Allied Telesis x900-48 series Instruction and safety manual

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AlliedWareTM OS
How To |
Introduction
This document describes some generic configuration examples for Quality of Service (QoS)
on AT-9900 and x900 series switches running the AlliedWare OS.
What information will you find in this document?
This document provides information on the following sections:
z" 1 . Setting the egress rate" on page 2
z"2. Setting the priority on a packet" on page 7
z"3. Setting the egress queues" on page 10
z"Full QoS scenario 1 : tiered services for a single customer" on page 13
z"Full QoS scenario 2: bandwidth limiting of multiple customers" on page 18
Which product and software version does this information apply to?
This How To Note applies to the following Allied Telesis switches, running the AlliedWare
OS software version 2.7.
1 or later:
zAT-9924SP, AT-9924T, AT-9924T/4SP
zx900-48 series
zx900-24 series
zAT-8948
Configure QoS on AT-9900, x900-48, and x900-24
Series Switches

Page 2 | AlliedWare™ OS How To Note: QoS configuration
1 . Setting the egress rate
1 . Setting the egress rate
Example 1 - 1 : Setting the egress limit of a switch port
Command:
set switch port=24 egresslimit=640
This command will set the egress limit of port 24 to 640kbps. The granularity is 640kbps.
Port 24

Page 3 | AlliedWare™ OS How To Note: QoS configuration
1 . Setting the egress rate
Example 1 -2: setting the maximum bandwidth limit per ingress port
Ingress rate limiting cannot be configured on the port per se, but is achieved by creating a
QoS policy with a bandwidth limited traffic class, and applying that policy to each port.
This set of commands will set the ingress rate of traffic received per port from ports
1 to 20
to various different values. Note that classifier=
1 matches every packet. The granularity of
the rate limiting is around
1 kbps.
create class=1
create qos flow=1
add qos flow=1 class=1
create qos traff=1
add qos traff=1 flow=1
set qos traff=1 maxbandwidth=128kbps maxburst=5kbyte dropbw=yes
create qos poli=1
add qos poli=1 traff=1
set qos port=1 poli=1
create qos flow=2
add qos flow=2 class=1
create qos traff=2
add qos traff=2 flow=2
set qos traff=2 maxbandwidth=256kbps maxburst=5kbyte dropbw=yes
create qos poli=2
add qos poli=2 traff=2
set qos port=2 poli=2
create qos flow=3
add qos flow=3 class=1
create qos traff=3
add qos traff=3 flow=3 remarking=priority
set qos traff=3 maxbandwidth=64kbps maxburst=5kbyte dropbw=yes
create qos poli=3
add qos poli=3 traff=3
set qos port=3 poli=3
...
Port 24
Ingress ports 1-20

Page 4 | AlliedWare™ OS How To Note: QoS configuration
1 . Setting the egress rate
Example 1 -3: Setting the maximum bandwidth limit for each user
In example 1 - 1 , we configured an egress rate on ports. But the granularity of that bandwidth
limiting was multiples of 640kbps. To achieve a finer-grained limiting on egress, it is necessary
to make use of traffic classes. In this example we assume that there is one device with a
known IP address, attached to each port. A traffic class will be created for each such IP
address, and a maximum bandwidth applied to the traffic class.
This set of commands will set the total egress limit (download traffic) for each user to
256kbps. The granularity is around
1 kbps.
create class=1 ipda=192.168.1.1
create class=2 ipda=192.168.1.2
create class=3 ipda=192.168.1.3
...
create qos flow=1
add qos flow=1 class=1
create qos traf=1
add qos traf=1 flow=1
set qos traf=1 maxbandw=256kbps maxburst=5kbyte dropbw=yes
create qos flow=2
add qos flow=2 class=2
create qos traf=2
add qos traf=2 flow=2
set qos traf=2 maxbandw=256kbps maxburst=5kbyte dropbw=yes
create qos flow=3
add qos flow=3 class=3
create qos traf=3
add qos traf=3 flow=3
set qos traf=3 maxbandw=256kbps maxburst=5kbyte dropbw=yes
...
create qos poli=1
add qos poli=1 traff=1-23
set qos port=24 poli=1
Port 24
Internet
connection
Users connected to the switch downloading files fromthe Internet
(192.168.1.1-192.168.1.25)

