CoastalWiFi Technology

Wireless Mesh Network
A wireless mesh network (WMN) is a communications network made up of radio nodes organized in a mesh topology. Wireless mesh networks often consist of mesh clients, mesh routers and gateways. The mesh clients are often laptops, cell phones and other wireless devices while the mesh routers forward traffic to and from the gateways which may, but need not, connect to the Internet. The coverage area of the radio nodes working as a single network is sometimes called a mesh cloud. Access to this mesh cloud is dependent on the radio nodes working in harmony with each other to create a radio network. A mesh network is reliable and offers redundancy. When one node can no longer operate, the rest of the nodes can still communicate with each other, directly or through one or more intermediate nodes. The animation below illustrates how wireless mesh networks can self form and self heal. Wireless mesh networks can be implemented with various wireless technology including 802.11, 802.15, 802.16, cellular technologies or combinations of more than one type.

Network structure

Architecture

Wireless mesh architecture is a first step towards providing cost effective and dynamic high-bandwidth networks over a specific coverage area. Wireless mesh architectures infrastructure is, in effect, a router network minus the cabling between nodes. It's built of peer radio devices that don't have to be cabled to a wired port like traditional WLAN access points (AP) do. Mesh architecture sustains signal strength by breaking long distances into a series of shorter hops. Intermediate nodes not only boost the signal, but cooperatively make forwarding decisions based on their knowledge of the network, i.e. perform routing. Such an architecture may with careful design provide high bandwidth, spectral efficiency, and economic advantage over the coverage area.

Wireless mesh networks have a relatively stable topology except for the occasional failure of nodes or addition of new nodes. The path of traffic, being aggregated from a large number of end users, changes infrequently. Practically all the traffic in an infrastructure mesh network is either forwarded to or from a gateway, while in ad hoc networks or client mesh networks the traffic flows between arbitrary pairs of nodes. [1]

Management

This type of infrastructure can be decentralized (with no central server) or centrally managed (with a central server), [2] both are relatively inexpensive, and very reliable and resilient, as each node needs only transmit as far as the next node. Nodes act as routers to transmit data from nearby nodes to peers that are too far away to reach in a single hop, resulting in a network that can span larger distances. The topology of a mesh network is also reliable, as each node is connected to several other nodes. If one node drops out of the network, due to hardware failure or any other reason, its neighbors can quickly find another route using a routing protocol.

Applications

Mesh networks may involve either fixed or mobile devices. The solutions are as diverse as communication needs, for example in difficult environments such as emergency situations, tunnels, oil rigs, battlefield surveillance, high speed mobile video applications on board public transport or real time racing car telemetry. An important possible application for wireless mesh networks is VoIP. By using a Quality of Service scheme, the wireless mesh may support local telephone calls to be routed through the mesh.

Some current applications:

  • U.S. military forces are now using wireless mesh networking to connect their computers, mainly ruggedized laptops, in field operations.
  • Electric meters now being deployed on residences transfer their readings from one to another and eventually to the central office for billing without the need for human meter readers or the need to connect the meters with cables. [3]
  • The laptops in the One Laptop per Child program use wireless mesh networking to enable students to exchange files and get on the Internet even though they lack wired or cell phone or other physical connections in their area.
  • The 66-satellite Iridium constellation operates as a mesh network, with wireless links between adjacent satellites. Calls between two satellite phones are routed through the mesh, from one satellite to another across the constellation, without having to go through an earth station. This makes for a smaller travel distance for the signal, reducing latency, and also allows for the constellation to operate with far fewer earth stations that would be required for 66 traditional communications satellites.
Operation

The principle is similar to the way packets travel around the wired Internet— data will hop from one device to another until it reaches its destination. Dynamic routing algorithms implemented in each device allow this to happen. To implement such dynamic routing protocols, each device needs to communicate routing information to other devices in the network. Each device then determines what to do with the data it receives — either pass it on to the next device or keep it, depending on the protocol. The routing algorithm used should attempt to always ensure that the data takes the most appropriate (fastest) route to its destination.

References

  • ^ J. Jun, M.L. Sichitiu, "The nominal capacity of wireless mesh networks", in IEEE Wireless Communications, vol 10, 5 pp 8-14. October 2003
  • ^ S.M. Chen, P, Lin, D-W Huang, S-R Yang, "A study on distributed/centralized scheduling for wireless mesh network" in Proceedings of the 2006 International Conference on Wireless Communications and Mobile Computing, pp 599 - 604. Vancouver, British Columbia, Canada. 2006
  • ^ ZigBee.org Smart Energy Overview.
  • Integration













    How do I connect to the Internet?
    Connecting through your browser:
    1. Simply select and connect to the "Coastal WiFi" SSID or a Coastal WiFi partner SSID from the network list.
    2. Launch your Internet browser to access the Coastal WiFi Welcome page.
    Note: You may need to attempt to load a new URL to prompt the Boingo page.
    3. Log in using your Coastal Wifi username and password.
    (If it's a partner page, you'll probably simly need to click "Enter".)

    I am having trouble connecting on my laptop. Are there some basic things I can do to get online?
    • First, please restart your computer. Rebooting your laptop will often correct connection problems.
    • Be sure your Wi-Fi is turned on. Most computers have a Wi-Fi switch. If your computer does not have a Wi-Fi switch, please go to Internet options on your computer and verify your wireless LAN (WLAN) connection is enabled. If it is not enabled, right click and enable it.
    • Check your signal. Right click on the wireless icon in the system tray, select "View Wireless Networks" and select a network from the list presented.
    • If your computer indicates that it is connected, but the browser says "page cannot be displayed," then please verify your home page. Your home page may be set to your company intranet. Simply type any publicly-accessible web site into the address bar (such as https://www.coastalwifi.com) and you will be online or redirected to the signup page.
    • If you continue to have trouble, please contact Coastal WiFi Customer Support.


    I am having trouble connecting on my mobile device. Are there some basic things I can do to get online?
    • First, please check to be sure your Wi-Fi is "on" (if applicable). This option is usually located in the Settings menu.
    • Check your signal. From the Settings menu, select "Wi-Fi" and then choose "Coastal WiFi" SSID or a Coastal WiFi partner SSID from the network list (a sample list is below). Note: Some partner SSID networks do not support mobile devices..
    • If you continue to have trouble, please contact Coastal WiFi Customer Support.


    Is the Wi-Fi network affecting my cellphone data service (3G or 4G)?
    In short, no. It's technically impossible for Wi-Fi to interfere with cellular service, and it's actually illegal for anyone to interfere with cellular transmission. For the tech geeks among us, Wi-Fi and cellular data run on different frequencies, so they don't directly interfere with each other.

    Cellular service is also delivered over licensed spectrum, meaning that your service provider owns that specific frequency range, to ensure they can provide service without interference. It is possible for things like Bluetooth and microwaves to interfere with Wi-Fi, because they all use the same unlicensed spectrum frequencies. But none of those technologies can interfere with your cellphone Internet service.

    Can I use streaming video, video conference or VoIP (Voice over IP) on the CoastalWiFi Network?
    Absolutely! Coastal WiFi makes streaming video, VoIP calls and sending large files easy.
    Please note: Some of our partner Wi-Fi operators may restrict these data-intensive activities.