Data Center Bridging - IEEE Task Group

IEEE Task Group

The following have been adopted as IEEE standards:

• Priority-based Flow Control (PFC): IEEE 802.1Qbb provides a link level flow control mechanism that can be controlled independently for each frame priority. The goal of this mechanism is to ensure zero loss under congestion in DCB networks.

• Enhanced Transmission Selection (ETS): IEEE 802.1Qaz provides a common management framework for assignment of bandwidth to frame priorities.

• Congestion Notification: IEEE 802.1Qau provides end to end congestion management for protocols that are capable of transmission rate limiting to avoid frame loss. It is expected to benefit protocols such as TCP that do have native congestion management as it reacts to congestion in a more timely manner.

• Data Center Bridging Capabilities Exchange Protocol (DCBX): a discovery and capability exchange protocol that is used for conveying capabilities and configuration of the above features between neighbors to ensure consistent configuration across the network. This protocol leverages functionality provided by IEEE 802.1AB (LLDP). It is actually included in the 802.1az standard.