Federal Communications Commission. See www.fcc.gov for more information.


A firewall is a blocking mechanism—either hardware, software, or both—that blocks intruders from accessing a network or individual computer.

free radio spectrum

Bands of the radio spectrum, such as 2.4GHz and 5GHz, that do not require a license from the FCC. Wi-Fi uses these bands for its transmissions, as do other household appliances such as cordless phones and microwaves.


The oscillations, or movement from peak to trough, of the electromagnetic wave created by a radio transmission.

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