User Manual

802.11a/b/g Combo Mini PCI WLAN Card User’s Manual
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Roaming Between Multiple Access Points
For large environments, multiple Access Points can be implemented to extend the wireless service coverage area for seamless wireless access. It allows
wireless clients to roam from one AP to another while maintaining the wireless connectivity at all times. A wireless client wandering across multiple
APs will automatically change the operating radio frequency as required.
In a roaming network, all APs and wireless clients must have the same Service Set Identity (SSID) and security setting (if enabled). Alternatively the
mobile station may use an SSID of “any” to associate with any available AP, regardless of the AP’s SSID. Roaming among different Access Points is
controlled automatically to maintain the wireless connectivity at all times.
Figure 1-3 Roaming Across Multiple Access Points
802.11a, 802.11b and 802.11g
As this Wireless LAN Card is an IEEE 802.11a/b/g combo radio solution, you can connect to either an 802.11a, 802.11b or 802.11g network. Getting
familiar of some distinguish differences between these two standards will help you better understand your device.
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Operating Frequency Band
802.11b and 802.11g operate in the 2.4GHz band while 802.11a operates in the 5GHz band. Therefore, throughout this manual the 2.4 GHz-
related terms are referred to 802.11b/g networks while 5 GHz is referred to 802.11a.
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Data Rates
802.11b supports data rates of 1, 2, 5.5, and 11 Mbps.
802.11g supports data rates of 1, 2, 5.5, 6, 9,11, 12, 18, 24, 36, 48 and 54Mbps.
802.11a supports mandatory data rates of 6, 12, and 24 Mbps and optional data rates of 9, 18, 36, and 54 Mbps.
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Modulation
802.11a employs Orthogonal Frequency Division Modulation (OFDM) scheme. 802.11b uses Direct Sequence Spread Spectrum (DSSS)
technologies. 802.11g uses Complementary Code Keying (CCK) and Orthogonal Frequency Division Modulation (OFDM).