The Wireless Internet Service Provider System (WISP) is an integrated Metropolitan Area Network (MAN) system of connecting customers to the Internet.
Wireless data links take place of dedicated leased lines where the leased line connection is not possible or too expensive. Basic requirements for using wireless data links are:
• Customers are located within 15 miles or 24km radius around the central site.
• Direct Line of Sight between Customer location and the central antenna.
• Use of the 900MHz, 2.4GHz, 5.2GHz or 5.8GHz frequencies (Unlicensed Band) according to the local regulations. In some countries obtaining a special license might be required.
• Use of the 2.3MHz to 2.7MHz, 3.4 to 3.6MHz and 4.9GHz frequencies (Licensed Band) according to the local regulations.
How to Start a Wireless ISP
The following material is meant to help you with what steps are necessary to start a Wireless Internet Service Provision System (WISP). Under WISP we understand an integrated Metropolitan Area Network (MAN) system of connecting customers to the Internet. High-speed wireless datalinks are used to provide Internet access on a point-to-point and point-to-multipoint basis for companies, governmental organizations, schools, universities and other institutions having Local Area Networks (LAN).
First of all, you should answer the main question:
Do you have a permanent (256kbps or faster) Internet connection?
If your answer to this question is YES, then you can proceed with your plan of becoming a Wireless ISP and follow the suggestions given in this material.
Should your answer be NO, then please understand you must first have a dedicated Internet Connection.
Those, who have internet access, can start finding answers to following questions:
Q1: Do you expect to have the necessary customer basis for a Wireless ISP System in your area?
A: Generally speaking, you should consider the WISP just like permanent leased line connections to the customers, but at a higher speed and lower cost. Please read about What is a WISP, and what not*.
*What is a WISP, and what not? The Wireless ISP System is a fixed wireless service between the central node and the client. It is not a mobile service, at least in most of the cases, because:
— Direct line of sight is required between the central node and the client, and
— Low power radios and high gain antennas are used for the wireless links. The Wireless ISP System is a land service operating as a Metropolitan Area Network with cells of 15 miles or 24 km. radius. It is not a Satellite ISP System. The Wireless ISP System is a bi-directional service, where both the client and the central node is sending and receiving data. It is not a transmitter – receiver system, every node does both tasks.
Q2: What are the regulations and rules for using the Licensed and Unlicensed Frequency wireless data communication equipment in your country?
A: In most cases you will need to get a permission to use the Unlicensed frequency (900MHz, 2.4GHz, 5GHz), but sometimes a license might be necessary for providing wireless service and use Licensed frequency.
Q3: Is the setup of wireless connections technically possible?
A: The system operates on a point to multi-point basis, and consists of a base station and several client nodes within 15 miles or 24 km. radius around it. The client nodes connect to the base unit over wireless links. Therefore, direct line of sight* is required between the client antenna and the base station antenna in order to establish the wireless connection.
*Direct line of Sight between two points is ability to see from one point the other point without any physical obstacles, like trees, leaves of the trees, branches of the trees, buildings, walls, roof constructions, hills, forests.
For longer distances, there can be problems with ensuring the line of sight due to the Earth curvature. For example, direct line of sight can be ensured between two points located between each other at a distance of 40km, if they are risen at 17m height. Please use the Distance Calculation Utility provided by Google Earth
Q4: What would be the best location for the Base Station?
A: You should consider a high location for installing the central antenna, so that all your client antennas could see the central antenna without any obstacles, i.e., they should have direct line of sight with the central antenna. Some suggestions for best locations of Base station antenna could be:
• Top of a high building somewhere in the city
• Top of a building located on a hill
• high tower (TV or some communication tower)
It is very important, that you can find such a location, where the Base Station antenna and the Base Radio Unit can be installed closely, e.g.,
• antenna on the roof of a building and base unit in the attic,
• antenna on a communication tower and base unit in a weather-proof box attached to that tower.
Although a low loss cable is used for connecting the antenna to the Base Radio Unit, its length should be as short as possible to avoid signal loss. The cable length should not exceed 9m without an amplifier. Do not plan to have longer cables, or to substitute low loss cables with some lower quality ones – your system won’t work!
Also, you will need to organize 110V or 220V power to the base unit, UPS is recommended
Q5: What equipment and preparations are needed for the Client Site?
A: For client site you will need to consider where to mount the directional parabolic grid antenna, where to put the wireless router and how to connect it to the client’s LAN and to 110V or 220V power. Again, you should find a place for the router, where the distance to the antenna is minimal. You should better consider using a shorter antenna cable and extend the LAN’s cable [PoE] to the place where you install the Switch or router.
Typical locations for the client antenna are:
• middot roof of the building, antenna attached the pipe holding TV antenna, or a specially installed pipe for your antenna,
• wall of the building
• window frame, antenna mount attached to the window frame of a room, where the wireless router is located.
Q6: How to install and configure the central site with the base unit and omni-directional antenna?
A: When the place has been found for the omni-directional antenna and for the base unit, the antenna should be mounted and cable connected to the antenna and to the base unit. Connectors outside the rooms should be protected using weatherproof rubber material tape to avoid moisture coming into the connectors. Ordinary electrical tape should be put over the rubber protecting tape. Electrical tape alone does not protect the cable connections hermetically enough. Within a few months moisture will be inside the cable connections, and the quality of your system will be degraded.
What concerns the minimum required configuration of the base unit, you should choose the frequency your system will be operated at, the basic data rate, and the system identifier. Only clients having the same radio settings will be able to work with your base unit. More options for configuring the base unit are explained in the manual for it
Q7: How to install and configure the client sites with the wireless router and directional antenna?
A: The directional antenna should be mounted vertically polarized, since the base unit (omni-directional) antenna is vertically polarized. The same rules as described above are applied for connecting and protecting the cables. The antenna should be pointed directly to the central antenna. Performing link test between the base unit and client router should do final adjustment.
Q8: What are possible TCP/IP network configurations for the WISP system?
Usually the client LANs may have the TCP/IP protocol running with unregistered IP addresses. You may leave the addresses as they are and take one free address from the client’s network for the Ethernet interface of Wireless Router. Alternatively, you may provide the client with a subnet from the network addresses that you have as an ISP. The Ethernet address of wireless router is default gateway for all hosts on the clients LAN.
The Wireless LAN is another TCP/IP network, since it is separated from the client networks by routers. An IP subnet should be assigned to the hosts on the wireless LAN including the wireless interfaces of all client routers and the base unit, one address to each of them. The following should be considered when setting up default gateways for all client routers and the bridge.
• If the wireless network is connected to your network, i.e., the base unit’s Ethernet port is connected to your/ISP’s network cable, then the default gateway is that host/router, what is used for your network. Note that the base unit is a bridge and not a router, therefore it does not serve as a TCP/IP gateway. See the possible setup diagram.
• If you use one of the wireless routers as a gateway to connect the wireless network to your/ISP’s network, then use the radio interface’s IP address as the default gateway for all client routers and the base unit. See the possible setup diagram.
Use traceroute and ping to test how well you have done the TCP/IP configurations. Read textbooks and RFCs once more if you have forgotten the basic things about IP networking and routing. But remember, that nothing will help you to get pings going between two hosts and further, if you have problems with the radio connection. It’s just like if you have cabling problems, you cannot ping.
I will be reviewing some of the best WISP solutions on the next blog