Storage Area Networks For Dummies®

Chapter 2: SAN Building Blocks
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Figure 2-4:
Servers
sharing a
storage
array with a
SAN hub.
LUN 0
LUN 1
Hubs use a particular version of the Fibre Channel protocol (see the section
“Protocols used in a Fibre Channel SAN,” later in this chapter) called Fibre
Channel Arbitrated Loop, or FC-AL: The devices arbitrate for access to the
loop so they can communicate with other devices attached to the loop. The
FC-AL protocol handles that arbitration. Devices connected to a hub share
the total bandwidth of the hub.
Every port shares the loop.
Figure 2-5:
Sharing
the loop
in a hub.
Storage