, RFC 2328, DOI 10.17487/RFC2328, April 1998, <http://www.rfc-editor.org/info/rfc2328>. [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, <http://www.rfc-editor.org/info/rfc3168>. [RFC3626] Clausen, T., Ed. and P. Jacquet, Ed., "Optimized Link State Routing Protocol (OLSR)", RFC 3626, DOI 10.17487/RFC3626, October 2003, <http://www.rfc-editor.org/info/rfc3626>. [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, <http://www.rfc-editor.org/info/rfc4271>.
[RFC6126] Chroboczek, J., "The Babel Routing Protocol", RFC 6126, DOI 10.17487/RFC6126, April 2011, <http://www.rfc-editor.org/info/rfc6126>. [RFC6297] Welzl, M. and D. Ros, "A Survey of Lower-than-Best-Effort Transport Protocols", RFC 6297, DOI 10.17487/RFC6297, June 2011, <http://www.rfc-editor.org/info/rfc6297>. [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, <http://www.rfc-editor.org/info/rfc7181>. [RFC7567] Baker, F., Ed. and G. Fairhurst, Ed., "IETF Recommendations Regarding Active Queue Management", BCP 197, RFC 7567, DOI 10.17487/RFC7567, July 2015, <http://www.rfc-editor.org/info/rfc7567>. [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, <http://ci-journal.net/index.php/ciej/article/ viewArticle/427>. [Sathiaseelan_a] 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_b] Sathiaseelan, A. and J. Crowcroft, "LCD-Net: Lowest Cost Denominator Networking", ACM SIGCOMM Computer Communication Review, Vol. 43, No. 2, April 2013, <http://dx.doi.org/10.1145/2479957.2479966>. [Sathiaseelan_c] 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.
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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.
Contributors
Leandro Navarro U. Politecnica Catalunya Jordi Girona, 1-3, D6 Barcelona 08034 Spain Phone: +34 93 401 6807 Email: leandro@ac.upc.edu Carlos Rey-Moreno University of the Western Cape Robert Sobukwe road Bellville 7535 South Africa Phone: +27 (0)21 959 2562 Email: crey-moreno@uwc.ac.za Ioannis Komnios Democritus University of Thrace Department of Electrical and Computer Engineering Kimmeria University Campus Xanthi 67100 Greece Phone: +306945406585 Email: ikomnios@ee.duth.gr Steve Song Network Startup Resource Center Lunenburg, Nova Scotia Canada Phone: +1 902 529 0046 Email: stevesong@nsrc.org David Lloyd Johnson Meraka, CSIR 15 Lower Hope St Rosebank 7700 South Africa Phone: +27 (0)21 658 2740 Email: djohnson@csir.co.za
Javier Simo-Reigadas Escuela Tecnica Superior de Ingenieria de Telecomunicacion Campus de Fuenlabrada Universidad Rey Juan Carlos Madrid Spain Phone: +34 91 488 8428 Fax: +34 91 488 7500 Email: javier.simo@urjc.esAuthors' Addresses
Jose Saldana (editor) University of Zaragoza Dpt. IEC Ada Byron Building Zaragoza 50018 Spain Phone: +34 976 762 698 Email: jsaldana@unizar.es Andres Arcia-Moret University of Cambridge 15 JJ Thomson Avenue Cambridge FE04 United Kingdom Phone: +44 (0) 1223 763610 Email: andres.arcia@cl.cam.ac.uk Bart Braem iMinds Gaston Crommenlaan 8 (bus 102) Gent 9050 Belgium Phone: +32 3 265 38 64 Email: bart.braem@iminds.be
Ermanno Pietrosemoli The Abdus Salam ICTP Via Beirut 7 Trieste 34151 Italy Phone: +39 040 2240 471 Email: ermanno@ictp.it Arjuna Sathiaseelan University of Cambridge 15 JJ Thomson Avenue Cambridge CB30FD United Kingdom Phone: +44 (0)1223 763781 Email: arjuna.sathiaseelan@cl.cam.ac.uk Marco Zennaro The Abdus Salam ICTP Strada Costiera 11 Trieste 34100 Italy Phone: +39 040 2240 406 Email: mzennaro@ictp.it