Seagate tv cables 77767496 Manual

PDF Manuals
432 Pages English

Seagate tv cables 77767496
Pages
OF
432
Fibre Channel Interface Manual, Rev. D 31
7.0 Classes of service (FC-2)
There are five classes of service currently available or being defined. Classes of service are simply different
communication methods used between nodes. Seagate drives use only Class 3; however, brief explanations of
the other classes are provided as well.
7.1 Class 1
Class 1 is like a direct face-to-face meeting with no interruptions or delays. It is a dedicated full-bandwidth con-
nection between two nodes.
Other Class 1 attributes
• Guaranteed delivery
• Frames are received in the order they are transmitted
• Usually uses the least overall bandwidth
• Very little software interaction
7.2 Class 2
Class 2 is like an electronic mail transaction where each message has an acknowledgment message sent from
the receiver to signal that the message was received successfully. This class of service allows one N_Port to
transmit consecutive frames to multiple destinations without establishing a dedicated connection with any spe-
cific N_Port and also allows one N_Port to receive consecutive frames from one or more N_Ports without hav-
ing established dedicated connections with any of them.
Other Class 2 attributes
• Confirmed delivery (the receiver sends an acknowledgment on receipt)
• Frames are not always guaranteed to be received in the order they are transmitted
• Can potentially use more bandwidth than Class 1 and latency may increase by waiting for acknowledgments
7.3 Class 3
Class 3 service multiplexes frames at frame boundaries to or from one or more N_Ports without acknowledg-
ment of receipt.
Seagate drives use Class 3 exclusively. Class 3 reduces the complexity of the ports and provides better perfor-
mance for disc applications.
Other Class 3 attributes
• Full duplex transfers may be used between two ports using Class 3; however, Class 3 operation does not
require half duplex operation.
• Acknowledge (ACK) buffer not required (no waiting for ACKs)
Table of Contents
Expand All
Related Manuals for Seagate tv cables 77767496
Fibre Channel Interface
Seagate tv cables Fibre Channel Interface

For tv cables (432 Pages)