# Wireless Mesh Networks/Printable version

The current, editable version of this book is available in Wikibooks, the open-content textbooks collection, at
https://en.wikibooks.org/wiki/Wireless_Mesh_Networks

# Acknowledgements

Several people have been instrumental in allowing this project to be completed. We would like to thank the following people for contributing to this book:
* kgrr (discuss · email · contribs · logs · count) Initial outline
(please feel free to contribute and add yourself here)

# Introduction

Wireless networks nowadays are part of our everyday life, as witnessed by several features: the number of cell (mobile) phone subscriptions reached 7.3 billion in 2014., short-range radio technologies such as WiFi and Blue-tooth are widespread as well as radio frequency IDs (RFIDs).
In a search on Google for “next generation wireless network,” top hits mostly refer to evolutions of the cellular technology collectively named 4G, including technologies such as LTE (Long-Term Evolution), LTE Advanced, etc. These technologies are essentially aimed at improving quality of service (QoS) in cellular networks, especially that which concerns data services, which are expected to play an increasing role in connected world. The improvements are mostly obtained through advancements in the physical and medium access layer of the network protocol stack, for example, through extensive use of multi antenna systems, while the overall architecture of the cellular network is mostly unchanged. Thus, forthcoming 4G networks can be considered as an evolution of the well-established cellular network concept.
On the other hand, the class of networks (ad hoc networks, mesh networks, wireless sensor networks, vehicular networks, and opportunistic networks) that we collectively call next generation wireless networks are characterized by very different features compared to cellular networks:
* Cellular networks rely heavily on a wired, very expensive communication infrastructure – the network of cellular base stations – to perform communication; on the contrary, next generation wireless networks are characterized by a lightweight – or even absent – infrastructure.
* Cellular networks are based on the use of relatively long wireless links,with typical communication ranges in the order of up to a few kilometers; on the contrary, next generation wireless networks use short-range – in the order of a few tenths of meters, or hundreds of meters at most – wireless links.
* Cellular networks rely heavily on the presence of several centralization points, where servers are used for optimizing resource allocation and coordinate radio channel access between the different users in a cell and in adjacent cells; on the contrary, in next generation wireless networks, centralization points are typically lacking, and most network functionalities must be realized in a fully distributed, self-coordinated environment.
* Cellular networks are single-hop wireless networks, since a mobile terminal directly communicates with a base station in the vicinity; on the contrary, next generation wireless networks typically make extensive use of multi-hop communications to compensate for the short radio range and increase coverage.
| Header text | Cellular network | Wireless mesh network |
| Infrastructure | Yes | No, lightweight |
| Radio range | ≤ 2km | ≤ 300m |
| Centralization points | Yes | Mostly no |
| Type of communication | Single-hop | Multi-hop |
| Radio channel access | Coordinated | Mostly uncoordinated |
It is then evident that the class of emerging short-range wireless networks mentioned above displays striking differences with respect to traditional cellular networks, and that the design and realization of a network of this class entails defining brand-new network architectures and networking solutions spanning the entire network protocol stack. This explains our choice of naming the emergent class of short-range, multi-hop, decentralized wireless networks “next generation wireless networks.” Unless stated otherwise, in the remainder of this Wikibook we will use the term next generation wireless network exclusively to refer to a member of the class of short-range, multi-hop,decentralized wireless networks

## What it is actually ?

Wireless mesh network is a multi-hop, peer-to-peer wireless network in which mesh nodes connect with redundant interconnections and cooperate with one another to route packets inside the network.
Mesh nodes are small radio transmitters that function in the same way as a wireless router. Nodes use the common WiFi standards known as 802.11a, b and g to communicate wirelessly with other nodes.
Nodes are programmed with algorithms that tells them how to interact within the mesh network. The packets that carries informations travels across the network from point A to point B by hopping wirelessly from one mesh node to the next. The nodes automatically choose the quickest and safest path in a process known as dynamic routing. . There are two types of mesh network which are partial mesh and also full mesh. Partial mesh is mesh where not all the nodes are connected to each other meanwhile the full mesh is mesh where all the nodes are connected to each other

# References

* ↑ Pramis, Joshua (February 28, 2013). "Number of mobile phones to exceed world population by 2014". Digital Trends. Retrieved 8th March 2014. {{cite web}}: Check date values in: |accessdate= (help)
* ↑ "How Wireless Mesh Networks Work". How Stuff Works. Retrieved 8th March 2014. {{cite web}}: Check date values in: |accessdate= (help)
* ↑ "How Wireless Mesh Networks Work" (PDF). Motorola. Motorola. Retrieved 8th March 2014. {{cite web}}: Check date values in: |accessdate= (help)
* USENIX 2003 Annual Technical Conference, FREENIX Track — Paper "Building a Wireless Community Network in the Netherlands"
* "The innovation journey of wifi" authors Wolter Lemstra, Vic Hayes, John Groenewegen, Technische Universiteit Delft, The Netherlands Cambridge University Press 2010 ISBN:9780521199711

