Chapter 6 Wireless Configuration

ATC assigns priority based on packet size, since time-sensitive applications such as Internet telephony (Voice over IP or VoIP) tend to have smaller packet sizes than non-time sensitive applications such as FTP (File Transfer Protocol). The following table shows some common applications, their time sensitivity, and their typical data packet sizes. Note that the figures given are merely examples - sizes may differ according to application and circumstances.

Table 16 Typical Packet Sizes

APPLICATION

TIME

TYPICAL PACKET SIZE

SENSITIVITY

(BYTES)

 

Voice over IP (SIP)

High

< 250

 

 

 

Online Gaming

High

60 ~ 90

 

 

 

Web browsing (http)

Medium

300 ~ 600

 

 

 

FTP

Low

1500

 

 

 

When ATC is activated, the device sends traffic with smaller packets before traffic with larger packets if the network is congested.

ATC assigns priority to packets as shown in the following table.

Table 17 Automatic Traffic Classifier Priorities

PACKET SIZE (BYTES)

ATC PRIORITY

1 ~ 250

ATC_High

 

 

250 ~ 1100

ATC_Medium

 

 

1100 +

ATC_Low

 

 

You should activate ATC on the ZyXEL Device if your wireless network includes networking devices that do not support WMM QoS, or if you want to prioritize traffic but do not want to configure WMM QoS settings.

6.3.3 ATC+WMM

The ZyXEL Device can use a mapping mechanism to use both ATC and WMM QoS. The ATC+WMM function prioritizes all packets transmitted onto the wireless network using WMM QoS, and prioritizes all packets transmitted onto the wired network using ATC. See Section 8.2.2 on page 119 for details of how to configure ATC+WMM.

Use the ATC+WMM function if you want to do the following:

•enable WMM QoS on your wireless network and automatically assign a WMM priority to packets that do not already have one (see Section 6.3.3.1 on page 86).

•automatically prioritize all packets going from your wireless network to the wired network (see Section 6.3.3.2 on page 87).

6.3.3.1ATC+WMM from LAN to WLAN

ATC+WMM from LAN (the wired Local Area Network) to WLAN (the Wireless Local Area Network) allows WMM prioritization of packets that do not already have WMM QoS priorities assigned. The ZyXEL Device automatically classifies data packets using ATC and then assigns WMM priorities based on that ATC classification.

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ZyXEL NWA-3160 Series User’s Guide