Page 5 | AlliedWare™ OS How To Note: QoS configuration
1 . Setting the egress rate
Example 1 -4: Setting the maximum bandwidth limit for each IP subnet
This example is very similar to example 1 -3, except that it is assumed that a whole subnet is
attached to each port, not just a single device on each port.
This set of commands will set the total egress limit (download traffic) for each subnet to
256kbps. The granularity is around
1 kbps.
create class=1 ipda=192.168.1.0/24
create class=2 ipda=192.168.2.0/24
create class=3 ipda=192.168.3.0/24
...
create qos flow=1
add qos flow=1 class=1
create qos traf=1
add qos traf=1 flow=1
set qos traf=1 maxbandw=256kbps maxburst=5kbyte dropbw=yes
create qos flow=2
add qos flow=2 class=2
create qos traf=2
add qos traf=2 flow=2
set qos traf=2 maxbandw=256kbps maxburst=5kbyte dropbw=yes
create qos flow=3
add qos flow=3 class=3
create qos traf=3
add qos traf=3 flow=3
set qos traf=3 maxbandw=256kbps maxburst=5kbyte dropbw=yes
...
create qos poli=1
add qos poli=1 traff=1-23
set qos port=24 poli=1
Port 24
Internet
connection
Users connected to the switch downloading files fromthe Internet
(192.168.1.0/24 - 192.168.23.0/24)

Page 6 | AlliedWare™ OS How To Note: QoS configuration
1 . Setting the egress rate
Example 1 -5: Setting the maximum bandwidth limit of VLANs
Note: The portgroup feature is not supported before software release v2.7.5. If using an
earlier software release, use the port parameter on the policy instead.
create class=1 vlan=2
create class=2 vlan=3
create class=3 vlan=4
create qos flow=1
add qos flow=1 class=1
create qos flow=2
add qos flow=2 class=2
create qos flow=3
add qos flow=3 class=3
create qos traff=1
add qos traff=1 flow=1
set qos traff=1 maxbandw=256kbps maxburst=5kbyte dropbw=yes
create qos traff=2
add qos traff=2 flow=2
set qos traff=2 maxbandw=256kbps maxburst=5kbyte dropbw=yes
create qos traff=3
add qos traff=3 flow=3
set qos traff=3 maxbandw=256kbps maxburst=5kbyte dropbw=yes
create qos poli=1
add qos poli=1 traff=1,2,3
create qos portgroup=1 ports=1-20
set qos portgroup=1 policy=1
Port 24
Ingress ports 1-20 (these ports are carrying a mixture of
VLAN2, VLAN3 and VLAN4 packets, either with or without VLAN tags)

Page 7 | AlliedWare™ OS How To Note: QoS configuration
2. Setting the priority on a packet
2. Setting the priority on a packet
Example 2- 1 : Setting the Layer 2 (VLAN/802. 1 p) priority per ingress port
Here we assign different 802. 1 p values to packets arriving on different ports.
These values are also known as the Layer 2 (L2) or VLAN priority.
create class=1
create qos flow=1
add qos flow=1 class=1
create qos traff=1
add qos traff=1 flow=1
set qos traff=1 mark=11 premarking=usemark
set qos dscpmap=premarking dscp=11 newpriority=6
create qos poli=1
add qos poli=1 traff=1
set qos port=1 poli=1
create class=2
create qos flow=2
add qos flow=2 class=2
create qos traff=2
add qos traff=2 flow=2
set qos traff=2 mark=12 premarking=usemark
set qos dscpmap=premarking dscp=12 newpriority=5
create qos poli=2
add qos poli=2 traff=2
set qos port=2 poli=2
create class=3
create qos flow=3
add qos flow=3 class=3
create qos traff=3
add qos traff=3 flow=3 remarking=priority
set qos traff=3 mark=13 premarking=usemark
set qos dscpmap=premarking dscp=13 newpriority=4
create qos poli=3
add qos poli=3 traff=3
set qos port=3 poli=3
...
Port 24
Ingress ports 1-20 (these ports MAY be carrying a mixture of
packets fromdifferent VLAN packets, either with or without VLAN tags)

