Tag Archives: MTP cable

8-Fiber MTP VS. 12-Fiber MTP Cables

MTP fiber cable in data center becomes increasingly popular in data center with the wide deployment of 40G and 100G network. It is common that 40G and 100G network usually based on 12-fiber MTP networking system. However, not all the 12 fibers of MTP cable are used.8-fiber MTP cable

12-Fiber MTP Cable During Transmission

There are usually 4 fibers left unused, if you are using a 12-fiber MTP cable to transmit 40G with QSFP+ module or 100G with QSFP28 module. The following shows how 12-fiber MTP fiber cable works when it is used to be connected with 40Gbase-SR4 QSFP+ module. If more 12-fiber MTP cables are used, more optical fibers will be wasted. As IEEE standards like 40GBASE-SR4 and 40GBASE-SR10 uses only 8 fibers for dual-way transmission, manufacturers provide new versions of MTP fiber cable which contains only 8 optical fibers but still used the standard MTP interfaces.40gbase-sr4

Base-8 MTP for Higher Density and Lower Utilization

Network built with 8-fiber MTP system can transmit the same data with less cost and higher density compared with 12-fiber MTP system. All fiber will be 100% utilized in base-8 MTP products. It could be a cost-effect solution for both 40G to 40G transmission and 40G to 10G transmission. 8-fiber MTP trunk cables and 8-fiber MTP-LC harness cable are already provided in the market. There are also rack designed 8-Fiber MTP breakout panels for 40G to 10G applications.

MTP-LC-harness-cable MTP-LC-harness-cable
MTP-LC Harness Cable MTP-LC 40/100G Breakout Panel

Convert 12-Fiber MTP to 8-Fiber MTP Cabling System

However, most MTP cabling systems are based on 12-fiber or 24-fiber MTP system, especially for backbone cabling. MTP conversion cables are provided in the market which offer conversion between 12/24-fiber MTP and 8-fiber MTP cabling systems. The following shows two types of 8-fiber MTP conversion cables which can provide 12-fiber to 8-fiber MTP conversion and 24-fiber to 8-fiber MTP conversion separately.

24 to 8 fiber MTP conversion cable 12 to 8 fiber MTP conversion cable
1*3 MTP Conversion Cable 2*3 MTP Conversion Cable

If you have already deployed 12-fiber MTP cabling system in your data center, 2*3 MTP conversion cable is suggested to be used. With one end terminated with two 12-fiber MTP cable and the other end terminated with three 8-fiber MTP connectors, 12-fiber to 8-fiber MTP cabling conversion could be achieved, as well as 100% optical fiber utilization in 12-fiber MTP system.

1*3 MTP conversion cable has a 24-fiber MTP cable on one end and three 8-fiber MTP cable on the other end. With this cable, a length of 24-fiber MTP cable can provide three ways of 40G signal dual-way transmission. All the fibers in a 24-fiber cabling system cable be used.

Conclusion

It is clear that the 8-fiber, 12-fiber based and 2-fiber based cabling system will exist for a long term in 40/100G network. 8-fiber MTP cabling system can provide higher optical fiber utilization with lower cost and higher cabling density. If you want to transfer 12-fiber MTP system to 8-fiber MTP system, you can use MTP conversion cables. 8-base MTP system, could be regarded as an additional option for the existing fiber network infrastructure.

How to Connect 40G QSFP+ SR4 Transceivers to Network

40G network is gradually being applied in today’s backbone transmission network, during which long distance transmission is required. 40G QSFP+ SR4 fiber optic transceiver is being widely applied for 40G transmission in short distances. Generally, 40G QSFP+ SR4, working on wavelength of 850 nm, can support 40G fiber optic transmission a distance up to 150 m over OM4 multimode optical fiber. Inserted in switch, QSFP+ SR4 module utilizes a MTP/MPO interface for dual way transmission. There are a lot of methods to connect QSFP+ SR4 transceivers with other devices for different applications, by using different connectivity products. In addition, the cabling for 40G is relatively more difficult than that of 10G network, which requires more cables and spaces. The following will introduce several high density QSFP+ SR4 transceiver cabling methods.

QSFP+ SR4 40G to 40G Applications

40G to 40G transmission is needed in a 40G fiber optic network. The following picture simply illustrates how 40G to 40G multimode transmission is being achieved by QSFP+ SR4 transceivers. Two QSFP+ SR4 modules are separately inserted in two 40G switches. Then the two transceiver are connected by a length of multimode MTP trunk cable. This is the simplest way to use QSFP+ SR4 transceiver.

40G cabling

In some cases, there are lot of 40G connections required at the same time and same places, which means the increasing of both cable count and cabling difficulty. For better cable management and higher density cabling, a 48-port 1U rack mount MTP fiber patch enclosure can be used as shown in the following picture. Up to four 12-port MTP fiber adapter panels can be deployed in this standard 1U rack mount enclosure. With the help of this 48-port MTP fiber enclosure, cable management for 40G connections could be easier.

40G to 40G cabling

QSFP+ SR4 40G to 10G Applications

QSFP+ SR4 is a parallel fiber optic transceiver which means it uses four fibers for transmitting and four fibers for receiving at the same time. The 40G fiber optic signal can be separated into four 10G signals to meet the 40G to 10G transferring requirements. The fiber optic cable count will be increased at the 10G distribution end. Usually a breakout MTP-8LC harness cable is used. For better cable management, a 1U 96-fiber enclosure is recommended, which includes four HD MTP cassettes transferring MTP front the 40G end to LC at the 10G end. Four 10G-SR SFP+ modules, inserted in 10G switch/ports, can be connected to the corresponding LC ports on this fiber enclosure to achieve the duplex transmission between 40G and 10G.

40G to 10G cabling

For higher cabling density, the above mentioned 48-port 1U rack mount MTP fiber patch enclosure is still being recommended, which can provide high density 40G MTP cabling environment. And additional MTP-8LC harness cables should be used for transferring signals between 40G and 10G (shown in the following picture).

40G to 10G high density cabling

Conclusion

Depending on its parallel transmission mode, QSFP+ SR4 modules can meet a variety of cabling applications with great flexibility. The above methods is just several commonly used ones, detailed cabling methods for QSFP+ SR4 modules are depended on the practical applications and cabling environments. Related products for the above mentioned methods are listed in the following tables. Kindly visit FS.COM or click the attached links for more details. You can also contact sales@fs.com for more information about 40G cabling.

Products Description
40G QSFP+ SR4 Module 40GBASE-SR4 QSFP+ 850nm 150m MTP/MPO DOM Transceiver
10G-SR SFP+ Module 10GBASE-SR SFP+, 850nm 300m, MMF, LC duplex
MTP Trunk Cable 12 Fibers OM4, 12 Strands MTP Female to Female, Polarity Type B
MTP-LC Harness Cable 8 Fibers OM4, 12 Strands MTP Harness Cable, Polarity Type B
LC-LC Fiber Patch Cable 1~100M LC-LC Duplex 10G OM4, MMF Fiber Patch Cable
96 Fibers Rackmount Fiber Enclosure 96 Fibers 1U Rackmount Fiber Enclosure loaded with 4 MTP HD Cassettes 2x MTP-12 to Duplex LC/UPC 10G OM4
48 Ports MTP Fiber Enclosure 1U Rackmount FHD Series Fiber Enclosure, Loaded with 4 FAPs (12xMTP)