ZyXEL P-660HW-67 User Guide - Page 215

QoS Technical Reference

Page 215 highlights

Chapter 16 Quality of Service (QoS) Table 77 Advanced Setup > QoS > Class Setup (continued) LABEL DESCRIPTION 802.1p Remarking Select a priority level (0 to 7) to re-assign the priority level to matched traffic. Queue # Specify a queue tag to matched traffic. Traffic assigned to a higher queue gets through faster while traffic in lower queues is dropped when there is network congestion. Add Click this to add the rule. Delete Click this to remove the rule. Cancel Click this to restore previously saved settings. 16.5 QoS Technical Reference This section provides some technical background information about the topics covered in this chapter. 16.5.1 IEEE 802.1p IEEE 802.1p specifies the user priority field and defines up to eight separate traffic types. The following table describes the traffic types defined in the IEEE 802.1d standard (which incorporates the 802.1p). Table 78 IEEE 802.1p Priority Level and Traffic Type PRIORITY LEVEL TRAFFIC TYPE Level 7 Typically used for network control traffic such as router configuration messages. Level 6 Typically used for voice traffic that is especially sensitive to jitter (jitter is the variations in delay). Level 5 Typically used for video that consumes high bandwidth and is sensitive to jitter. Level 4 Typically used for controlled load, latency-sensitive traffic such as SNA (Systems Network Architecture) transactions. Level 3 Typically used for "excellent effort" or better than best effort and would include important business traffic that can tolerate some delay. Level 2 This is for "spare bandwidth". Level 1 This is typically used for non-critical "background" traffic such as bulk transfers that are allowed but that should not affect other applications and users. Level 0 Typically used for best-effort traffic. 16.5.2 IP Precedence Similar to IEEE 802.1p prioritization at layer-2, you can use IP precedence to prioritize packets in a layer-3 network. IP precedence uses three bits of the eight-bit ToS (Type of Service) field in the IP header. There are eight classes of services (ranging from zero to seven) in IP precedence. Zero is the lowest priority level and seven is the highest. ADSL Router Series User's Guide 215

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Chapter 16 Quality of Service (QoS)
ADSL Router Series User’s Guide
215
16.5
QoS Technical Reference
This section provides some technical background information about the topics covered in this
chapter.
16.5.1
IEEE 802.1p
IEEE 802.1p specifies the user priority field and defines up to eight separate traffic types. The
following table describes the traffic types defined in the IEEE 802.1d standard (which incorporates
the 802.1p).
16.5.2
IP Precedence
Similar to IEEE 802.1p prioritization at layer-2, you can use IP precedence to prioritize packets in a
layer-3 network. IP precedence uses three bits of the eight-bit ToS (Type of Service) field in the IP
header. There are eight classes of services (ranging from zero to seven) in IP precedence. Zero is
the lowest priority level and seven is the highest.
802.1p Remarking
Select a priority level (0 to 7) to re-assign the priority level to matched traffic.
Queue #
Specify a queue tag to matched traffic. Traffic assigned to a higher queue gets through
faster while traffic in lower queues is dropped when there is network congestion.
Add
Click this to add the rule.
Delete
Click this to remove the rule.
Cancel
Click this to restore previously saved settings.
Table 77
Advanced Setup > QoS > Class Setup (continued)
LABEL
DESCRIPTION
Table 78
IEEE 802.1p Priority Level and Traffic Type
PRIORITY
LEVEL
TRAFFIC TYPE
Level 7
Typically used for network control traffic such as router configuration messages.
Level 6
Typically used for voice traffic that is especially sensitive to jitter (jitter is the variations in
delay).
Level 5
Typically used for video that consumes high bandwidth and is sensitive to jitter.
Level 4
Typically used for controlled load, latency-sensitive traffic such as SNA (Systems Network
Architecture) transactions.
Level 3
Typically used for “excellent effort” or better than best effort and would include important
business traffic that can tolerate some delay.
Level 2
This is for “spare bandwidth”.
Level 1
This is typically used for non-critical “background” traffic such as bulk transfers that are
allowed but that should not affect other applications and users.
Level 0
Typically used for best-effort traffic.