Specifications

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McDATA Products in a SAN Environment - Planning Manual
Planning Considerations for Fibre Channel Topologies
Private devices only communicate with other devices on the same
arbitrated loop, and interconnected public and private devices
can communicate with each other. Such intermixed devices
establish operating parameters and loop topology configuration
through a port login (PLOGI) command exchange, rather than
through the switch’s name server.
Be aware that public device-to-private device communication
may cause problems. For example, it is often critical to separate
servers and storage devices with different operating systems
because accidental transfer of information from one to another
can delete or corrupt data. Plan to implement security provisions
for the switch, such as partitioning attached devices into
restricted-access groups (zoning), providing server-level access
control (persistent binding), or providing storage-level access
control. Refer to Security Provisions for additional information.
Public Versus Private
Loops
Sphereon 4000-series fabric switches support operation of public and
private loops as follows:
• Public loop - A public loop is connected to a switched fabric
through any active FL_Port. All devices attached to the loop can
communicate with each other, and public devices attached to the
loop can communicate with fabric-attached devices connected:
— Directly to another switch port configured as a fabric port
(F_Port).
— Another fabric director or switch connected to the fabric
switch through any active E_Port.
Public loop connectivity for a Sphereon 4500 Fabric Switch is
illustrated in Figure 3-5.