Sony PCWA-A220 - Manual (Page 55)

Encryption Key (WEP Key)
Systems exist w ith the capability to retrieve IDs from this Wireless Access Point and similar products made by other companies.
If you leave the Encryption Key (WEP Key) at the factory setting, individuals near the customer w ho has such a system can easily obtain the customer's
Encryption Key from the Access Point ID. This w ould allow them to maliciously use the customer's Access Point to access the Internet through their account. From
a security standpoint, w e strongly recommend changing the Encryption Key.
Note
Make sure to remember Encryption Key changes made by the customer.
You can use the Custom Access Point Setup Utility to set the Access Point to be a closed system. Thereby clients on Wireless LAN connected to another Access
Point other than that Access Point cannot view it under normal operations.
(This function does not completely conform to IEEE802.11.)
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