Optimize APs O ver Low-Speed Links
Dependingo nyo urdeployment scenario, you may have APs or remote APs that connect to a controller located
across low-speed (less than 1Mbpscapacity) or high-latency (greater than 100ms)links.
With low-speed links,if heartbeator keep alive packets are not received between the A P and controller duringthe
definedi nterval,APs mayreboot c ausingclients tore-associat e. You can adjust the bootstrap threshold and
prioritize AP heartbeats to opti mize these types of links. In addition, high bandwidth applications may saturate low-
speed links.For example, if you have tunnel-mode SSIDs, use them with low-bandwidth applications such as barcode
scanning,small database lookups, and Telnet to avoid saturatingthe link. If you have traffic that willremain local,
deployingremote AP s andconfiguring SSIDs as bridge-mode SSIDs can also preventlink saturation.
With high-latencylinks, consider the amount and type of client devices ac cessing the links.D ellAP s locallyprocess
802.11 probe-requests andprobe-responses, but the 802.11 association process requires interaction with the
controller.
Whendeploying APs acrosslow-speed or high-latency links, Dell recommends the following best practices:
lConnect APs and Dell controllersover a link with a capacity of 1Mbps or greater.
lMaintain a minimum link speed of 64Kbpsper GRE tunneland per bridge-mode SSID. This is the minimum
speed requiredfor downloading software images.
lAdjust the bootstrap threshold to 30 if the network experiences packet loss. This makest heA P recover more
slowly in the event of a failure, but it will be more tolerant to heartbeatpacket loss.
lPrioritize AP heartbeats to preventlosing connectivity w ith the controller.
lIf possible, reducethe number of tunnel-modeSSID s. Each SSID creates a tunnelto t heco ntrollerwith its o wn
tunnelkeep alive traffic.
lIf most of the data traffic will remain localto thesit e,deploy remote AP s in bridgingmode. For more
information about remote APs, see Access Po ints (APs) on page 393.
lIf high-latencylinks such as transoceanic or satellite links areused in the network, deploy a controller
geographicallyclose to the AP s.
lIf high-latencycauses association issues with certain handheld devices or barcode scanners, check the
manufacturerof the device for recent firmware and driver updates.

Configuring the Bootstrap Threshold

To configuret heboo tstrap thresholdusing the WebUI:
1. Navigate to the Configuration >Wir eless > AP Configuration page.
2. Select either the AP Gro upor A P Specifict ab. Click Edit byt heAP group or AP name.
The AP system profile configuration settings are divided into two tabs,Basic and Advanced. The Basic tab
displays onlyt hose configurationsetti ngsthat o ftenneed to be adjusted to suit a specific network. The
Advanced tab shows all configuration settings, including settings that do not needfrequent adjustment or should
be kept at their defaultvalues. If you change a setting on one tab then click and display the other tab without
saving your configuration, that setting will revert to its previousvalue. Both basic and advanced settings are
described in Table 120.
3. Under Profiles, select AP, then AP system profile. The profile appears the Profile Details wi ndow.
4. In the Bootstr ap threshold field, enter3 0.
5. Click Apply.
DellPowerConnect W- Series ArubaOS 6.2 | User Guide AccessPoints(APs) | 417