Page 8 | AlliedWare™ OS How To Note: QoS configuration
2. Setting the priority on a packet
Example 2-2: Setting the Layer 2 (VLAN/802. 1 p) priority per VLAN
This set of commands will set the Layer 2 priority of VLAN2, VLAN3 and VLAN4 traffics
packets, received on ports
1 to 20, to 6, 5 and 4 respectively.
create class=1 vlan=2
create class=2 vlan=3
create class=3 vlan=4
create qos flow=1
add qos flow=1 class=1
create qos flow=2
add qos flow=2 class=2
create qos flow=3
add qos flow=3 class=3
create qos traff=1
add qos traff=1 flow=1
set qos traff=1 mark=11 premarking=usemark
set qos dscpmap=premarking dscp=11 newpriority=6
create qos traff=2
add qos traff=2 flow=2
set qos traff=2 mark=12 premarking=usemark
set qos dscpmap=premarking dscp=12 newpriority=5
create qos traff=3
add qos traff=3 flow=3 remarking=priority
set qos traff=3 mark=13 premarking=usemark
set qos dscpmap=premarking dscp=13 newpriority=4
create qos poli=1
add qos poli=1 traff=1,2,3
set qos port=1-20 poli=1
Port 24
Ingress ports 1-20 (these ports MAY be carrying a mixture ofVLAN2,
VLAN3, and VLAN4 packets either with or without VLAN tags)

Page 9 | AlliedWare™ OS How To Note: QoS configuration
2. Setting the priority on a packet
Example 2-3: Setting the Layer 3 (TOS/DCSP) priority per ingress port
Use the same configuration provided in Example 2- 1 on page 7, but change the following line:
set qos dscpmap=premarking dscp=<incoming-dscp> newpriority=<new-
priority>
to
set qos dscpmap=premarking dscp=<incoming-dscp> newdscp=<new-value>
Example 2-4: Setting the Layer 3 (TOS/DSCP) priority per VLAN
Use the same configuration provided in Example 2-2 on page 8, but change the following line:
set qos dscpmap=premarking dscp=<incoming-dscp> newpriority=<new-
priority>
to
set qos dscpmap=premarking dscp=<incoming-dscp> newdscp=<new-dscp>

Page 10 | AlliedWare™ OS How To Note: QoS configuration
3. Setting the egress queues
3. Setting the egress queues
In this section we look at methods for directing certain packets into certain queues on the
egress port.
Example 3- 1 : Setting the egress queue according to the L2 priority of the
incoming packet
The priority-to-queue map is a straightforward method for assigning packets to egress on the
basis of the packets’ 802.
1 p values.
Command
settings
The first command sets the mapping between the VLAN Tag User Priorities of the packets
and the egress queues. Priorities 0 to 7 are mapped to queues 2, 3,
1 , 0, 4, 5, 6 and 7
respectively.
The second command sets the incoming ports to send untagged packets to queue number 2,
which means the untagged packets will use the same queue as the tagged packets with a User
Priority of
1 .
set qos prio2queuemap=2,3,1,0,4,5,6,7
set qos port=1-20 defaultque=2
Port 24
Ingress ports 1-20 (these ports MAY be carrying a mixture ofpackets
fromdifferent VLAN packets either with or without VLAN tags)

