Riverstone Networks WICT1-12 - Manual (Page 565)

Riverstone Networks RS Switch Router User Guide Release 8.0 26-3
QoS Configuration RS Queuing Policies
• IPX
- Destination network – 1
- Source network – 2
- Destination node – 3
- Source node – 4
- Destination port – 5
- Source port – 6
- Interface – 7
Use the
qos precedence ip
and
qos precedence ipx
commands to change the default precedence.
26.3 RS QUEUING POLICIES
There are two types of queuing policies you can use on the RS:
Strict priority – Assures the higher priorities of throughput but at the expense of lower priorities. For example, during
heavy loads, low-priority traffic can be dropped to preserve throughput of control-priority traffic. This is the default
queuing policy.
Weighted fair queuing – Distributes priority throughput among the four priorities based on percentages. This queuing
policy is set on a per-port basis.
26.4 TRAFFIC PRIORITIZATION FOR LAYER-2 FLOWS
QoS policies applied to Layer-2 flows allow you to assign priorities based on source and destination MAC addresses.
A QoS policy set for a Layer-2 flow allows you to classify the priority of traffic from:
• A specific source MAC address to a specific destination MAC address (use only when the port is in
flow bridging mode).
• Any source MAC address to a specific destination MAC address.
Before applying a QoS policy to a Layer-2 flow, you must first determine whether a port is in the address-bridging
mode or flow-bridging mode. If a port is operating in address-bridging mode (default), you can specify the priority
based on the destination MAC address and a VLAN ID. You can also specify a list of ports to apply the policy.
If a port is operating in the flow-bridging mode, you can be more specific and configure priorities for frames that match
both a source and a destination MAC address and a VLAN ID. You can also specify a list of ports to apply the policy.
The VLAN ID in the QoS configuration must match the VLAN ID assigned to the list of ports to which the QoS policy
is applied. In a Layer-2 only configuration, each port has only one VLAN ID associated with it and the QoS policy
should have the same VLAN ID. When different VLANs are assigned to the same port using different protocol
VLANs, the Layer-2 QoS policy must match the VLAN ID of the protocol VLAN.
Note In the flow mode, you can also ignore the source MAC address and configure the
priority based on the destination MAC address only.