Configuring Local Mesh Parameters; Configuring Wireless Backhaul Data Rate - Cisco Mesh Access Points Deployment Manual

Configuring Local Mesh Parameters

Configuring Local Mesh Parameters
After configuring global mesh parameters, you must configure the following local mesh parameters for these
specific features if in use in your network:
• Backhaul Data Rate. See the
• Ethernet Bridging. See the
• Bridge Group Name. See
• Workgroup Bridge. See the
• Public Safety Band Settings. See the
• Cisco 3200 Series Association and Interoperability. See the
• Power and Channel Setting. See
• Antenna Gain Settings. See the
• Dynamic Channel Assignment. See the

Configuring Wireless Backhaul Data Rate

Backhaul is used to create only the wireless connection between the access points. The backhaul interface by
default is 802.11a or 802.11a/n depending upon the access point. The rate selection is important for effective
use of the available RF spectrum. The rate can also affect the throughput of client devices, and throughput is
an important metric used by industry publications to evaluate vendor devices.
Dynamic Rate Adaptation (DRA) introduces a process to estimate optimal transmission rate for packet
transmissions. It is important to select rates correctly. If the rate is too high, packet transmissions fail resulting
in communication failure. If the rate is too low, the available channel bandwidth is not used, resulting in
inferior products, and the potential for catastrophic network congestion and collapse.
Data rates also affect the RF coverage and network performance. Lower data rates, for example 6 Mbps, can
extend farther from the access point than can higher data rates, for example 300 Mbps. As a result, the data
rate affects cell coverage and consequently the number of access points required. Different data rates are
achieved by sending a more redundant signal on the wireless link, allowing data to be easily recovered from
noise. The number of symbols sent out for a packet at the 1-Mbps data rate is higher than the number of
symbols used for the same packet at 11 Mbps. Therefore, sending data at the lower bit rates takes more time
than sending the equivalent data at a higher bit rate, resulting in reduced throughput.
In the controller release 5.2, the default data rate for the mesh 5-GHz backhaul is 24 Mbps. It remains the
same with 6.0 and 7.0 controller releases.
With the 6.0 controller release, mesh backhaul can be configured for 'Auto' data rate. Once configured, the
access point picks the highest rate where the next higher rate cannot be used because of conditions not being
suitable for that rate and not because of conditions that affect all rates. That is, once configured, each link is
free to settle down to the best possible rate for its link quality.
We recommend that you configure the mesh backhaul to Auto.
For example, if mesh backhaul chose 48 Mbps, then this decision is taken after ensuring that we cannot use
54 Mbps as there is not enough SNR for 54 and not because some just turned the microwave oven on which
affects all rates.
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Configuring Ethernet
theConfiguring Ethernet
their respective frequency bands that support WGB." section on page
Connecting the Cisco 1500 Series Mesh Access Points to the Network
Configuring Wireless Backhaul Data
Bridging.
Bridging.
Configuring Workgroup Bridges.
Configuring Public Safety Band
theConfiguring Power and Channel
Configuring Antenna Gain.
Configuring Dynamic Channel
Rate.
Settings.
"Table 34 identifies mesh access points and
180.
Settings.
Assignment.
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