Smartphone ad hoc networks (SPANs; also ''smart phone ad hoc networks'') are

wireless ad hoc network A wireless ad hoc network (WANET) or mobile ad hoc network (MANET) is a decentralized type of wireless network. The network is ad hoc because it does not rely on a pre-existing infrastructure, such as routers in wired networks or access points ...

s that use

smartphone A smartphone is a portable computer device that combines mobile telephone and computing functions into one unit. They are distinguished from feature phones by their stronger hardware capabilities and extensive mobile operating systems, whic ...

s. Once embedded with ad hoc networking technology, a group of smartphones in close proximity can together create an ad hoc network. Smart phone ad hoc networks use the existing hardware (primarily

Bluetooth Bluetooth is a short-range wireless technology standard that is used for exchanging data between fixed and mobile devices over short distances and building personal area networks (PANs). In the most widely used mode, transmission power is limit ...

and

Wi-Fi Wi-Fi () is a family of wireless network protocols, based on the IEEE 802.11 family of standards, which are commonly used for local area networking of devices and Internet access, allowing nearby digital devices to exchange data by radio w ...

) in commercially available smartphones to create peer-to-peer networks without relying on cellular carrier networks, wireless access points, or traditional network infrastructure. Wi-Fi SPANs use the mechanism behind Wi-Fi ad-hoc mode, which allows phones to talk directly among each other, through a transparent neighbor and route discovery mechanism. SPANs differ from traditional

hub and spoke A hub is the central part of a wheel that connects the axle to the wheel itself. Hub, The Hub, or hubs may refer to: Geography Pakistan * Hub Tehsil, Balochistan, an administrative division ** Hub, Balochistan, capital city of the tehsil * H ...

networks, such as

Wi-Fi Direct Wi-Fi Direct (formerly Wi-Fi Peer-to-Peer) is a Wi-Fi standard for peer-to-peer wireless connections that allows two devices to establish a direct Wi-Fi connection without an intermediary wireless access point, router, or Internet connection. Wi- ...

, in that they support multi-hop routing (ad hoc routing) and relays and there is no notion of a group leader, so peers can join and leave at will without destroying the network. Spans are useful under circumstances when the regular network is overloaded or unavailable, such as conferences, music festivals, or natural diasters, and have been popular in Australia and Latin America. They are popular with youth in the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five ma ...

as a way to save money, as data sent directly from device to device is free. SPANs started being used in

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in 2014 to bypass government restrictions on Internet usage, in the

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and 2019–20 Hong Kong protests, in 2015 in anti-government protests in

Russia Russia (, , ), or the Russian Federation, is a transcontinental country spanning Eastern Europe and Northern Asia. It is the largest country in the world, with its internationally recognised territory covering , and encompassing one-eigh ...

. They have also been used by protestors in Taiwan, Iran, and Syria.

Features

* Capable of going off-grid and enabling peer-to-peer communications without relying on cellular carrier networks, wireless access points, or traditional network infrastructure. * Optional Internet access through gateway devices, such as mobile hotspots in the mesh. * Optional stationary or portable infrastructures such as routers, mesh extenders, or other non-phone hardware. * Leverage the devices that people carry on their person and use every day. * Primarily use

Bluetooth Mesh Bluetooth Mesh is a computer mesh networking standard based on Bluetooth Low Energy that allows for many-to-many communication over Bluetooth radio. The Bluetooth Mesh specifications were defined in the Mesh Profile and Mesh Model specifications ...

or Wi-Fi, since the cellular spectrum is licensed and controlled by cellular providers and FCC regulations. * Set up and tear down are on-demand. Join and leave at will. * Routing protocol may be implemented at the Network Layer or Link Layer. * Often requires rooting a device and making modifications to the operating system, kernel, or drivers.

Threats to telcos

The ad hoc networking technology operating on

ad hoc mode, at the unlicensed

ISM band The ISM radio bands are portions of the radio spectrum reserved internationally for industrial, scientific and medical (ISM) purposes, excluding applications in telecommunications. Examples of applications for the use of radio frequency (RF) en ...

of 2.4 GHz may result in profit loss by cellular carriers since ISM band is free and unlicensed while cellular carriers operate on licensed band at 900 MHz, 1200 MHz, 1800 MHz, etc. This has the potential to threaten telecommunication operators (telcos). Smart phone

mobile ad hoc network A wireless ad hoc network (WANET) or mobile ad hoc network (MANET) is a decentralized type of wireless network. The network is ad hoc because it does not rely on a pre-existing infrastructure, such as routers in wired networks or access points ...

s can operate independently and allow communications among smart phones users without the need for any 3G or 4G LTE signals to be present. Wi-Fi ad hoc mode was first implemented on Lucent WaveLAN 802.11a/b on laptop computers. Since Wi-Fi is present and embedded in all smart phones today, this earlier technology was adapted for smartphones.

