Deployment Guide

6 Dell EMC Networking – Deploying Data Center Bridging
1.3 Enhanced Transmission Selection (802.1Qaz)
The third enhancement specifies enhancement of transmission selection to support allocation of bandwidth
amongst traffic classes. When the offered load in a traffic class does not use its allocated bandwidth,
enhanced transmission selection allows other traffic classes to use the available bandwidth.
The-bandwidth allocation priorities coexist with strict priorities.
Networks prioritize traffic to provide different service characteristics to traffic classes. It is desirable to be able
to share bandwidth between priorities carrying bursts of high offered-loads rather than servicing them with
strict priority, while allowing strict priority for time-sensitive and management traffic that requires minimum
latency. Also, when traffic at one priority level does not use its allocation, it is desirable to allow other priorities
to use that bandwidth.
1.4 DCBx
The fourth enhancement is an exchange protocol. This protocol is a discovery and capability-exchange
protocol that is used for conveying capabilities and configuration of the features between neighbors to ensure
consistent configuration across the network. This protocol is expected to leverage functionality that
IEEE 802.1AB (LLDP) provides.