Shiro ADSL 2/2+ Ethernet Modem User Manual

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User Manual 
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The rules are: 
1.  CoS1 has absolute priority and is used for expedited forwarding (EF) traffic. This is always 
serviced till completion. 
2.  CoS2-CoS5 is used for assured forwarding (AF) classes. They are serviced in a strict round 
robin manner using the following priority scheme: 
CoS2 > CoS3 > CoS4 > CoS5 
3.  CoS6 is for best effort (BE) traffic. This is only serviced when there is no other class of service. 
If QoS is not enabled on your router, all traffic will be treated as best effort. 
There are some additional terms you should get familiarize with: 
 
Ingress: Packets arriving into the router from a WAN/LAN interface. 
 
Egress: Packets sent from the router to a WAN/LAN interface. 
 
Trusted mode: Honors the domain mapping (ToS byte, WME, WLAN user priority). 
 
Untrusted mode: Does not honor domain mapping. This is the default QoS setting. 
 
Traffic Conditioning Agreement (TCA): The TCA needs to be defined for each interface: 
o  Ingress mappings (Domain =>CoS) 
o  Egress Mappings (CoS => Domain) 
o  Untrusted mode (default) 
 
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