Page 11 | AlliedWare™ OS How To Note: QoS configuration
3. Setting the egress queues
Example 3-2: Setting the egress queue according to the ingress port
This set of commands will set the egress queue of any traffic received from port 1 to egress
queue 6, from port 2 to egress queue 5, etc.
create class=1
create qos flow=1
add qos flow=1 class=1
create qos traff=1
add qos traff=1 flow=1
set qos traff=1 mark=11 premarking=usemark
set qos dscpmap=premarking dscp=11 newqueue=6
create qos poli=1
add qos poli=1 traff=1
set qos port=1 poli=1
create qos flow=2
add qos flow=2 class=1
create qos traff=2
add qos traff=2 flow=2
set qos traff=2 mark=12 premarking=usemark
set qos dscpmap=premarking dscp=12 newqueue=5
create qos poli=2
add qos poli=2 traff=2
set qos port=2 poli=2
create qos flow=3
add qos flow=3 class=1
create qos traff=3
add qos traff=3 flow=3 remarking=priority
set qos traff=3 mark=13 premarking=usemark
set qos dscpmap=premarking dscp=13 newqueue=4
create qos poli=3
add qos poli=3 traff=3
set qos port=3 poli=3
...
Port 24
Ingress ports 1-20 (these ports MAY be carrying a mixture ofpackets
fromdifferent VLAN packets either with or without VLAN tags)

Page 12 | AlliedWare™ OS How To Note: QoS configuration
3. Setting the egress queues
Example 3-3: Configuring WRR for egress queues
This example is used for configuring WRR on egress queues according to the ingress port of
the traffic.
This set of commands will set the egress queue of any traffic received from port
1 to egress
queue 6, from port 2 to egress queue 5 and from port 3 to egress queue 4. And on egress,
the WRR algorithm will do the following: for every 4 packets from queue 6, 2 packets will
leave queue 5 and
1 packet will leave queue 4.
create class=1
create qos flow=1
add qos flow=1 class=1
create qos traff=1
add qos traff=1 flow=1
set qos traff=1 mark=11 premarking=usemark
set qos dscpmap=premarking dscp=11 newqueue=6
create qos poli=1
add qos poli=1 traff=1
set qos port=1 poli=1
create qos flow=2
add qos flow=2 class=1
create qos traff=2
add qos traff=2 flow=2
set qos traff=2 mark=12 premarking=usemark
set qos dscpmap=premarking dscp=12 newqueue=5
create qos poli=2
add qos poli=2 traff=2
set qos port=2 poli=2
create qos flow=3
add qos flow=3 class=1
create qos traff=3
add qos traff=3 flow=3 remarking=priority
set qos traff=3 mark=13 premarking=usemark
set qos dscpmap=premarking dscp=13 newqueue=4
create qos poli=3
add qos poli=3 traff=3
set qos port=3 poli=3
set qos port=24 egressque=6 schedu=wrr1 wrrweight=24
set qos port=24 egressque=5 schedu=wrr1 wrrweight=12
set qos port=24 egressque=4 schedu=wrr1 wrrweight=6
Port 24
Ingress ports 1-3 (these ports MAY be carrying a mixture ofpackets
fromdifferent VLAN packets either with or without VLAN tags)