# Mesh network basics
## What is a Mesh Network?

A mesh network is a multiple path and multiple hop area wide network that are ideal for outdoor deployment. The mesh network consists of wireless networking devices (known as nodes)connecting within the range of the network nodes. Hence, it will form a decentralized networking as each node will only need to extend its own wireless range up to next node only. Each nodes are consistently communicating with each other in the local mesh network and are responsible for acting as a gateway for the packets to travel inside the mesh network.
A wireless mesh network have 3 characteristic of autonomic system which are
* Self forming / self organizing
* Self healing
* Self optimization
* Multi hop

### Self-forming / Self-organizing

New nodes joining the mesh network are transparently supported because meshing functions such as neighbours discovery and topology learning are implemented. Wireless routers rapidly detect the presence of new paths, thus enhancing the overall performance and coverage
The picture above shows the mesh networking self forming ability.
[1] A new node joins the mesh network
[2] Surrounding node are alerted to the new node presence and configuring on the fly to provide optimized routing for the packets [3] The new node are accepted in the mesh network

### Self-healing

A node may leave a mesh network due to unexpected circumstances such as failure in the networking devices, natural disaster/man made disaster and such.Therefore ,the mesh network are inherently designed to be more robust and resilient. There are many ways to do this such as make it a multi-path for packets to travel from one nodes to another (the amount of connections between 2 nodes is 2 or more) , decentralized connections and redundancy.
The picture above shows the mesh networking self healing ability
[1] One of the nodes in the mesh network are showing intermittent failures
[2] Surrounding nodes connected to the intermittent failing nodes are re-configuring to respond to the failing node
[3] The failing node when offline but the mesh network is still operating without downtime

### Self Optimization

The mesh network have the self optimization to enlarge the mesh coverage as large as possible, to minimizes the interferences and also to maximizes the bandwidth capacity of the mesh network.

### Multi-hop

Multi-hop connectivity allows several devices to access the network at once by relying on other mesh nodes without affecting the overall network performance. It will guarantees larger coverage zones and an enhancement of the network capacity. In fact, line-of-sight constraint no longer matters because the intermediate nodes relay the information to their neighbors on short wireless links using a reduced power transmission.
The picture above shows the multi-hop of mesh network in progress. [1] Node A want to access to the node D
[2] Node A sends wireless transmission links to nearby nodes
[3] Node B & node E forming link with node A
[4] Node E already found the node D forming mesh connection A-E-D
[5] Node B is still searching for node D but find node C instead
[6]Node C already found the node D forming mesh connection A-B-C-D

## Mesh vs. Point to Multi-point
### Reliability

In a classic wireless network, each node monitors that path between itself and an additional node. These networks are configured in a hierarchical fashion that ensures that each node uses a single connection path. The drawback to this approach is its lack of failure protection. If a node fails, the dedicated link is lost and the endpoint is unreachable until service is restored.
The establishment of multiple connection paths is a logical answer to this problem. Unfortunately, classic nodes lack the intelligent technology to select from alternate transmission paths.
Developers studied the idea of adding intelligence to each node to solve this problem. Such intelligence would track each available communication path and would logically select the best route. Added together, the multiplicity of nodes would create a mesh. This mesh would eliminate single points of failure. If one link went down,other network nodes would be alerted and could select an alternative node path. The design's self-healing nature would ensure that the network continued to operate. User access would be maintained as would productivity levels.
Today, the concept of intelligent mesh networks is a reality. Mesh is an increasingly applied network topology as researchers improve and enhance it, and businesses deploy and utilize it. Mesh has become the technology of choice for applications as diverse as securing military perimeters to regulating product flow down factory assembly lines to facilitating the intelligent navigation of one's morning commute.

### Coverage
## Links
### Access/Backhaul shared
## References
# History Highlights
## Philadelphia

Philadelphia wireless project
more stuff

## Wireless Leiden

Wireless Community Network established in 2002

## References

* ↑ "Wireless Philadelphia Blog".
* ↑ "Wireless Philadelphia FAQ".
* ↑ "Wireless Leiden website".

