ZyXEL Communications G-4100 V2 User Manual page 181

Table 45 ADVANCED > WIRELESS (continued)
LABEL
WEP Key 1 ... 4 Enter the WEP keys in the fields provided and select a key as the default key to use.
Beacon Interval Set the number of milliseconds that should pass between sending out a beacon.
RTS Threshold
Fragmentation
Threshold
Preamble Type
Authentication
Method
Chapter 23 Wireless LAN
DESCRIPTION
If you select 64 bit in the WEP Encryption field.
Enter either 10 hexadecimal digits in the range of "A-F", "a-f" and "0-9" (for example
11AA22BB33) for HEX key type
or
Enter 5 printable ASCII characters (case sensitive) ranging from "a-z", "A-Z" and "0-
9" (for example MyKey) for ASCII key type.
If you select 128 bit in the WEP Encryption field,
Enter either 26 hexadecimal digits in the range of "A-F", "a-f" and "0-9" (for example,
00112233445566778899AABBCC) for HEX key type
or
Enter 13 printable ASCII characters (case sensitive) ranging from "a-z", "A-Z" and "0-
9" (for example, MyKey12345678) for ASCII key type.
Note: The values for the WEP keys must be set up exactly the same
on all wireless devices in the same wireless LAN.
ASCII WEP keys are case sensitive.
Enter a time period between 1 and 1000. The default is 100.
Enter a value between 0 and 2442 to enable an RTS/CTS handshake to avoid
retransmitting due to hidden nodes. The default is 2432.
Enter a value between 256 and 2446 to enable a fragmentation threshold. This sets
the maximum size of data fragments that can be sent. The default is 2432. Use a low
setting if there is a great deal of radio interference.
Preamble is used to signal that data is coming to the receiver.
Short preamble increases performance as less time sending preamble means more
time for sending data. All IEEE 802.11b compliant wireless adapters support long
preamble, but not all support short preamble.
Select Long Preamble if you are unsure what preamble mode the wireless adapters
support, and to provide more reliable communications in busy wireless networks.
Select Short Preamble if you are sure the wireless adapters support it, and to
provide more efficient communications.
Select Open System to allow any device to authenticate and then attempt to
communicate with the ZyXEL Device. Using open authentication, any wireless device
can authenticate with the ZyXEL Device, but the device can only communicate if its
WEP keys match the ZyXEL Device. Devices not using WEP do not attempt to
authenticate with a ZyXEL Device that is using WEP. Open authentication does not
rely on a RADIUS server on your network.
Select Shared Key to have the ZyXEL Device use shared key authentication. The
ZyXEL Device sends an unencrypted challenge text string to any device attempting
to communicate with the ZyXEL Device. The device-requesting authentication
encrypts the challenge text and sends it back to the ZyXEL Device. If the challenge
text is encrypted correctly, the ZyXEL Device allows the requesting device to
authenticate. However, both the unencrypted challenge and the encrypted challenge
can be monitored; thus leaving the ZyXEL Device open to attack from an intruder
who calculates the WEP key by comparing the unencrypted and encrypted text
strings. Because of this weakness, shared key authentication can be less secure
than open authentication. Like open authentication, shared key authentication does
not rely on a RADIUS server on your network.
Select Both to allow subscribers to communicate with or without data encryption.
G-4100 v2 User's Guide
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