Information Technology Reference
In-Depth Information
FIGURE 6.16
The SC connector is an unusual-looking, square-tipped fiber-optic connector slightly cone-
shaped at the very tip. (Courtesy of Molex Fiber Optics, Inc.)
Small Form Factor (SFF) Connectors
The latest types of fiber-optic connectors are generally called small form factor (SFF)
connectors. These connectors answer the most common objection to the SC style,
namely that the SC connector cannot accommodate a two-fiber (duplex) connection
in the space of a single modular (RJ-style) jack. In addition, the design of these SFF
connectors allows two fibers to be terminated at once in a single plug or jack mod-
ule. This simplifies the installation and use of duplex fiber connections and helps
minimize polarity mistakes that come with improperly arranged fiber connectors of
other types. The SFF connectors were first authorized as part of a general “deregu-
lation” of fiber connectors in the -B revision of the TIA 568 standard, which is con-
tinued in TIA-568-C.
Specifically, TIA-568-C.3,
Optical Fiber Cabling Components Standard,
allows the use of any connector that meets general performance requirements for
fiber alignment, loss, and stability under physical loads. SFF modular style connec-
tors are not required, nor are they prohibited. In making this policy decision, the
TIA declared its intention to foster innovation and let the market decide which con-
nector style to use. Actually, the rush to non-SC RJ-style modular connectors had
already begun, so problematic was the original SC implementation. The new stan-
dard simply allows this to continue, while specifying some very strict performance
ground rules. A collection of the more popular SFF types is shown in Fig. 6.17.
