Cisco Cisco IP Phone 8841 Designanleitung
Cisco IP Phone 8861 and 8865 Wireless LAN Deployment Guide
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Occurs when multipath is so severe that the receiver is unable to detect the transmitted information.
Signal Nulling
Occurs when the reflected waves arrive exactly out of phase with the main signal and cancel the main signal
completely.
Occurs when the reflected waves arrive exactly out of phase with the main signal and cancel the main signal
completely.
Increased Signal Amplitude
Occurs when the reflected waves arrive in phase with the main signal and add on to the main signal thereby increasing
the signal strength.
Occurs when the reflected waves arrive in phase with the main signal and add on to the main signal thereby increasing
the signal strength.
Decreased Signal Amplitude
Occurs when the reflected waves arrive out of phase to some extent with the main signal thereby reducing the signal
amplitude.
Occurs when the reflected waves arrive out of phase to some extent with the main signal thereby reducing the signal
amplitude.
Use of
Orthogonal Frequency Division Multiplexing (OFDM)
, which is used by 802.11a/n/ac and 802.11g/n, can help to reduce
issues seen in high multipath environments.
If using 802.11b in a high multipath environment, lower data rates should be used in those areas (e.g. 1 and 2 Mbps).
Use of antenna diversity can also help in such environments.
If using 802.11b in a high multipath environment, lower data rates should be used in those areas (e.g. 1 and 2 Mbps).
Use of antenna diversity can also help in such environments.
Security
When deploying a wireless LAN, security is essential.
The Cisco IP Phone 8861 and 8865 support the following wireless security features.
The Cisco IP Phone 8861 and 8865 support the following wireless security features.
WLAN Authentication
• WPA2 (802.1x authentication + AES or TKIP encryption)
• WPA (802.1x authentication + TKIP or AES encryption)
• WPA2-PSK (Pre-Shared key + AES encryption)
• WPA-PSK (Pre-Shared key + TKIP encryption)
• EAP-FAST (Extensible Authentication Protocol - Flexible Authentication via Secure Tunneling)
• EAP-TLS (Extensible Authentication Protocol - Transport Layer Security)
• PEAP-GTC (Protected Extensible Authentication Protocol - Generic Token Card)