12
Other related procedures
1.
De-authentication
A de-authentication frame can be sent by either an AP or wireless client to break an existing link. In a wireless
system, de-authentication can occur due to many reasons, such as:
Receiving an association/disassociation frame from a client which is unauthenticated.
Receiving a data frame from a client which is unauthenticated.
Receiving a PS-poll frame from a client which is unauthenticated.
2.
Dissociation
A dissociation frame can be sent by an AP or a wireless client to break the current wireless link. In the wireless
system, dissociation can occur due to many reasons, such as:
Receiving a data frame from a client which is authenticated and unassociated.
Receiving a PS-Poll frame from a client which is authenticated and unassociated.
WLAN topologies
WLAN topologies for fat APs consist of:
Single BSS
Multi-ESS
Single ESS Multi-BSS
Single BSS
The coverage of an AP is a BSS. Each BSS is identified by a BSSID. The most basic WLAN network can be
established with only one BSS. All wireless clients associate with the same BSS. If these clients have the same
authorization, they can communicate with each other.
Figure 5
shows a single BSS network.
Figure 5
Single BSS network
The clients can communicate with each other or reach a host in the Internet. Communications between clients
within the same BSS are carried out through the fat AP.
FAT AP
Gateway
Client1
Client 2
BSS
Internet
Содержание a-msr
Страница 48: ...44 Figure 19 Configure the wireless card I ...
Страница 49: ...45 Figure 20 Configure the wireless card II ...