ZyXEL Communications LTE6100, User Manual

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Chapter 7 Quality of Service (QoS)
LTE6100 User’s Guide
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The following table describes the labels in this screen.
7.6 QoS Technical Reference
This section provides some technical background information about the topics covered in this
chapter.
7.6.1 DiffServ
QoS is used to prioritize source-to-destination traffic flows. All packets in the flow are given the
same priority. You can use CoS (class of service) to give different priorities to different packet
types.
DiffServ (Differentiated Services) is a class of service (CoS) model that marks packets so that they
receive specific per-hop treatment at DiffServ-compliant network devices along the route based on
the application types and traffic flow. Packets are marked with DiffServ Code Points (DSCPs)
indicating the level of service desired. This allows the intermediary DiffServ-compliant network
devices to handle the packets differently depending on the code points without the need to
negotiate paths or remember state information for every flow. In addition, applications do not have
to request a particular service or give advanced notice of where the traffic is going.
DSCP and Per-Hop Behavior
DiffServ defines a new DS (Differentiated Services) field to replace the Type of Service (TOS) field
in the IP header. The DS field contains a 2-bit unused field and a 6-bit DSCP field which can define
up to 64 service levels. The following figure illustrates the DS field.
DSCP is backward compatible with the three precedence bits in the ToS octet so that non-DiffServ
compliant, ToS-enabled network device will not conflict with the DSCP mapping.
Table 20
Network Setting > QoS > Monitor
LABEL DESCRIPTION
Monitor
Refresh
Interval Select how often you want the LTE Device to update this screen. Select No Refresh to stop
refreshing statistics.
Status
# This is the index number of the entry.
Name This shows the name of the WAN interface on the LTE Device.
Pass Rate (bps) This shows how much traffic (bps) forwarded to this interface are transmitted successfully.
Queue Monitor
# This is the index number of the entry.
Name This shows the name of the queue.
Pass Rate (bps) This shows how much traffic (bps) assigned to this queue are transmitted successfully.
Drop Rate (bps) This shows how much traffic (bps) assigned to this queue are dropped.
DSCP (6 bits) Unused (2 bits)