This section provides a quick reference to wireless networking and Planner related terms and abbreviations used in this guide.
Table 3 Glossary of Terms802.11
AP
BoM
Channel Interference
Layout Model
Layout Image
RF Calculation Cell Size
802 Series LANs
Access Point
Bill of Material
The model of the Layout with all the object placements defined
A .jpg, .gif image file of the Layout
Granularity of the RF computations of the WLAN signal strength
Description
The IEEE 802.11 is a standard for WLANs. This standard is continuously developed to provide better and higher transmission rates.
An AP is an interface between wireless and wired networks. It connects wireless Clients with an Ethernet to extend their range.
Bill of Material is a detailed report that contains network inventory along with the placement of APs and Sensors throughout the site. It displays a list of APs and Sensors on each layout, their configuration, the Vendor/Model Number, the protocol used and its distance from the NorthWest corner.
Channels are important to understand because they affect the overall capacity of the Wireless LAN. A channel represents a narrow band of radio frequency. A radio frequency modulates within a band of frequencies; as a result of which there is a limited amount of bandwidth within any given range to carry data. It is important that the frequencies do not overlap or else the throughput would be significantly lowered as the network sorts and reassembles the data packets sent over the air.
The 802.11b specification operates at radio frequencies in the 2.4 to 2.497 GHz range and supports overlapping channels of 22 MHz each. The frequency ranges and channels vary based on the regulatory standards adopted by a country. For instance, in the US, the FCC standard allows up to 11 channels whereas in Europe the ETSI standard allows up to 13 channels.
When there are more than one source transmitting on a radio frequency simultaneously, the receiver sees more than its partner source. The receiver will have difficulties distinguishing one from the other and the data will be lost. This is interference. Channels you chose for the Clients and APs are susceptible to interference. Therefore, it is important to ensure you are on the correct frequency by selecting appropriate channels for the APs.
After you import the layout image into Planner, the Layout Designer helps designing the Layout Model. The Layout Model is a ready layout of the entire layout for which you are performing WLAN planning. The Layout Model contains all the objects, locations of walls, windows, and doors with the details of the materials used in it.
In the context of Planner, a Layout Image serves as the primary input to the entire planning process.
When you create a new plan, Planner determines the granularity of the RF computations of the WLAN signal strength distribution throughout the plan. It divides the plan into small units and then calculates the RF characteristics for each unit. The
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3Com ® AirProtect Planner User Guide