1. Basic Description of Wireless ISP System
MikroTik Wireless Internet Service Provider Systems

2. What is WISP ?
It is fixed wireless service between the central node and the client
direct line of sight required
low power radios and high gain antennas are used
It IS NOT a mobile service.
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).
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MikroTik WISP

3. RF Information Broadband Technology Spread Spectrum Technology
Direct Sequence Spread Spectrum (DSSS)
Frequency Hopping Spread Spectrum (FHSS)
Frequencies for Unlicensed SS
MHz ISM band, or
MHz ISM band
Narrowband Technology A narrowband radio system transmits and receives user information on a specific radio frequency. Narrowband radio keeps the radio signal frequency as narrow as possible just to pass the information. Undesirable crosstalk between communications channels is avoided by carefully coordinating different users on different channel frequencies.
Spread Spectrum Technology Most wireless LAN systems use spread-spectrum technology, a wideband radio frequency technique developed by the military for use in reliable, secure, mission-critical communications systems. Spread-spectrum is designed to trade off bandwidth efficiency for reliability, integrity, and security. In other words, more bandwidth is consumed than in the case of narrowband transmission, but the tradeoff produces a signal that is, in effect, louder and thus easier to detect, provided that the receiver knows the parameters of the spread-spectrum signal being broadcast. If a receiver is not tuned to the right frequency, a spread-spectrum signal looks like background noise. There are two types of spread spectrum radio: frequency hopping and direct sequence.
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MikroTik WISP

4. DS versus FH Direct Sequence Frequency Hopping
(+) Faster (up to 11 Mbps) and Greater Range
(+) recently standardization has made this the lowest cost radio
Frequency Hopping
(-) higher cost per radio
(-) Slower (max 3 Mbps) and Limited Range
Frequency-Hopping Spread Spectrum Technology Frequency-hopping spread-spectrum (FHSS) uses a narrowband carrier that changes frequency in a pattern known to both transmitter and receiver. Properly synchronized, the net effect is to maintain a single logical channel. To an unintended receiver, FHSS appears to be short-duration impulse noise.
Direct-Sequence Spread Spectrum Technology Direct-sequence spread-spectrum (DSSS) generates a redundant bit pattern for each bit to be transmitted. This bit pattern is called a chip (or chipping code). The longer the chip, the greater the probability that the original data can be recovered (and, of course, the more bandwidth required). Even if one or more bits in the chip are damaged during transmission, statistical techniques embedded in the radio can recover the original data without the need for retransmission. To an unintended receiver, DSSS appears as low-power wideband noise and is rejected (ignored) by most narrowband receivers.
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MikroTik WISP

5. 2.4GHz Spread Spectrum Channels Interference
1 to 13 depending on the set
three non-overlapping ones
Interference
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MikroTik WISP

6. Antenna Types Directional Sectorial Omnidirectional Parabolic
Yagi or Loop Yagi
Sectorial
Horns
Omnidirectional
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MikroTik WISP

7. Antenna Polarity Omnidirectional and Sectorial Antennas
Vertical E-Plane
Directional Antennas
Vertical or Horizontal E-Plane depending on the mounting of antenna
For communicating radios the antennas should match the polarity
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MikroTik WISP

8. Mounting of Antennas Polarity Vertical and Horizontal Alignment Safety
Lightning Strikes
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MikroTik WISP

9. Cabling Requirements High Quality Cables
Low Loss - LMR-400 / Belden 99xx
Super Low Loss - LMR-600
Cable Length - as short as possible
Recommended 3-5m for omni antennas
~10m for directional antennas, depending on the distances, antenna gains, and radio power
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MikroTik WISP

10. Cable Connectors Standard Proprietary
N Connectors (male or female) for antennas
Proprietary
RP-TNC Connectors for Aironet Radio
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MikroTik WISP

11. Using Antenna Calculator
Distances to be covered
Cabling Length
Antenna Gains
Radio
Power
Receive Sensitivity
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MikroTik WISP

12. WISP Topologies Point to point links Point to multipoint links
(+) longer distances (max 30-40km)
(-) higher cost/client
Point to multipoint links
(+) serving multiple clients at lower cost/client
(+) larger area of coverage
(-) lower range (max 5-12km)
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MikroTik WISP

