Choosing the right fiber cables
When purchasing fiber cables for your optical transceivers, there are many parameters to consider, which could be overwhelming to first-time buyers. Some parameters are determined easily from your requirements, such as connector type, cable length, and polarity. Others are less obvious as they often depend on your networking infrastructure or only become relevant when comparing between different types of products. In this article, we list some of the common parameters to consider when purchasing fiber cables for your optical transceivers, and explain how they are relevant to your needs.
Making a proper choice for each of the following parameters depends on the type of transceivers or network devices to be used with the fiber cable.
Connector Types (LC or MPO/MTP)
Most common types of fiber cable connectors used for optical transceivers and networks are LC and MPO/MTP.LC connectors, often in duplex (pair), are normally used for single-mode fibers and for the intermediate to long ranges.MPO/MTP connectors are used for both single-mode and multimode fibers and for short-range parallel mode uses.
See https://vitextech.com/mpo-mtp-connectors-difference/ for the differences between MPO and MTP connectors.
See https://vitextech.com/fiber-connector-types/ for more comprehensive overview of fiber connector types.
Fiber Types & Jacket Colors (Single-mode or Multimode)
Single-mode (SM) fiber cables are available in OS1 and OS2, both using 9/125um fiber. Single-mode fiber cables are identified by yellow cable jacket. Multimode (MM) fiber cables are available in OM1, OM2, OM3, and OM4. OM1 uses 62.5/125um fibers while OM2 and higher use 50/125um. OM1 & OM2 come in orange cable jacket while OM3 in aqua. OM4 may come in either aqua or purple.
Polish Type (UPC or APC)
Single-mode fiber cables used for optical transceivers are available in UPC or APC polish type. Single-mode UPC fiber cables are identified with blue connector while single-mode APC fiber cables are with green connector. Multimode fiber cables used for optical transceivers are normally with UPC polish.
Connectors with UPC polish cannot mate with APC polish, so it is important to find what polish type is used in your transceiver or network device.
Cable polarity determines the internal mapping of fibers when multiple fibers are used between connectors, such as LC duplex and MPO/MTP cables. LC duplex cables are available in Type AA (crossover) or Type AB (straight-thru) polarity while MPO/MTP cables are available in Type A, B, or C. Which polarity is needed depends on your network topology, but for most direct patch use (transceiver to transceiver), Type AB (LC duplex) or Type B (MPO/MTP) is used.
For MPO/MTP cables, female gender is be used on the transceiver side. Changing gender from female to male, or vice versa, is possible but requires special tools.
Cable Jacket Rating (LSZH, OFNR, OFNP)
The proper rating of cable jacket is determined by how and where the fiber cable is used. LSZH (Low Smoke Zero Halogen) rated cables emit little harmful smoke in case of fire, and are often the most widely available and cost-effective type of cables found. OFNR (riser) rated cables may be used behind a wall or between floors, and OFNP (plenum) rated cables may be used in plenum area to prevent spread of fire in absence of sprinkler system. Note that a higher rated cable may be used in areas that require lesser-rated ones. So, OFNP cables can be used in riser application, and OFNR cables can be used in patch panels.
In case of MPO/MTP cables, 12-fiber cables are commonly used for patching transceivers, but 16 or 24 fibers also used for 400G network transceivers.
The table below is an easy reference tool to help you choose the right fiber cables for your transceivers.
For more detailed understanding of different cable types or help with selecting proper fiber cables for your needs, please contact Vitex Sales.