Cisco 7920 Administration Guide - Page 49

Choosing Authentication and Encryption Methods - setup

Page 49 highlights

Chapter 2 An Overview of the Wireless Network Components of the VoIP Wireless Network • WEP -When using WEP in the wireless network, authentication happens at the access point by using open or shared-key authentication. The WEP key that is setup on the phone must match with the WEP key that is configured at the access point for successful connections. The Cisco Wireless IP Phone 7920 supports WEP keys that use 40-bit encryption or a 128-bit encryption and remain static on the phone and access point. LEAP and CCKM authentication can use WEP keys for encryption. The RADIUS server manages the WEP key and passes a unique key to the access point after authentication for encrypting all voice packets; consequently, these WEP keys can change with each authentication. • Temporal Key Integrity Protocol (TKIP)-WPA and CCKM use TKIP encryption that has several improvements over WEP. TKIP provides per-packet key ciphering and longer initialization vectors (IVs) that strengthen encryption. In addition, a message integrity check (MIC) ensures that encrypted packets are not being altered. TKIP removes the predictability of WEP that helps intruders decipher the WEP key. Note The Cisco Wireless IP Phone 7920 does not support Cisco Key Integrity Protocol (CKIP) with CMIC or Advanced Encryption Standard (AES) encryption. Choosing Authentication and Encryption Methods Authentication and encryption schemes are setup within the wireless LAN. VLANS are configured in the network and on the access points and specify different combinations of authentication and encryption. An SSID is associated with a VLAN and its particular authentication and encryption scheme. In order for wireless client devices to authenticate successfully, you must configure the same SSIDs with their authentication and encryption scheme requirements on the access points and on the wireless client devices, such as the Cisco Wireless IP Phone. Some authentication schemes require specific types of encryption. With Open authentication, you have the option to use static WEP for encryption and added security. But if you are using Shared Key authentication, you must set static WEP for encryption, and you must configure the WEP key on the phone. OL-7104-01 Cisco Wireless IP Phone 7920 Administration Guide for Cisco CallManager Release 4.0 and 4.1 2-15

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2-15
Cisco Wireless IP Phone 7920 Administration Guide for Cisco CallManager Release 4.0 and 4.1
OL-7104-01
Chapter 2
An Overview of the Wireless Network
Components of the VoIP Wireless Network
WEP —When using WEP in the wireless network, authentication happens at
the access point by using open or shared-key authentication. The WEP key
that is setup on the phone must match with the WEP key that is configured at
the access point for successful connections. The Cisco Wireless
IP Phone 7920 supports WEP keys that use 40-bit encryption or a 128-bit
encryption and remain static on the phone and access point.
LEAP and CCKM authentication can use WEP keys for encryption. The
RADIUS server manages the WEP key and passes a unique key to the access
point after authentication for encrypting all voice packets; consequently,
these WEP keys can change with each authentication.
Temporal Key Integrity Protocol (TKIP)—WPA and CCKM use TKIP
encryption that has several improvements over WEP. TKIP provides
per-packet key ciphering and longer initialization vectors (IVs) that
strengthen encryption. In addition, a message integrity check (MIC) ensures
that encrypted packets are not being altered. TKIP removes the predictability
of WEP that helps intruders decipher the WEP key.
Note
The Cisco Wireless IP Phone 7920 does not support Cisco Key Integrity
Protocol (CKIP) with CMIC or Advanced Encryption Standard (AES)
encryption.
Choosing Authentication and Encryption Methods
Authentication and encryption schemes are setup within the wireless LAN.
VLANS are configured in the network and on the access points and specify
different combinations of authentication and encryption. An SSID is associated
with a VLAN and its particular authentication and encryption scheme. In order for
wireless client devices to authenticate successfully, you must configure the same
SSIDs with their authentication and encryption scheme requirements on the
access points and on the wireless client devices, such as the Cisco Wireless
IP Phone.
Some authentication schemes require specific types of encryption. With Open
authentication, you have the option to use static WEP for encryption and added
security. But if you are using Shared Key authentication, you must set static WEP
for encryption, and you must configure the WEP key on the phone.