Usage

Smartphone ad hoc networks may be useful in situations that include: * developing nations where network infrastructure doesn't exist; * protests where government entities monitor or disable network infrastructure; * natural disasters or terrorist incidents where existing network infrastructure is overloaded, destroyed, or compromised; * temporary large-scale events such as festivals where a huge scale is needed for short period of time.

Real-life usage of smart phone ad hoc networks

* 2014 – in

following government restrictions on internet use, users use the technology to communicate * 2014 –

Hong Kong protests Hong Kong protests refers to various protests, demonstrations, or marches that have taken place in Hong Kong. It may refer to: Annual events * Hong Kong new year marches * Hong Kong 1 July marches * Memorials for the 1989 Tiananmen Square prot ...

calling for more democracy used FireChat to communicate * 2015 – Leaders of anti-government protests in Russia in December 2014 urged their followers to install FireChat * 2015 – By 2015, millions of teenagers and school children in the United States had started using smart phone ad hoc networks to chat and communicate, without the need for Wi-Fi or cellular signals. * 2019 – During the 2019–20 Hong Kong protests that started in opposition to a proposed modification of an extradition law,

Bridgefy Bridgefy is a Mexican software company with offices in Mexico and California, the United States, dedicated to developing mesh-networking technology for mobile apps. It was founded circa 2014 by Jorge Rios, after conceiving the idea while participat ...

, a smartphone ad hoc network app apparently running on

, was used to communicate during protests in a way that minimised tracking and interference by authorities.

Operating system

Apple Multipeer Connectivity

Apple Inc. Apple Inc. is an American multinational technology company headquartered in Cupertino, California, United States. Apple is the largest technology company by revenue (totaling in 2021) and, as of June 2022, is the world's biggest company ...

iPhones released with iOS version 7.0 and higher, multipeer connectivity APIs (application programmable interfaces) are enabled and provided to allow Apple iPhones to operate in peer-to-peer ad hoc mesh networking mode. This means iPhones can now talk to each other without using a cellular signal or connection. Currently, Apple uses multipeer to allow one to send photos and large files (up to GB) to peers. This application is called AirDrop and in 2017 had started gaining in popularity. With 700+ millions of iPhones being used globally, ad hoc peer-to-peer networks will gain pervasive presence almost instantly.

Android phone ad hoc networks

By merging the Linux Wireless Extension API with parts of the Android software stack, a modified version of Android can enable the ability to harness the ad hoc routing, communications and networking features of the onboard Wi-Fi chip. This empowers millions of Android phones (for example, Google Pixel phones) with ad hoc mesh connectivity and networking capabilities.

Software implementations

Software packages that implement smartphone ad hoc networks include

GPL The GNU General Public License (GNU GPL or simply GPL) is a series of widely used free software licenses that guarantee end users the four freedoms to run, study, share, and modify the software. The license was the first copyleft for general us ...

-licensed Serval Project over Bluetooth or WiFi; GPL-licensed

Commotion Wireless Commotion Wireless is an open-source wireless mesh network for electronic communication. The project was developed by the Open Technology Institute, and development included a $2 million grant from the United States Department of State in 2011 ...

; proprietary FireChat over Bluetooth,

over Bluetooth, and GPL-licensed Briar over Bluetooth or WiFi.

Device manufacturer support

* iOS Multipeer Connectivity Framework

References

{{Reflist, refs= {{cite news , last1= Koetsier , first1= John , title= Hong Kong Protestors Using Mesh Messaging App China Can't Block: Usage Up 3685% , date= 2019-09-02 , newspaper=

Forbes ''Forbes'' () is an American business magazine owned by Integrated Whale Media Investments and the Forbes family. Published eight times a year, it features articles on finance, industry, investing, and marketing topics. ''Forbes'' also r ...

, url= https://www.forbes.com/sites/johnkoetsier/2019/09/02/hong-kong-protestors-using-mesh-messaging-app-china-cant-block-usage-up-3685 , access-date= 2019-09-03 , archive-url= http://archive.wikiwix.com/cache/index2.php?url=https%3A%2F%2Fwww.forbes.com%2Fsites%2Fjohnkoetsier%2F2019%2F09%2F02%2Fhong-kong-protestors-using-mesh-messaging-app-china-cant-block-usage-up-3685 , archive-date= 2019-09-03 , url-status=live

External links

VolkFi

Smartphones A smartphone is a Mobile device, portable computer device that combines Mobile phone, mobile telephone and Mobile computing, computing functions into one unit. They are distinguished from feature phones by their stronger hardware capabilities ...

Mobile phones Wireless networking Radio resource management Politics and technology Internet-related activism Proposed telecommunications infrastructure