EonStor DS S48 Series Hardware Manual
3.2.1
Fibre-Host Port
Auto speed detection
Speed auto-detection is specified by the Fibre Channel standard. If a 4Gbps port is
connected to an 8Gbps port, it will negotiate down and run at 4Gbps. If there are
8Gbps ports on both ends of the link, the link will run at 8Gbps.
SFP transceivers
The Fibre host ports use a SFP transceiver to convert electrical data signals into light
signals and transfers them transparently via optical fiber. A transceiver provides
bi-directional data links, a laser transmitter (for fiber optic cables), LC connector, and
a metal enclosure to lower the EMI.
Other beneficial features of a typical SFP transceiver include a single power supply,
low power dissipation, and hot-swap capability. It is also important that any
transceiver you use meets the FC performance and reliability specifications.
WARNING
The SFP transceiver from Infortrend contains a laser diode featuring class 1 laser. To
ensure continued safety, do not remove any covers or attempt to gain access to the
inside of the product. Refer all servicing to qualified personnel.
FC port dust plugs
Each FC port comes with a dust plug. Remove these dust plugs only when you are
ready to insert an SFP transceiver.
3.2.2
Fibre-Host Topologies
The Fibre Channel standard supports three (3) separate topologies. They are
point-to-point, Fibre Channel Arbitrated Loop (FC-AL), and fabric switch topologies.
Point-to-Point: Point-to-point topology is the simplest topology. It is a
direct connection between two (2) Fibre Channel devices.
FC-AL: This is the most common topology currently in use. Fibre
Channel devices are all connected to a loop. Each device is assigned
an arbitrated loop physical address (AL_PA). The FC-AL supports 124
devices in a single loop.
Fabric: The fabric topology supports up to 224 Fibre Channel devices.
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