WESM zl Management and Configuration Guide WT.01.03 and greater

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Introduction
ProCurve Wireless Edge Services zl Module
This chapter will discuss these features at a high level; to learn how to
configure them, see Chapter 4: “Wireless Local Area Networks (WLANs).”
SVP
SVP maintains a high QoS in the wireless network, specifically for VoWLAN
devices that are SVP-capable. SVP is implemented in wireless phone handsets,
wireless APs, and SpectraLink servers. This IEEE 802.11-compliant mecha-
nism minimizes latency for voice traffic by providing priority queues reserved
for voice packets and by increasing the probability that all voice packets are
transmitted in a predictable and timely manner.
If your network includes a SpectraLink server and SVP-capable phones, you
should enable SVP in the WLAN that includes these phones. RPs then
recognize SVP-encapsulated frames and handle them accordingly.
WMM
WMM is a more comprehensive QoS solution because it can provide differen-
tiated handling for any type of traffic based on its priority. Like 802.1p and
Differentiated Services (DiffServ) in Ethernet networks, WMM divides traffic
into multiple priority queues and then assigns different settings to each queue.
Although the types of settings dictated by the protocols are of course different
(as the shared wireless medium is different from the switched Ethernet
medium), the goal is the same: higher throughput for high priority traffic, as
well as lower latency for time-sensitive traffic.
The Wireless Edge Services zl Module can implement WMM on both down-
stream and upstream wireless traffic. To implement WMM on downstream
wireless traffic, the module sends settings for priority queues as part of a
radio’s configuration. To implement WMM on upstream wireless traffic, the
module configures RPs to send priority queue settings to wireless stations in
a particular WLAN.
You must enable WMM on a WLAN if you want RPs to prioritize downstream
traffic according to priority value. Enabling WMM also allows WMM-capable
wireless stations to prioritize upstream wireless traffic. By default, devices
prioritize traffic according to 802.1p priority. However, you can configure them
to use DiffServ values instead.
Figure 1-17 illustrates how the Wireless Edge Services zl Module can configure
RPs and wireless stations to prioritize mission-critical and VoWLAN traffic.