Sony VAIO VGN-TXN10 Series, Руководство пользователя

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Using Your VAIO Computer
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In some countries, using WLAN products may be restricted by the local regulations (e.g. limited number of channels). Therefore, before activating the
WLAN functionality, read the Safety Information carefully.
WLAN uses the IEEE 802.11a
*
/b/g standard, which specifies the used technology. The standard includes the encryption methods: Wired Equivalent
Privacy (WEP), which is a security protocol, Wi-Fi Protected Access 2 (WPA2), and Wi-Fi Protected Access (WPA). Proposed jointly by the IEEE and
Wi-Fi Alliance, both WPA2 and WPA are specifications of standards based, interoperable security enhancements that increase the level of data
protection and access control for existing Wi-Fi networks. WPA has been designed to be forward compatible with the IEEE 802.11i specification. It
utilizes the enhanced data encryption TKIP (Temporal Key Integrity Protocol) in addition to user authentication using 802.1X and EAP (Extensible
Authentication Protocol). Data encryption protects the vulnerable wireless link between clients and access points. Besides that, there are other typical
LAN security mechanisms to ensure privacy, such as: password protection, end-to-end encryption, virtual private networks, and authentication. WPA2,
the second generation of WPA, provides stronger data protection and network access control and is also designed to secure all versions of 802.11
devices, including 802.11b, 802.11a, and 802.11g, multi-band and multi-mode. In addition, based on the ratified IEEE 802.11i standard, WPA2 provides
government grade security by implementing the National Institute of Standards and Technology (NIST) FIPS 140-2 compliant AES encryption algorithm
and 802.1X-based authentication. WPA2 is backward compatible with WPA.
* See the online Specifications to see whether your model supports the IEEE 802.11a standard.
Wireless LAN devices using the IEEE 802.11a standard and the ones using the IEEE 802.11b or g standard cannot communicate because the frequencies
are different.
IEEE 802.11b: The standard speed is 11 Mbps, or about 30 to 100 times faster than a standard dial up.
IEEE 802.11a/g: The standard speed is 54 Mbps, or about 5 times faster than a Wireless LAN device using the IEEE 802.11b standard.
The 2.4 GHz bandwidth used by wireless LAN compatible devices is also used by other various devices. Although technologies to minimize interference
from other devices that use the same bandwidth are employed on wireless LAN compatible devices, such interference may cause lower communication
speed, narrower communication range, or broken wireless connections.
The communication speed varies depending on the distance between communication devices, existence of obstacles between such devices, the device
configuration, the radio conditions, and the software in use. In addition, communications may be cut off depending on the radio conditions.