ZyXEL VMG4927-B50A User Guide - Page 297

Appendix B Wireless LANs If the Fragmentation Threshold value is smaller than the RTS/CTS value (see previously) you set then the RTS (Request To Send)/CTS (Clear to Send) handshake will never occur as data frames will be fragmented before they reach RTS/CTS size. IEEE 802.11g Wireless LAN IEEE 802.11g is fully compatible with the IEEE 802.11b standard. This means an IEEE 802.11b adapter can interface directly with an IEEE 802.11g access point (and vice versa) at 11 Mbps or lower depending on range. IEEE 802.11g has several intermediate rate steps between the maximum and minimum data rates. The IEEE 802.11g data rate and modulation are as follows: Table 135 IEEE 802.11g DATA RATE (MBPS) MODULATION 1 DBPSK (Differential Binary Phase Shift Keyed) 2 DQPSK (Differential Quadrature Phase Shift Keying) 5.5 / 11 CCK (Complementary Code Keying) 6/9/12/18/24/36/48/54 OFDM (Orthogonal Frequency Division Multiplexing) Wireless Security Overview Wireless security is vital to your network to protect wireless communication between wireless clients, access points and the wired network. Wireless security methods available on the VMG are data encryption, wireless client authentication, restricting access by device MAC address and hiding the VMG identity. The following figure shows the relative effectiveness of these wireless security methods available on your VMG. Table 136 Wireless Security Levels SECURITY LEVEL SECURITY TYPE Least Secure Unique SSID (Default) Unique SSID with Hide SSID Enabled Most Secure MAC Address Filtering Note: You must enable the same wireless security settings on the VMG and on all wireless clients that you want to associate with it. RADIUS RADIUS is based on a client-server model that supports authentication, authorization and accounting. The access point is the client and the server is the RADIUS server. The RADIUS server handles the following tasks: • Authentication Determines the identity of the users. VMG4927-B50A / VMG9827-B50A User's Guide 297