IBM DS3500, Введение и руководство по внедрению

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Draft Document for Review March 28, 2011 12:24 pm
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IBM System Storage DS3500: Introduction and Implementation Guide
The name
multi-mode fiber
indicates that multiple modes, or rays of light, can travel through
the cable core simultaneously. The multi-mode fiber cable uses a larger diameter core, which
makes it easier to couple than the single-mode fibre cable. With a throughput of 8 Gbps, the
length of the cable can be up to 300 m.
Single-mode fibre
transfers a single ray of light. The core diameter is much smaller than the
core of multi-mode cable. Therefore, coupling is much more demanding and tolerances for
single-mode connectors and splices are very low. However, single-mode fiber cables can be
much longer. Cable length can exceed 50 km.
Multi-mode cabling is much more common, as it is easier to work with and meets the
requirements of most customer scenarios. However, in situations where very long cable
lengths are needed, single-mode cabling will be required.
Despite its name, Fibre Channel signaling can run on both copper wire and fiber-optic cables
as shown in Figure 1-2.
Figure 1-2 FC Cable Types
Small form-factor pluggable (SFP) transceiver
The small form-factor pluggable (SFP) or Mini-GBIC is a compact, hot-pluggable transceiver
used for both telecommunication and data communications applications. It interfaces a
network device mother board (for a switch, router, media converter or similar device) to a fiber
optic or copper networking cable. SFP transceivers are designed to support SONET, Gigabit
Ethernet, Fibre Channel, and other communications standards.
SFP transceivers are available with a variety of different transmitter and receiver types,
allowing users to select the appropriate transceiver for each link to provide the required
optical reach over the available optical fiber type (e.g. multi-mode fiber or single-mode fiber).
Optical SFP modules are commonly available in several different categories:
򐂰 850 nm 550m MMF (SX)
򐂰 1310 nm 10 km SMF (LX)