# Motivation

Below are listed of several reasons on why the "hacktivist" are keen on developing the mesh network technology

### Digital Divide

In rural area, there are often lack of Internet access. There are few projects in the world that tries to bridge the digital divide in the rural area.
(1) (India) SARI (Sustainable Access in Rural Area)
Mesh network created India to let the rural India have access to Internet
(2) (India) Aravind Teleophthalmology Kiosk
Mesh network created to let the patients self diagnosed himself in a kiosk and send the results to the doctors who maybe hundreds of kilometer away
(3) (Tibet) Dharamsala Wireless Mesh Network
In remote northern India region of Dharamsala where the Internet connection is patchy and unreliable, a group of networking experts helped the local people to set up the network.Using recycled PC parts and materials for antenna, they managed to connect over 2000 devices to the mesh networks itself.
(4) (Nepal) Nepal Wireless
In remote mountain of Nangi ,Mahabir Pun uses TV relay dishes to connect to Internet using the relays of mesh network. In May 2002, with help of university students, the Internet signal from Pokhara is sending Internet signal to Mohare

### Service Provider

(1) (South Africa) Mesh Potato by Village Telco
Mesh Potato is the wifi based mesh network services that provided data and free voice call to anyone in the network
(2) (Germany) BBNG / Citizen Broadband Network Company
In a population of few hundreds people, a small village Löwenstedt decided to take the slow patchy Internet connections by building their own Internet mesh network
(3) (United States) DBUIA / Doe Bay Internet User Associations
A group of neighbours frustrated by the Century Link patchy internet connections decided to establish their own Internet network

### Hobbyist

(1) (Greece)Free sharing culture inside the Greece community
(2) (Wall Street) Occupy Wall Street - Freedom Tower
The Internet we knew is under huge surveillance by NSA and now the Freedom tower is creating the other Internet which will provide freedom

### References

* ↑ "Sustainable Access in Rural Area".
* ↑ "Teleophthalmology" (PDF).
* ↑ "A Wireless Network for 'Little Lhasa'".
* ↑ "Mahabir Pun uses the internet to improve life in remote parts of Nepal".
* ↑ "Village Telco: A WiFi-based mesh network that offers voice and data services anywhere".
* ↑ "German Villaers Build Own Network".
* ↑ "How a group of neighbors created their own Internet service".
* ↑ "Strix: Government".
* ↑ "Mesh Networks: A Revolution in Wireless Connectivity".
* ↑ "Mesh Networks in Greece".
* ↑ "How Occupy Wall Street Is Building Its Own Internet".

# Social Impact
## Digital Divide
## References

* ↑ http://realneo.us/solution-to-the-digital-divide-in-East-Cleveland
* ↑ http://www.dailywireless.org/2007/02/13/bridging-the-digital-divide-2/

# Regulatory
## Licensed or Unlicensed
## References

* ↑ http://www.fcc.gov/cgb/consumerfacts/consumerdish.pdf

# Taxonomy of Mesh Types
## WAN, LAN or PAN?

Wide Area Network
Local Area Network
Processing Area Network
Storage Area Network

## References
# Design Parameters
# How many radios?

Meshes can be built with nodes that have a single radio, two radios and multiple radios. The number of radios in mesh nodes depends on the throughput and latency demands of the mesh network.

## One

Single radio wireless mesh nodes are low cost, but are limited by latency and scalability. The single radio node has take turns providing client access and transport to the network. The node is forced to store and forward and thus introduces latency.

## Two

Dual-radio wireless mesh nodes enhance the scalability and capacity of the wireless mesh network. One radio is used for client access and the other radio provides transport. Since the radios operate independently on two different frequencies, one radio can send while the other one is receiving. This reduces the latency from the access link to the transport link. However, when one node is relaying from one node to the next, a two radio node still needs to store and forward, which introduces latency.

## Three or More

A multi-radio wireless mesh node solves the latency problem for both the access link and the transport link. Multi-radio wireless nodes perform with very low latency and work well with real-time applications such as multimedia, voice and video applications. Because the throughput is related to throughput, multi-radio nodes address high density coverage areas, and can be used to aggregate traffic from single- and dual-radio wireless mesh nodes.

## Sample Deployments

Colgate University

## References

* ↑ "Solving the Wireless Mesh Multi-Hop Dilemma" (PDF).
* ↑ "When everything just meshes" (PDF). Cabling Connection. Feb/March 2006. {{cite web}}: Check date values in: |date= (help)
* ↑ "Colgate Brushes with Mesh Network". Alanat News. may 11, 2007. {{cite web}}: Check date values in: |date= (help)

# Transport
## 802.11a Wi-Fi
## ZigBee

ZigBee does not incorporate electric power lines into its technology therefore it is all wireless. ZigBee is very efficient, it can send up to 128 kilobits at a range of 250 feet. It is expected to be seen every from smoke detectors in your house to medical sensing devices. The best part is that it can function for a long time, on inexpensive batteries. Z-Wave also consists solely of wireless technology which is power efficient. It can send about 127 kilobits per second to a range of 100 feet. When you compare you would notice that Z-Wave and Insteon are very much similar. The only difference is that Insteon used electric power cables and Z-Wave doesn't.

