Aruba Networks AirOS v2.3, User Manual

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Configuring Quality of Service for Voice Applications 191
Chapter 12
C
HAPTER
12
Configuring Quality of
Service
for Voice Applications
This document outlines the steps required to configure QoS on an Aruba WLAN Switch for
voice devices, including SIP phones and SVP phones. Since voice applications are more
vulnerable to delay and jitter, the network infrastructure should be able to prioritize the voice
traffic over the data traffic.
The central concept of an Aruba WLAN Switch is of a role. The role of any wireless client
determines its privileges including the priority that every type of traffic to/from the client gets
in the wireless network. Thus the QoS configuration for voice applications is mostly done as
part of the firewall roles and policies configuration (refer to the Configuring Firewall roles and
policies document for more details).
Thus in an Aruba system, the administrator can configure two roles – one for clients that do
mostly data traffic such as laptops, and the other for clients that do mostly voice traffic such as
VoIP phones. There are different means for the client to derive a role (refer to Configuring
Firewall roles and policies for more details). In most cases, the users on the data traffic will be
assigned a role after they get authenticated by using an authentication mechanism such as
802.1x or VPN or captive portal. The role for the VoIP phones can be derived from the OUI of
their MAC addresses or the SSID they associate to. This role will typically be configured to
have access allowed only for the voice protocol being used (for instance: SIP, SVP etc.).
The section below shows the steps to configure an Aruba network for the two roles with the
required privileges (the allowed protocols etc.) and the priorities assigned to different types of
traffic.