Dell PowerSwitch S4820T Configuration Guide for the S4820T System 9.112.0P1 - Page 244

Figure 28. Enhanced Transmission Selection The following table lists the traffic groupings ETS uses to select multiprotocol traffic for transmission. Table 13. ETS Traffic Groupings Traffic Groupings Group ID Group bandwidth Group transmission selection algorithm (TSA) In Dell Networking OS, ETS is implemented as follows: • ETS supports groups of 802.1p priorities that have: • PFC enabled or disabled • No bandwidth limit or no ETS processing • ETS uses the DCB MIB IEEE 802.1azd2.5. Description A 4-bit identifier assigned to each priority group. The range is from 0 to 7 configurable; 8 - 14 reservation and 15.0 - 15.7 is strict priority group.. Percentage of available bandwidth allocated to a priority group. Type of queue scheduling a priority group uses. Data Center Bridging Exchange Protocol (DCBx) DCBx allows a switch to automatically discover DCB-enabled peers and exchange configuration information. PFC and ETS use DCBx to exchange and negotiate parameters with peer devices. DCBx capabilities include: • Discovery of DCB capabilities on peer-device connections. • Determination of possible mismatch in DCB configuration on a peer link. • Configuration of a peer device over a DCB link. DCBx requires the link layer discovery protocol (LLDP) to provide the path to exchange DCB parameters with peer devices. Exchanged parameters are sent in organizationally specific TLVs in LLDP data units. The following LLDP TLVs are supported for DCB parameter exchange: PFC parameters PFC Configuration TLV and Application Priority Configuration TLV. 244 Data Center Bridging (DCB)