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Benefits of Configuring CoS Hierarchical Port Scheduling


Hierarchical port scheduling enables you to control the amount of bandwidth allocated to different traffic classes on each port in a way that maximizes flexibility and bandwidth utilization. Hierarchical port scheduling is the Junos® operating system (Junos OS) implementation of enhanced transmission selection (ETS, described in IEEE 802.1Qaz).

ETS is part of the data center bridging (DCB) IEEE standards that provide features to support lossless transport over Ethernet networks for use in data center environments.

ETS provides the flexibility to allocate a guaranteed minimum port bandwidth to any traffic class. In addition, after meeting the minimum bandwidth guarantees, ETS dynamically shares the remaining port bandwidth among the traffic classes in accordance with your configuration. This combination of capabilities results both in bandwidth guarantees for lossless traffic and in better port bandwidth utilization, which saves you money. You can configure different hierarchical port scheduling on different interfaces to customize your bandwidth allocation and utilization.

Bandwidth guarantees ensure that lossless traffic receives the bandwidth required to prevent packet loss. Better port utilization enables you to forward the same amount of traffic on fewer links than switches that do not provide ETS hierarchical scheduling. Thus, you need fewer ports to handle network traffic, which is also cost-effective.