Cisco Cisco Aironet 350 Wireless Bridge Guía Para Resolver Problemas
Methods You Can Use to Extend the Radio Coverage Area
of the WLAN
of the WLAN
The radio coverage area that a single AP provides is not sufficient to serve the entire WLAN in many
situations. The solution is to increase the radio coverage area. There are different options available that you
can use to increase the radio coverage area. These sections explain each of these different options, and provide
configuration examples:
situations. The solution is to increase the radio coverage area. There are different options available that you
can use to increase the radio coverage area. These sections explain each of these different options, and provide
configuration examples:
Use APs in Repeater Mode
•
Use a Secondary AP in Access Point Mode with Non−overlapping Channels
•
Transmit Rate between AP and Client
•
Change the Transmitter Power Level Parameter of the Existing AP to Extend the Coverage
•
Position the APs Optimally
•
Distance
•
Obstructions
•
Interferences
•
Use APs in Repeater Mode
You can configure APs to act as repeaters. In this mode, the AP is not connected to the wired LAN. Instead,
the AP is placed within the radio range of the AP that is connected to the wired LAN (the root AP). In this
scenario, the repeater AP associates with the root AP, and extends the range of the radio coverage area. This
enables Wireless Clients that reside away from the root AP to gain access to the WLAN network. You can
configure either the 2.4 GHz radio or the 5 GHz radio as a repeater. In APs with two radios, only one radio
can be a repeater. You must configure the other radio as a root radio.
the AP is placed within the radio range of the AP that is connected to the wired LAN (the root AP). In this
scenario, the repeater AP associates with the root AP, and extends the range of the radio coverage area. This
enables Wireless Clients that reside away from the root AP to gain access to the WLAN network. You can
configure either the 2.4 GHz radio or the 5 GHz radio as a repeater. In APs with two radios, only one radio
can be a repeater. You must configure the other radio as a root radio.
When you configure an AP as a repeater, the Ethernet port on that AP does not forward traffic. The advantage
with the repeater mode in APs is that this mode helps to extend the radio coverage area of a WLAN in
situations where connectivity to the wired LAN is not possible. Also, there must be a fifty percent overlap in
coverage area with the root AP for the repeater mode to function.
with the repeater mode in APs is that this mode helps to extend the radio coverage area of a WLAN in
situations where connectivity to the wired LAN is not possible. Also, there must be a fifty percent overlap in
coverage area with the root AP for the repeater mode to function.
Repeater APs forward traffic from the wireless clients to either a wired AP or to another repeater AP. In cases
where there is a redundant path to the wired network, the repeater AP chooses the best path based on signal
strength and other performance−based parameters. By default, when there is more than one wired AP, the
repeater AP associates to the AP that has the best connectivity. On the other hand, you can also specify the AP
to which the repeater must associate manually.
where there is a redundant path to the wired network, the repeater AP chooses the best path based on signal
strength and other performance−based parameters. By default, when there is more than one wired AP, the
repeater AP associates to the AP that has the best connectivity. On the other hand, you can also specify the AP
to which the repeater must associate manually.
Repeater APs do have disadvantages. When you implement repeater APs in WLANs, the throughput of the
network decreases by half with every repeater AP that you add to the chain. This is because the repeater AP
must receive and then re−transmit each packet on the same channel. Another disadvantage is that a non−Cisco
wireless client device can face some problems when such a device tries to associate with repeater APs. You
must enable "Aironet extensions" on the parent (root) AP as well as the repeater APs when you set up APs in
repeated mode. Aironet extensions, which are enabled by default, improve the ability of the AP to understand
the capabilities of Cisco Aironet client devices associated with the AP. However, some of the non−Cisco
wireless clients do not work with Aironet extensions enabled on the APs. So, for WLAN environments where
you use a mixture of Cisco and non−Cisco clients, extension of the radio coverage through the repeater mode
APs is not a viable option.
network decreases by half with every repeater AP that you add to the chain. This is because the repeater AP
must receive and then re−transmit each packet on the same channel. Another disadvantage is that a non−Cisco
wireless client device can face some problems when such a device tries to associate with repeater APs. You
must enable "Aironet extensions" on the parent (root) AP as well as the repeater APs when you set up APs in
repeated mode. Aironet extensions, which are enabled by default, improve the ability of the AP to understand
the capabilities of Cisco Aironet client devices associated with the AP. However, some of the non−Cisco
wireless clients do not work with Aironet extensions enabled on the APs. So, for WLAN environments where
you use a mixture of Cisco and non−Cisco clients, extension of the radio coverage through the repeater mode
APs is not a viable option.
The next two sections explain with a configuration example how to set up repeater mode in APs.
Figure 1 Network Diagram for Method 1