If the Encryption option set to On , then all transmitted data packets are encrypted and any unencrypted received packets are discarded. The Encryption option may be set to Mixed . In this mode a root or repeater bridge accepts association from clients with encryption turned On or Off . In this case, only data packets between nodes that both support are encrypted. Multi-cast packets are sent in the clear.
All nodes can see the packets.
The Mixed mode is not recommend. If a client with encryption enabled sends a multicast packet to its parent, the packet is encrypted. Viewing a packet in both encrypted and unencrypted form, can contribute to breaking a key. This mode is only included for compatibility with other vendors. Two main steps are required to set up WEP on the Cisco Aironet Client Adapter.