Denon AVP-A1HD Owner's Manual page 102

WPA (Wi-Fi Protected Access)
This is a security standard established by the Wi-Fi Alliance. In addition
to the conventional SSID (network name) and WEP key (network key),
it also uses a user identification function and encrypting protocol for
stronger security.
WPA2 (Wi-Fi Protected Access 2)
This is a new version of the WPA established by the Wi-Fi Alliance,
compatible with more secure AES encryption.
WPA-PSK/WPA2-PSK (Pre-shared Key)
This is a simple authentication system for mutual authentication when
a preset character string matches on the wireless LAN access point
and client.
Passphrase
This refers to the code key used for WPA-PSK/WPA2-PSK authentication,
a WPA authentication method.
TKIP (Temporal Key Integrity Protocol)
This is a network key used for WPA. The encryption algorithm is RC4,
the same as for WEP, but the security level is increased by changing
the network key used for encryption for each packet.
AES (Advanced Encryption Standard)
This is a next generation standard encryption method replacing the
current DES and 3DES, and because of its high security it is expected
to be applied widely to wireless LANs in the future. It uses the
"Rijndael" algorithm developed by two Belgian cryptographers to
divide the data into blocks of fixed lengths and encrypt each block. It
supports data lengths of 128, 192 and 256 bits and key lengths of 128,
192 and 256 bits as well, offering extremely high encryption security.