Reliable packetized service Acknowledged delivery of frames Fabric cannot discard frames without notification (BSY / RJT)
Class 2—reliable packetized service: • Fibre Channel frames are returned to acknowledge receipt of frames that are sent. This communication occurs between the sending device and the receiving device.
• If the Fibre Channel fabric cannot deliver a frame for any reason it must send a frame back to the transmitting device indicating non- delivery.
• Every frame sent generally has an acknowledge frame returned. The Fibre Channel standard allows for a single frame acknowledgement for a group of frames, but this has not been implemented in current technology.