Page 13 | AlliedWare™ OS How To Note: QoS configuration
Full QoS scenario 1 : tiered services for a single customer
Full QoS scenario 1 : tiered services for a single
customer
In this section, we will build up a relatively complex QoS configuration to support a scenario
requiring quite precise control over the traffic passing through the switch.
The scenario is an ISP providing connectivity for a customer, and offering different levels of
service for different types of traffic.
The customer is connected to port
1 of the switch, and the uplink to the ISP is on port 24 of
the switch.
The service offered by the ISP puts a limit on the total bandwidth of traffic that the customer
can send to the ISP.
This is achieved by setting a maximum bandwidth on the uplink port:
set switch port=24 egresslimit=<limit>
The deal offered to the customer is that their traffic will be treated as belonging to three
categories, and each category of traffic will be given a different level of service:
Gold traffic will be limited to, say, 2Mbps, but the ISP will guarantee delivery of the traffic
across their network, with a low latency.
Silver traffic will not have a particular limit (i.e. it can burst up to the max egress bandwidth
of the uplink port), but when congestion occurs, it will be throttled back in favour of Gold
traffic, if necessary. The ISP will guarantee to deliver up to, say 5Mbps of Silver traffic across
its network 90% of the time, but will give no guarantees about latency.
XStep 1 —Set the egress bandwidth limiting
XStep 2—Give better service to some types of traffic than to others
Port 24
uplink to the ISP
Customer LAN
ISP

Page 14 | AlliedWare™ OS How To Note: QoS configuration
Full QoS scenario 1 : tiered services for a single customer
Bronze traffic is also allowed to burst up to the full egress bandwidth of the uplink port,
but when congestion occurs, will be throttled back in favour of Gold traffic, and will share the
remaining bandwidth with Silver traffic in a Weighted Round Robin fashion. The ISP makes no
guarantees at all with regard to delivery of Bronze traffic across their network; it will be
delivered on a best-effort basis.
Identify the types of traffic
The different categories of traffic will be identified by the DSCP values in the packets'
headers. It is up to the customer to mark the packets with the appropriate DSCP values.
The DSCP values belonging to the different traffic categories are:
The classifiers to match these DSCP values are:
create classifier=1 ipds=0
create classifier=2 ipds=30
create classifier=3 ipds=40
There are 3 flow groups created, and the appropriate classifiers are added to each flow
group:
create qos flowgroup=1
create qos flowgroup=2
create qos flowgroup=3
add qos flowgroup=1 classifier=1
add qos flowgroup=2 classifier=2
add qos flowgroup=3 classifier=3
Then three traffic classes are created, each containing one flow group:
create qos trafficclass=1
create qos trafficclass=2
create qos trafficclass=3
add qos trafficclass=1 flowgroup=1
add qos trafficclass=2 flowgroup=2
add qos trafficclass=3 flowgroup=3
create qos policy=1
add qos policy=1 traffic=1,2,3
set qos port=1 policy=1
This way, each category of traffic is associated with a different traffic class.
Gold 40
Silver 30
Bronze 0
XPut the different categories of trafffic into different queues

Page 15 | AlliedWare™ OS How To Note: QoS configuration
Full QoS scenario 1 : tiered services for a single customer
The act of assigning packets in a particular traffic class to a particular egress queue is achieved
in the pre-marking process. This requires that the pre-marking DSCP map table be set up to
send packets to appropriate queues, based on their DSCP value:
set qos dscpmap=premark dscp=0 newqueue=1
set qos dscpmap=premark dscp=30 newqueue=2
set qos dscpmap=premark dscp=40 newqueue=6
The traffic classes all need to be configured to use the DSCP value in the incoming packet as
the index to use in looking up this premarking table:
set qos trafficclass=1 premark=usedscp
set qos trafficclass=2 premark=usedscp
set qos trafficclass=3 premark=usedscp
The premarking process will use the DSCP map to decide which egress queue to direct the
packets into, but that will only be of any use if the egress queues have been set up with the
required properties.
What is required is that:
Gold traffic ALWAYS has precedence over Silver or Bronze traffic. So, when a Gold packet
arrives at the egress port, it is transmitted immediately, irrespective of how many Silver or
Bronze packets might be queued up.
When there are Silver and Bronze packets queued up, they are transmitted according to a
Weighted Round Robin (WRR) scheme.
This is achieved by ensuring that the egress queue to which Gold traffic is directed to is a
priority queue, and the egress queues to which the silver and bronze traffic are directed are
WRR queues.
Actually, we also want to set the egress queue for the packets generated by the switch's CPU
(like STP, BGP, OSPF …) to queue 7, and make this the highest priority queue of all, to
prevent any loss of these packets.
set switch cputxque=7
So, we need to specify the queue types of queues 1 , 2, 6, 7 on port 24:
set qos port=24 egressqueue=6,7 scheduler=strict
set qos port=24 egressqueue=1,2 scheduler=WRR1
The relative weights to give to Silver and Bronze traffic are set by specifying the WRR weight
for their queues. For example, to give a 4:
1 ratio of Silver to Bronze traffic:
set qos port=24 egressqueue=1 wrrweight=1
set qos port=24 egressqueue=2 wrrweight=4
XSet the required properties on the egress queues

