Grandstream Networks WP820 Application Note

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WP820 Wi-Fi Roaming Application Note
Unicast Mode and Multicast Mode
In unicast mode, the controller unicasts every multicast packet to every access point associated to the controller.
In multicast mode, the controller sends multicast packets to a CAPWAP multicast group. This method reduces
overhead on the controller processor and shifts the work of packet replication to your network. It’s recommended
to use unicast mode to ensure call quality.
WMM (Wi-Fi Multimedia)
WMM is a wireless QoS protocol, a subset of the 802.11e protocol. It is used to ensure that packets with high
priority can be sent first so that service quality for voice, video and other applications can be guaranteed.
On WP820, WMM related configurations can be found undero web UI->Network Settings->Advanced Network
Settings.
 Layer 3 QoS for SIP
This defines the layer 3 packet’s QoS parameter for SIP messages in decimal pattern. The value is used
for IP Precedence, Diff-Serv or MPLS. The default setting is 26 which is equivalent to the DSCP name
constant CS6.
 Layer 3 QoS for Audio
This defines the layer 3 packet’s QoS parameter for RTP messages in decimal pattern. This value is used
for IP Precedence, Diff-Serv or MPLS. The default setting is 46 which is equivalent to the DSCP name
constant CS6.
WP820 will convert the QoS value to the corresponding WMM value/level so the packets can be differentiated
and handled properly by other network devices.
Band Steering
Dual band operation with Band Steering detects clients capable of 5 GHz operation and steers them to that
frequency which leaves the more crowded 2.4 GHz band available for legacy clients. This helps improve end
user experience by reducing channel utilization, especially in high density environments. It’s recommended to
enable band steering on the APs, which means by default 5Ghz should be used (users can switch to 2.4Ghz
if 5Ghz signal is poor.)
For above important parameters, the following sections provide the configuration methods on APs from different
vendors for network administrator’s quick reference. The following table shows whether the AP has the
configurations related to these parameters. Click on the brand name to quickly locate relevant configuration
instructions.

Grandstream Networks WP820 Specifications

General

Brand	Grandstream Networks
Model	WP820
Category	Cordless Telephone
Language	English