ZyWALL 5/35/70 Series User’s Guide
In a network environment with multiple access points, wireless stations are able to switch from one access point to another as they move between the coverage areas. This is roaming. As the wireless station moves from place to place, it is responsible for choosing the most appropriate access point depending on the signal strength, network utilization or other factors.
The roaming feature on the access points allows the access points to relay information about the wireless stations to each other. When a wireless station moves from a coverage area to another, it scans and uses the channel of a new access point, which then informs the access points on the LAN about the change. The new information is then propagated to the other access points on the LAN. An example is shown in Figure 451.
If the roaming feature is not enabled on the access points, information is not communicated between the access points when a wireless station moves between coverage areas. The wireless station may not be able to communicate with other wireless stations on the network and vice versa.
Figure 451 Roaming Example
The steps below describe the roaming process.
1As wireless station Y moves from the coverage area of access point P1 to that of access point
2P2, it scans and uses the signal of access point P2.
3Access point P2 acknowledges the presence of wireless station Y and relays this information to access point P1 through the wired LAN.
4Access point P1 updates the new position of wireless station.
5Wireless station Y sends a request to access point P2 for
Appendix H Wireless LANs | 716 |