100G QSFP28 transceivers have currently been highly favored by Ethernet users and been widely applied to the data centers. The QSFP28 transceivers that are supported on Ethernet network devices use fiber optic cables and connectors. The type of connector and the type of fiber depend on the transceiver type. To make sure right connectivity, it is of necessity to know the appropriate patch cable and connectors for QSFP28 transceivers. This article would introduce the cable and connector specifications and deployment as well as some precautions for QSFP28 transceivers.
12-Ribbon patch cable with MPO connectors and LC duplex patch cable are two common fiber optic patch cables connected with 100G QSFP28 transceivers to achieve 100G Ethernet network connectivity. A 12-fiber ribbon cable can be used in outside plant applications or inside buildings when covered with flame-retardant outer jackets. LC duplex patch cable uses for specific 100G transceivers, such as 100GBASE LR4, 100GBASE CWDM4 and etc. The 100GBASE SR4 transceiver supports maximum data links up to 100 m through MTP-12 patch cables. By using LC duplex patch cable, the transmission distance of 100GBASE-LR4 can arrive 10 km.
You can use 12-Ribbon Patch cable with MPO connectors to connect two transceivers of the same type—for example, 100GBASE-SR4-to-100GBASE-SR4 or 100GBASE-PSM4-to-100GBASE-PSM4. That is to say, you can choose a MTP trunk cable together with the 100GBASE-SR4 QSFP28 module for direct 100G connection. The following picture shows two 100GBASE-SR4 QSFP+ transceivers connected by a multimode 12-fiber MTP trunk cable.
As we mentioned above, you can also use SMF patch cables with LC duplex connectors to connect two supported transceivers of the same type—for example, 40GBASE-LR4-to-40GBASE-LR4 or 100GBASE-LR4-to-100GBASE-LR4. The SMF patch cable is one fiber pair with two LC duplex connectors at opposite ends. You can simply plug the LC duplex connectors into the corresponding duplex ports of 100GBASE-LR4, 100GBASE-CWDM4 and etc. 100G direct connection is just achieved by LC duplex patch cable connected with two same 100GBASE-LR4 transceivers, presented in the below figure.
1.Ensure that you order cables with correct polarity. The multifiber push-on (MPO) connectors on the 12-ribbon cables must be key-up (sometimes referred to as latch up, Type B, or Method B). If you are using patch panels between two QSFP28 transceivers, ensure that the proper polarity is maintained through the cable plant.
2. Ensure that the fiber end in the connector is finished correctly. Physical contact (PC) refers to fiber that has been polished flat. Angled physical contact (APC) refers to fiber that has been polished at an angle.
3. Caution: Use only a properly constructed, shield cable to ensure correct connectivity.
100G QSFP28 modules is an inevitable choice for Ethernet connectivity with a purpose to suit the future Ethernet network upgrading and higher bandwidth. 12-fiber MTP patch cable and LC duplex patch cable are used for connecting different 100G transceivers with different ports respectively. Moreover, there are something you need to keep in mind in case of causing unnecessary losses and incidents.