ZyXEL Communications Corporation VMG1312B10C Manuel D’Utilisation
Chapter 9 Quality of Service (QoS)
VMG1312-B10C User’s Guide
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9.8 Technical Reference
The following section contains additional technical information about the Device features described
in this chapter.
in this chapter.
IEEE 802.1Q Tag
The IEEE 802.1Q standard defines an explicit VLAN tag in the MAC header to identify the VLAN
membership of a frame across bridges. A VLAN tag includes the 12-bit VLAN ID and 3-bit user
priority. The VLAN ID associates a frame with a specific VLAN and provides the information that
devices need to process the frame across the network.
membership of a frame across bridges. A VLAN tag includes the 12-bit VLAN ID and 3-bit user
priority. The VLAN ID associates a frame with a specific VLAN and provides the information that
devices need to process the frame across the network.
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).
following table describes the traffic types defined in the IEEE 802.1d standard (which incorporates
the 802.1p).
Name
This shows the name of the interface on the Device.
Pass Rate
This shows how many packets forwarded to this interface are transmitted successfully.
Drop Rate
This shows how many packets forwarded to this interface are dropped.
Queue Monitor
#
This is the index number of the entry.
Name
This shows the name of the queue.
Pass Rate
This shows how many packets assigned to this queue are transmitted successfully.
Drop Rate
This shows how many packets assigned to this queue are dropped.
Table 50
Network Setting > QoS > Monitor (continued)
LABEL
DESCRIPTION
Table 51
IEEE 802.1p Priority Level and Traffic Type
PRIORITY
LEVEL
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).
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.
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.
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.
are allowed but that should not affect other applications and users.
Level 0
Typically used for best-effort traffic.