## Others

proprietary microwave

## References

* ↑ "Improving Fairness in Multi-Hop Mesh Networks Using 802.11e" (PDF).

# RF Concerns
## Frequencies
## References

* ↑ "Minimum-Interference Channel Assignment in Multi-Radio Wireless Mesh Networks" (PDF). Stonybrook University.

# Applications
## The Killer Application
## Voice over IP

"Delivering Voice over IP over Mesh" (PDF).

## References
# Content
# Operations

There are few popular protocol operations used in the mesh network. Below are a few popular ones.
* Babel
http://www.pps.univ-paris-diderot.fr/~jch/software/babel/
* B.A.T.M.A.N.
http://www.open-mesh.org/projects/open-mesh/wiki
* L3 and L2
* BMX
http://bmx6.net/projects/bmx6
* OLSR
http://olsr.org/

## References
# Management
## Configuration

The goal of configuration management is too allow network managers track and modify the hardware and software configurations of devices in the network being managed.

## References
# Getting Power to the Node
# Planning Tools
## NetSim

NetSim is a popular tool for wireless network design and planning. The steps would be
Modeling and Simulation: Model the network scenario, and set up the protocol / device parameters. Then run the simulation Visualizing the simulation using the packet animator: This would show the flow of packets, movement of nodes etc Analyzing the results: Study the output statistics and then iterate if required

## References
# Mounting Options
# Testing Tools
## iPerf

iperf -s

## D-ITG

D-ITG http://traffic.comics.unina.it/software/ITG/

## References
# Meshes you can build
# Mesh network vendors
## BelAir
## Cisco

http://www.cisco.com

## Concentris Systems LLC

http://www.concentris-systems.com
Concentris Systems uses open standards wireless mesh networking technology to develop unique solutions that solve real life, challenging problems for rugged and severe-duty applications.
Concentris pioneered the versatile RapidLink network architecture that offers reliable, secure, high performance wireless mesh data networking. Easy to deploy and manage, RapidLink is ideal for situations where conventional data networking techniques are impractical or cost prohibitive.
Concentris Systems is focused upon making other people’s technology work better. The company provides a comprehensive suite of hardware and software products, coupled with training programs and hands-on service, for OEM and System Developer customers. Its toolkit is flexible and intuitive making it possible to create application-specific solutions in a surprisingly short time.
MIT graduate Tareq Hoque founded Concentris Systems. Before Concentris, Hoque was the president of Firetide, a successful early innovator in the field of mesh networking protocol and ad-hoc mesh networking. He was also president of Adtech Inc., the largest contributor to the Spirent Communications group of companies.
Concentris Systems LLC is a small, disadvantaged minority-owned business based in Honolulu, Hawaii.

## Firetide

http://www.firetide.com/

## Mesh Dynamics

http://www.meshdynamics.com
Incorporated in 2005, MeshDynamics is a privately held, profitable, U.S based corporation. Our headquarters are in Santa Clara, Northern California, USA.
Target Markets: Emerging outdoor enterprise wireless market opportunities such as those in mining, materials processing, military and border security, video surveillance, seismic oil exploration etc., place high demands on the wireless network infrastructure. Beyond data, critical real-time voice and video streams must also be supported, often in motion. Traditional wireless mesh architectures have been unable to support demands of this traffic, and thus have not penetrated these fast-developing markets to date.
Extensive testing by USAF, Battelle and others confirm that MeshDynamics' patented wireless mesh technology provides the highest throughput, low latency, and low jitter demanded by these applications through the use of dynamic channel allocation and a robust tree-based (deterministic and scalable) topology. High quality voice/video transport in demanding underground mine environments some up to 40 hops deep are in operation. No other mesh provider has demonstrated this level of scalability.
MeshDynamics mesh nodes have been installed in demanding applications requiring performance over multiple hops, noise free voice and video and rapid mesh formation with high speed mobility nodes. Applications include: municipal networking, underground mining and industrial, video surveillance, homeland security and public safety.

