NETGEAR CG814WG V2, Справочное руководство

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Reference Manual for the Wireless Cable Modem Gateway CG814WG v2
Networks, Routing, and Firewall Basics B-15
If the decrypted text does not match the original challenge text (i.e., the access point and station do
not share the same WEP Key), then the access point will refuse to authenticate the station and the
station will be unable to communicate with either the 802.11b network or Ethernet network.
This process is illustrated in below.
Figure B-5: 802.11b shared key authentication
Overview of WEP Parameters
Before enabling WEP on an 802.11b network, you must first consider what type of encryption you
require and the key size you want to use. Typically, there are three WEP Encryption options
available for 802.11b products:
1.
Do Not Use WEP: The 802.11b network does not encrypt data. For authentication purposes,
the network uses Open System Authentication.
2.
Use WEP for Encryption: A transmitting 802.11b device encrypts the data portion of every
packet it sends using a configured WEP Key. The receiving 802.11b device decrypts the data
using the same WEP Key. For authentication purposes, the 802.11b network uses Open
System Authentication.
3.
Use WEP for Authentication and Encryption: A transmitting 802.11b device encrypts the
data portion of every packet it sends using a configured WEP Key. The receiving 802.11b
device decrypts the data using the same WEP Key. For authentication purposes, the 802.11b
network uses Shared Key Authentication.
I N TER N ET LO C A L
ACT
1 2 3 4 5 6 7 8
LNK
LNK/ACT
100 Cable/DSL ProSafe Wireless VPN Security Firewall
MODEL FVM318
PWR TEST
W LA N
Enable
Access Point
1) Authentication
request sent to AP
2) AP sends challenge text
3) Client encrypts
challenge text and
sends it back to AP
4) AP decrypts, and if correct,
authenticates client
5) Client connects to network
802.11b Authentication
Shared Key Steps
Cable or
DLS modem
Client
attempting
to connect