3Com Corporation WL306 Manuel D’Utilisation

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them. After successful authentication, the TLS server securely sends the session 
keys to the access point and user data is allowed to pass. EAP-TLS is currently 
supported only under Windows XP.
3Com Serial
Authentication
Serial Authentication, a 3Com-proprietary upper layer authentication mechanism, 
uses a two-phase process involving both EAP-TLS and EAP-MD5
In the first phase, the wireless client and the RADIUS EAP-TLS server mutually 
authenticate each other. All clients can authenticate to the TLS server because 
a common certificate is provided during software installation. Successful 
completion of this phase establishes dynamic session keys that protect 
subsequent communication between the wireless client and access point.
In the second phase, the server can securely use EAP-MD5 to authenticate the 
user. Once authenticated, the server informs the access point and data traffic 
from the client is allowed to pass to the wired network.
3Com Serial Authentication also includes optional dynamic session-key renewal, 
which greatly enhances system security. Dynamic key renewal means that, 
following the initial upper layer authentication, the client and the access point 
periodically update the session keys used for encryption. 
3Com’s Serial Authentication method provides obvious advantages. By combining 
encryption key distribution and a secure network authentication, it makes use of 
two complementary authentication schemes. Additionally, the client and the 
access point dynamically update session keys while the network session is in 
progress. Because Serial Authentication is a 3Com proprietary scheme, it must be 
used with the 3Com Wireless LAN PC Card (model 3CRWE62092A) and the 3Com 
Access Point 8000. Serial authentication is supported by the 3Com 802.1x agent 
(described below).
Additional Security 
Configuration Options
If you choose not to use an upper layer authentication scheme, 3Com’s security 
solution also supports the authentication and encryption methods described 
below.
Open Network. The open-network option assumes that neither authentication 
nor encryption are required. No security is used.
40-bit Shared Key Encryption. This option is compatible with Wi-Fi certified 
equipment from other vendors. Encryption keys must be set up on both the client 
and the access point. The network administrator sets up a fixed set of encryption 
keys for the wireless network and supplies users with an encryption string or a set 
of hexadecimal keys. This option can be used with local access point 
authentication or with EAP-MD5 RADIUS authentication.
128-bit Shared Key Encryption. This option is compatible with 128-bit shared 
key from most vendors, including 3Com, Agere, and Cisco. The network 
administrator sets up encryption keys for the wireless network and supplies users 
with an encryption string or hexadecimal keys. You must set up encryption keys on 
both the client and access point. This option can be used with local access point 
authentication or with EAP-MD5 RADIUS authentication.