Page 16 | AlliedWare™ OS How To Note: QoS configuration
Full QoS scenario 1 : tiered services for a single customer
The Gold traffic must be strictly limited to 2Mbps
This is achieved by configuring a maxbandwidth on that traffic class, and dropping
bandwidthclass 3 traffic:
set qos trafficclass=3 maxbandwidth=2mbps maxburst=20Kbytes
dropbwclass3=true
For silver traffic, there is preferential treatment for the first 5Mbps of traffic. So, when there
is congestion, you want to still be getting 5Mbps of Silver traffic through, if possible.
This is achieved by putting bandwidth limits on both Silver and Bronze traffic, and using RED
curves to shape the throughput back to those limits when congestion occurs.
set qos trafficclass=2 maxbandwidth=5Mbps maxburst=30Kbytes
set qos trafficclass=1 maxbandwidth=<egresslimit-7> maxburst=<burst>
set qos red=1 queue=2 start1=40KB stop1=60KB start2=7KB stop2=12KB
start3=5KB stop3=10KB
set qos red=1 queue=1 start1=20KB stop1=50KB start2=5KB stop2=10KB
start3=2KB stop3=6KB
set qos port=24 red=1
XStep 3—Set the bandwidth limits

Page 17 | AlliedWare™ OS How To Note: QoS configuration
Full QoS scenario 1 : tiered services for a single customer
RED curves—a refresher
Random Early Discard curves are bandwidth class aware, and can drop lower priority packets
when severe congestion occurs, with progressively more and higher priority packets dropped
until congestion is eased. This is useful for TCP flows, because the sender will slow the rate
of transmission when it detects a packet loss.
These curves are very lenient on green traffic, but will quickly start dropping yellow and red
traffic when congestion occurs.
Colours ofpackets over time
Minburst bucket Maxburst bucket
12K
228K
216K
48K
132K
204K
96K
144K
24K
36K
60K
72K
108K
120K
156K
168K
180K
192K
0
Bits
123456789
Seconds
E1
E2E3
C4
C5E6E7
Minbandwidth

Page 18 | AlliedWare™ OS How To Note: QoS configuration
Full QoS scenario 2: bandwidth limiting of multiple customers
Full QoS scenario 2: bandwidth limiting of
multiple customers
In this section, we will build up another relatively complex QoS configuration to support a
different scenario.
The scenario is an ISP providing connectivity for several independent customers (one per
port). Different customers have signed up for different deals that provide different levels of
service.
In this example, to keep things simple, we will just consider the customers connected to
ports
1 -5 of the switch.
Also, we will assume that port 24 provides the uplink connection to the Internet.
First, let us consider the basic bandwidth limit that has been imposed on each customer:
XStep 1 —Bandwidth limiting
Port IP address Bandwidth limit
1 2 1 2. 1 2. 1 2. 11 Mbps
22
1 2. 1 2. 1 2.2 1 0Mbps
32
1 2. 1 2. 1 2.3 1 5Mbps
42
1 2. 1 2. 1 2.4 5Mbps
52
1 2. 1 2. 1 2.5 2Mbps
Port 24
uplink to the ISP
Customers 1-5
Ports 1-5
Internet

