Ingress Traffic Concepts - Allied Telesis SwitchBlade x3100 Series Manual

Ingress Traffic Concepts

Rule A
Rule B
Rule C
Ingress
Traffic
Rule D
Rule E
Rule F
Classification Filtering/Remarking/Policing Mapping
6.2.1 Ingress Traffic Concepts
The main strategy in providing QoS is to first classify and segregate traffic into separate flows. These flows
can then be managed separately through the provider's network with each flow getting a specified level of ser-
vice. Traffic classification and segregation are performed when traffic from a customer enters the network
through the network edge device. Traffic is classified and segregated according to set of criteria or rules. Once
the traffic is classified, the packets will have certain actions performed upon them as configured by the provider.
These actions are mark, meter, count, and drop.
To mark a packet in the traffic flow means that once a packet has been allowed to ingress the port, it will be
associated with a certain flow. Marking the packet means to identify the packet with a Class of Service (COS)
that will be applied to the packet as it moves through the device and into the network.
For ethernet frames, these are defined as the 802.1p user priority bits or class of service bits.
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Software Reference for SwitchBlade x3100 Series Switches (Access and Security)
drop
mark
mark
meter
count
drop
mark
meter
drop
Model of Traffic Flow for a QoS-capable Device
FIGURE 6-1
drop
Queuing
Introduction
Egress
Traffic
Scheduling Shaping
6-3