Configuration manual

Table 9. ETS Traffic Groupings
Traffic Groupings Description
Priority group A group of 802.1p priorities used for bandwidth
allocation and queue scheduling. All 802.1p priority
traffic in a group must have the same traffic
handling requirements for latency and frame loss.
Group ID A 4-bit identifier assigned to each priority group.
The range is from 0 to 7.
Group bandwidth Percentage of available bandwidth allocated to a
priority group.
Group transmission selection algorithm (TSA) Type of queue scheduling a priority group uses.
In the 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
• Bandwidth allocated by the ETS algorithm is made available after strict-priority groups are serviced. If
a priority group does not use its allocated bandwidth, the unused bandwidth is made available to
other priority groups.
• For ETS traffic selection, an algorithm is applied to priority groups using:
– Strict priority shaping
– ETS shaping
• ETS uses the DCB MIB IEEE 802.1azd2.5.
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. For
more information, refer to Link Layer Discovery Protocol (LLDP). The following LLDP TLVs are supported
for DCB parameter exchange:
PFC
parameters
PFC Configuration TLV and Application Priority Configuration TLV.
ETS parameters ETS Configuration TLV and ETS Recommendation TLV.
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Data Center Bridging (DCB)