Page 19 | AlliedWare™ OS How To Note: QoS configuration
Full QoS scenario 2: bandwidth limiting of multiple customers
The configuration required to impose these bandwidth limits would be:
Limiting the outgoing traffic:
create qos policy=1 dtcdropbwclass3=yes dtcmaxbandwidth=1Mbps
dtcmaxburst=10Kb
create qos policy=2 dtcdropbwclass3=yes dtcmaxbandwidth=10Mbps
dtcmaxburst=10Kb
create qos policy=3 dtcdropbwclass3=yes dtcmaxbandwidth=15Mbps
dtcmaxburst=10Kb
create qos policy=4 dtcdropbwclass3=yes dtcmaxbandwidth=5Mbps
dtcmaxburst=10Kb
create qos policy=5 dtcdropbwclass3=yes dtcmaxbandwidth=2Mbps
dtcmaxburst=10Kb
set qos port=1 poli=1
set qos port=2 poli=2
set qos port=3 poli=3
set qos port=4 poli=4
set qos port=5 poli=5
Limiting the incoming traffic:
create class=6 ipda=212.12.12.1
create class=7 ipda=212.12.12.2
create class=8 ipda=212.12.12.3
create class=9 ipda=212.12.12.4
create class=10 ipda=212.12.12.5
create qos flow=6
add qos flow=6 class=6
create qos flow=7
add qos flow=7 class=7
create qos flow=8
add qos flow=8 class=8
create qos flow=9
add qos flow=9 class=9
create qos flow=10
add qos flow=10 class=10
create qos traff=6
set qos traff=6 maxband=1Mbps maxburst=10Kb dropbwc=yes
add qos traff=6 flow=6
create qos traff=7
set qos traff=7 maxband=10Mbps maxburst=10Kb dropbwc=yes
add qos traff=7 flow=7
create qos traff=8
set qos traff=8 maxband=15Mbps maxburst=10Kb dropbwc=yes
add qos traff=8 flow=8

Page 20 | AlliedWare™ OS How To Note: QoS configuration
Full QoS scenario 2: bandwidth limiting of multiple customers
create qos traff=9
set qos traff=9 maxband=5Mbps maxburst=10Kb dropbwc=yes
add qos traff=9 flow=9
create qos traff=10
set qos traff=10 maxband=2Mbps maxburst=10Kb dropbwc=yes
add qos traff=10 flow=10
create qos poli=6
add qos poli=6 traff=6-10
set qos port=24 poli=6
The ISP can offer to the customer a guarantee that VoIP traffic (up to a certain, relatively low,
bandwidth) will be given preferential treatment.
So, for each port, VoIP traffic will be classified into its own traffic class, and directed to a high-
priority egress queue.
Therefore, we need to classify VoIP traffic
create classifier=11 udpdport=5060
create classifier=12 udpdport=5061
create classifier=13 udpdport=5004 udpdmask=FFFE
create classifier=14 udpdport=16384 udpdmask=8000
The VoIP traffic needs to be associated to a traffic class that applies a strict max bandwidth,
and uses the premarking DSCP map to assign the traffic to a high priority queue (and to mark
the DSCP fields of the packets, for good measure).
set qos dscpmap=premarking dscp=55 newqueu=6 newdscp=55
So, the configuration for the QoS to be applied to the outgoing traffic now becomes:
set qos dscpmap=premarking dscp=55 newqueu=6 newdscp=55
create classifier=11 udpdport=5060
create classifier=12 udpdport=5061
create classifier=13 udpdport=5004 udpdmask=FFFE
create classifier=14 udpdport=16384 udpdmask=8000
create qos flow=1
add qos flow=1 class=11-14
create qos traffic=1 markvalue=55 premark=usemarkvalue
set qos traffic=1 maxband=64Kbps dropbwclass3=yes maxburst=10kbytes
XStep 2—Giving better service to VOIP traffic