ADS-TEC RAP/RAC1000 User Manual - Manual (Page 160)

IT Infrastructure RAP/RAC1000
160
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12 E XAMPLES OF U SE
12.1 P RIORITIZATION
G ENERAL
Nowadays a great many different types of data are transmitted via communication
networks and the data volumes also constantly increase. Prioritization allows to allocate
varying high transmission rates to the different types of data and thus to avoid that
downloading has a negative impact on a VoIP connection. Compared to wired networks,
WLAN is restricted by a smaller data throughput. Therefore prioritization is particularly
advisable here.
U
PGRADES FROM 802.11 E
In addition to a user-controlled prioritization, the RAP/RAC devices from ads-tec also make
the QoS upgrades of 802.11e standard. These upgrades are permanently active. The
802.11e standard defines four classes out which the Voice standard has top priority:
• Best Effort
• Background
• Video
• Voice
For the purpose of classification, the Type of Service box is evaluated according to the
following table:
IP ToS 802.11e Class
0x20
Background
0x40
0x80
Video
0xA0
0xC0
Voice
0xE0
0x88
0xB8
Others Best
Effort
If now various data connections are active at the same time, a VoIP connection can
preferably be transmitted via the Type of Service box (e.g.: on 0xC0).
Note:
The 802.11e Prioritization is applicable to outbound packets only.
The 802.11e upgrades are always active and are thus also available without configuration.
The required settings for a user-controlled prioritization will be explained below.