## Nortel

http://www.nortel.com

## RoamAD

http://www.roamad.com

## Strix

http://www.strixsystems.com

## ClearMesh Networks

http://www.clearmesh.com

## Tropos

{chapter stub}

## ValuePoint Networks

http://valuepointnet.com

# Bibliography

* http://research.microsoft.com/mesh/papers/multiradio.pdf Richard Draves Jitendra Padhye Brian Zill "Routing in Multi-Radio, Multi-Hop Wireless Mesh Networks" Microsoft Research, MobiCom 04, Sep 26-Oct 01, 2004 Philadelphia, PA
* http://www.infoworld.com/article/03/01/03/030103hnrashid_1.html
* Why all mesh products are not created equal. http://www.muniwireless.com/article/articleview/4537/1/2/Performance Analysis of Mesh Architectures

## Architectures

Review of three generation of mesh networking architectures http://wireless-straight-talk.blogspot.com/2006/11/talkin-bout-my-generation.html What is Third Generation Mesh?
Performance issues of First and Second Generation Mesh products http://www.google.com/search?q=cache:bMPl1QN_sI0J:www.dailywireless.org/2004/06/28/ugly-truth-about-mesh-networks Ugly Truths About Mesh Networks

## Vendors

Locust World An open source mishap offering for community networks as well as commercial offerings >http://www.locustworld.com LocustWorld
RoamAD For a software based approach to open architecture mesh networks for communities or ISPs. RoamAD also offers public safety networks capable of supporting video surveillance and mobile VoIP. http://www.roamad.com RoamAD
Mesh Networks (now Motorola) http://www.wi-fiplanet.com/columns/article.php/961951 http://www.wi-fiplanet.com/news/article.php/3436581
Metro Wi-Fi Deployments
Cambridge
"Municipal Mesh Network Protocols developed at MIT are helping the city of Cambridge to go wireless".

## Books

Held, Gilbert Wireless Mesh Networks

# Glossary

AC Alternating Current
API Application Programming Interface
CA Certificate Authority
CIDR Classless Inter-Domain Routing
DC Direct Current
DHCP Dynamic Host Configuration Protocol
DNS Domain Name System
FCC Federal Communications Commission
GPIO General Purpose Input/Output
GUI Graphical User Interface
HNA Host Network Announcement
I/O Input/Output
ICMP Internet Control Message Protocol
IP Internet Protocol
LED Light Emitting Diode
LOS Line Of Sight
MANET Mobile Ad Hoc Network
MID Mobile Internet Device
MPR Mote Processor Radio
NEMA National Electrical Manufacturers Association
NTP Network Time Protocol
NTSC/PAL National Television System Committee/Phase Altering Line OEM Original Equipment Manufacturer
OLSR Optimized Link State Routing
OLSRD Optimized Link State Routing Daemon
PoE Power Over Ethernet
PTT Push To Talk
PWM Pulse Width Modulation
RP-SMA Reverse Polarity-SubMiniature Version A
RF Radio Frequency
SSID Service Set Identifier
TC Topology Control
TCIP/IP Transmission Control Protocol/Internet Protocol
TOS Type Of Service
USB Universal Serial Bus
UTP Unshielded Twisted Pair
VANET Vehicular Ad Hoc Network
VPN Virtual Private Network
WAN Wide Area Network
WEP Wired Equivalency Privacy
WPA WiFi Protected Access

# Index

* 802.11a
* 802.11b
* 802.11g
* 802.11n
* 802.11s
* 802.16

### A

* Access
* Accounting and Billing
* Applicable Standards
* Applications

### B

* BelAir

### C

* Cisco
* Content
* Construction, Mounting Options

### D

Design Parameters

### E

* Economics
* Electric Power, Getting Power to the Node

### H

Handoffs, Mobility Handoffs History Highlights How many radios?

### I

ISO, What layers does it run on?

### K

Known Deployments

### L

Layers, What layers does it run on? Loops, preventing Topology Control

### M

* Management
* Mesh network basics
* Mesh network vendors
* Mesh routing protocols
* Mesh Timeline
* Meshes, Do it yourself Meshes you can build
* Meshes, Low Cost
* Meshes, Realtime
* Meshes, Types of
* Meshes, Taxonomy
* Meshes you can build
* Mobility Handoffs
* Motivation
* Mounting Options

### O

Operations

### P

Politics Power, Getting Power to the Node

### R

Regulatory RF concerns Routing protocols, mesh

### S

Social Impact Standards Applicable Standards

### T

Taxonomy of Mesh Types Timeline, Mesh Timeline Tools, Planning Tools, Survey Tools, Testing Topology Control Transport Types of Meshes

### V

Vendors, Mesh Network Vendors