13. What can be connected? Internet Connectivity Client’s LAN to the ISP
Client LAN uses a Wireless Gateway Router which connects to the Base Station of the ISP
Client's Computer to the ISP
Client’s Computer with a Wireless NIC connects to the Base Station of the ISP
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MikroTik WISP

14. What can be connected? Intranet Connectivity
Client’s LAN1 to Client’s LAN2
Client’s LAN at a remote location uses a Wireless Router which connects to the Wireless Router at the main office
Client's Computer to the Client’s LAN
Client’s Computer at a remote location connects to the Wireless Router at the main office
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MikroTik WISP

15. Wireless Setup Diagrams
Used conventions
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MikroTik WISP

16. Base Setup
All customers are using the same 11Mb/s channel. This configuration can be used for unlimited number of clients. The link between the Base Site and the clients is 11 Mb/s.
If additional Ethernet NIC is installed in the wireless router located in a building, then more than one client network can be connected to the wireless router.
Each of the client networks are separated from each other since they are connected to different interfaces of the router.
The bandwidth management can be done at at the Ethernet/Ethernet router located at the ISP.
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MikroTik WISP

17. Repeater Setup
All customers are using the same 11Mb/s channel. The Internet Service Provider is also using this channel. This means that there is no "backbone" to the Base Unit. This configuration can be used for five to ten LANs from 5 to 50 computers each. The link between the Repeater Site and the clients is Mb/s.
It is possible to connect one more MikroTik router (so one more LAN) to the Base Unit on the building using Ethernet Cable. The link between the ISP and the client located at the repeater site is 11 Mb/s.
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MikroTik WISP

18. Advanced Repeater Setup
All customers are using the same 11Mb/s channel. The Internet Service Provider is also using this channel. This means that there is no "backbone" to the Base Unit. This configuration can be used for five to ten LANs from 5 to 50 computers each. The link between the ISP and the wireless clients is Mb/s.
It is possible to connect one more MikroTik router (so one more LAN) to the Base Unit on the building using Ethernet Cable. The link between the ISP and the client located at the repeater site is 11 Mb/s.
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MikroTik WISP

19. Base Setup with Backbone
Base Unit has 11Mb/s channel. Internet Service Provider has a separate backbone link going to the Base Unit. All customers are using the same 11Mb/s channel. This configuration can be used for unlimited number of clients. The link between the Base Site and the clients is 11 Mb/s.
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MikroTik WISP

20. Point-to-Point Setup
You can connect two Local Area Networks using two MikroTik routers and point-to-point link. So there will be 11 Mb/s channel between two LANs. This configuration is used in the Backbone Setup. There is a point-to-point link between the ISP and the Base Site.
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MikroTik WISP

21. IP Questionnaire Type of cable used What IP addresses are used
10 Base 2, 10 Base T, 10/100 Mbps?
If fiber optic - get a transceiver to 10BaseT…
What IP addresses are used
what network, network mask? Get one address for the router as the gateway for the LAN.
No addresses used yet.
Assign a private network, e.g., ….
Use addresses given by the ISP
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MikroTik WISP

22. RF Network Configuration
System Identificator
Should be unique
Channel / Frequency
Should have minimal interference with other systems
Data Rates
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MikroTik WISP

23. Base Unit Configuration
Connect the Antenna
Connect the Ethernet Cable
Connect the RS-232 Console Cable
Use Terminal Emulation Program on your Laptop or Desktop PC
Connect the Power Supply
Power the unit on
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MikroTik WISP

24. Basic Configuration Configure RF Parameters
System Identifier
Frequency
Data Rates
Configure the Identification Parameters
Name
IP Address / Mask / Default Gateway
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MikroTik WISP

25. Things to Remember Association Restriction Passwords for the Unit
Maintain a list of controlled nodes
Turn Autoregistration off
Passwords for the Unit
Write - View and Change the Configuration, perform Diagnostics
Read - View Configuration
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MikroTik WISP

26. IP Network Configuration
Global Addresses
use routing configuration
Local Addresses, no server
use masquerading
Local Addresses, local server
use masquerading and NAT
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MikroTik WISP

27. System Diagnostics Check the RF Communication
Registration/Association
Signal Strength and Quality
Link Speed
Check the IP Configuration
Network Address/Mask
Routing, Default Gateway
Ping, Traceroute
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MikroTik WISP