Raspberry Pi A, Руководство пользователя, Страница: 103 / 314

C H A P T E R 5
N E T W O R K C O N F I G U R A T I O N
87
❍
Standard
—The IEEE 802.11 wireless standards have a variety of different types, dis-
tinguished by a letter suffix. This section lists the standards supported by the USB
wireless adapter. For the example adapter, this reads
IEEE 802.11bgn
for the net-
work types it can address.
❍
ESSID —The SSID of the network to which the adapter is connected. If the adapter is
not currently connected to a network, this will read
off/any
.
❍
Mode
—The mode that the adapter is currently operating in, which will be one of the
following:
•
Managed —A standard wireless network, with clients connecting to access
points. This is the mode used for almost all home and business networks.
•
Ad-Hoc
—A device-to-device wireless network, with no access points.
•
Monitor
—A special mode in which the card listens out for all traffic whether or
not it is the addressee. This mode is typically used in network troubleshooting for
capturing wireless network traffic.
•
Repeater
—A special mode that forces a wireless card to forward traffic on to
other network clients, to boost signal strength.
•
Secondary —A subset of the Repeater mode, which forces the wireless card to act
as a backup repeater.
❍
Access Point
—The address of the access point to which the wireless adapter is cur-
rently connected. If the adapter isn’t connected to a wireless access point, this will read
Not-Associated
.
❍
Tx-Power—
The transmission power of the wireless adapter. The number displayed
here indicates the strength of the signal that the adapter is sending: the higher the
number, the stronger the signal.
❍
Retry—
The current setting for the wireless adapter’s transmission retry, used on con-
gested networks. This does not normally need changing, and some cards won’t allow it
to be changed.
❍
RTS
—The adapter’s current setting for Ready To Send and Clear To Send (RTS/CTS)
handshaking, used on busy networks to prevent collisions. This is normally set by the
access point on connection.
❍
Fragment
—The maximum fragment size, used on busy networks to split packets up
into multiple fragments. This is normally set by the access point on connection.
❍
Power Management —The current status of the adapter’s power management function-
ality, which reduces the device’s power demands when the wireless network is idle. This has
little effect on the Pi, but is typically enabled for battery-powered devices like a laptop.