Verint Nextiva S4200-2V-BZ, Руководство пользователя

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2: System and RF Planning
16 Verint Video Intelligence Solutions
In Europe, the 11 independent channels, for indoor or outdoor use, are:
Wireless Cells
A wireless network is designed such that information can travel back and forth between two
points without the need for wires. For the S4200, this information consists of digitized
video, audio, and PTZ data sent to and from the wired network via an outdoor wireless
access point—either the Nextiva S4300 device or a commercial 802.11 access point.
A wireless cell consists of a group of wireless devices that communicate together on the
same frequency channel and that share the same wireless passkey. For example:
You can colocate many wireless cells if you respect certain conditions (see page 31).
Devices in a wireless cell can have two MAC (Media Access Control) roles, master or slave:
„
A master device controls the access over the wireless medium. It takes care of channel
selection and slave authentication to provide access to the wireless network. Finally, the
master allocates bandwidth among all connected slaves.
„
Slave devices need a master to access the wireless medium to transfer data, through a
polling mechanism. The S4200 devices are always slaves.
Channel Frequency (GHz) Channel Frequency (GHz)
100 5.50 124 5.62
104 5.52 128 5.64
108 5.54 132 5.66
112 5.56 136 5.68
116 5.58 140 5.70
120 5.60
S4300
S4200