Tag Archives: MTP trunk cable

MTP Solutions for High-Density Needs

With the ever-increasing demands for high-density backbone cabling. MTP solutions have enjoyed widespread popularity. In this post, we will have an exploration of two MTP solutions: MTP cable and MTP cassette. For those who are unfamiliar with this term, it’s necessary for us to get started from its basics.

Background Information on MTP

In this part, you are required to acquire three terms: MTP, MPO, and polarity.

MPO

MPO stands for “multi-fiber push on” connector. Usually, it refers to a type of a multiple fiber core connector, defined by IEC-61754-7 (common standard) and the U.S. TIA-604-5 Standard.

MTP

MTP is the short for “multi-fiber termination push-on” connector, which is the latest generation of MPO connector developed by US Conec. Fully compliant with the MPO standards, the multi-fiber termination push-on connector is considered as MPO fiber connector. For multi-fiber termination push-on or multi-fiber push on connector, they can both accommodate 8 to 24 fibers, which are the perfect choices for the 40G/100G network. Multi-fiber termination push-on or multi-fiber push on connector is available in a female version (without pins), or a male version (with pins) as shown in figure 1. The pins ensure the exact alignment of the fronts of the connectors, which protects the interfaces of the connectors from being offset.

MTP Connectors

Figure 1: MTP Connectors

Also, there are guide grooves (keys) on the top side of the factory terminated multi-fiber termination push-on connectors, which ensure that the adapter holds the connector with the correct ends aligned with each other. According to the key, the multi-fiber termination push-on connector comes with two types. One is “key-up to key-down”, which means the key is up on the one side and down on the other. The two connectors are connected turned 180°in relation to each other. The other one is “key-up to key-up”, which means both keys are up. The two connectors are connected while in the same position in relation to each other.

MTP Connector Structure

Figure 2:  Multi-fiber Termination Push-on Connector Structure

Polarity

In any installation, it is important to ensure that the optical transmitter at one end is connected to the optical receiver at the other. This matching of the transmitting signal (Tx) to the receiving equipment (Rx) at both ends of the fiber optic link is referred to as polarity.

MTP Solutions

For multi-fiber termination push-on solutions, there are two frequently used applications: MTP cable and multi-fiber termination push-on cassettes. They are the best choices for providing a simple, cost-effective, and structured cabling system.

MTP Solutions

Figure 3: MTP Solutions

Cables

Multi-fiber termination push-on cables usually consist of the multi-fiber termination push-on connectors and the fiber optic cables. Sometimes, the LC connectors are used, which we will expound in the following part. As for fiber cables, they are typically used in OS2, OM3 or OM4. With different applications, the multi-fiber termination push-on cable can be classified into multi-fiber termination push-on trunk cable and multi-fiber termination push-on harness cable.

Trunk Cable

Serving as a permanent link, the trunk cable is designed to connect multi-fiber termination push-on or multi-fiber push on modules to each other. It’s available in 12, 24, 48 and 72 fibers. For the ends, the cable is commonly found to be terminated with 12-fiber or 24-fiber multi-fiber termination push-on or multi-fiber push on connectors. When it comes with the polarity of the patch cord, there are three different types (type A, B, and C), which is defined in the TIA standard. In the following figures, the three different connectivity methods for 12-fiber and 24-fiber MTP/MPO trunk cable are showed respectively.

12-Fiber MTP Trunk Cable

Figure 4: 12-Fiber Multi-fiber Termination Push-on Trunk Cable

24-Fiber MTP Trunk Cable

Figure 5: 24-Fiber Multi-fiber Termination Push-on Trunk Cable

Harness Cable

Multi-fiber termination push-on harness cable is used to provide a transition from multifiber cables to individual fibers or duplex connectors. For instance, 8 fibers 12 strands MTP-LC breakout cable has eight LC fiber connectors and a multi-fiber termination push-on connector. According to data of FS.COM, the 8-fiber and 24-fiber MTP to LC breakout cables are the best-selling multi-fiber termination push-on connector harness cables. For the polarity, the 8-fiber multi-fiber termination push-on connector breakout patch cord has two types (Type A and Type B); while the 24-fiber harness cable has three types (Type A, Type B, and Type C). For details, please refer to the following figures.

12-Fiber MTP Harness Cable

Figure 6: 12-Fiber Multi-fiber Termination Push-on Harness Cable

24-Fiber MTP Harness Cable

Figure 7: 24-Fiber Multi-fiber Termination Push-on Harness Cable

 Cassette

MTP-cassette is a kind of pre-terminated cassette module. It enables the “transition” from ribbon cables terminated with multi-fiber termination push-on connector connectors to the LC or SC interface on the transceiver terminal equipment. Conventionally, the multi-fiber termination push-on connector cassette is loaded with 8, 12 or 24 fibers and have LC or SC adapters on the front side and multi-fiber termination push-on connector at the rear. Nowadays, the three most widely used cassettes are MTP-8, MTP-12, and MTP-24 cassettes, or also known as Base-8, Base-12, and Base-24 multi-fiber termination push-on cassettes. For MTP-8 cassette, it is only available in Type A. While multi-fiber termination push-on-12 and multi-fiber termination push-on-24 cassettes both come with Type A and Type AF. For their polarity details, please refer to the following figures.

MTP-8 Cassette

Figure 8: Multi-fiber Termination Push-on-8 Cassette

MTP-12 Cassette

Figure 9:  Multi-fiber Termination Push-on-12 Cassette

MTP-24 Cassette

Figure 10:  Multi-fiber Termination Push-on-24 Cassette

Summary

In this post, we make an overview of MTP, including what the multi-fiber termination push-on and multi-fiber push on, and what their the polarities are. Then we share three types of multi-fiber termination push-on solutions for high-density networking: MTP trunk cable, MTP harness cable, and MTP cassette.

12-Fiber MTP Cabling System

MTP fiber cables and related components are now widely deployed in high speed fiber optic transmission system. MTP cables really provide great performance during 40G and 100G transmission over both short and long transmission distances. But there are so many types of MTP components like MTP cables, MTP cassettes, MTP adapters, MTP patch panels, etc. And all of these products are available in different MTP polarity types. Customers can get confused easily by these MTP products.

12-fiber MTP trunk cable

In addition, unlike traditional duplex transmission on two fibers or BiDi transmission over a single fiber, MTP system transmits optical signal over 12, 24 or more fibers at the same time. More fibers and cables are employed in MTP cabling system. Thus, technicians in data center or server room are still facing a headache problem which is MTP cable management. This post is to offer the details of a commonly used MTP cabling system—12-fiber MTP cable system for better understanding, selecting and management of MTP products.

12-Fiber MTP Cabling Applications

The 12-fiber MTP cabling system is usually used in the following standards: 40GBASE-SR4, 40GBASE-PLRL4, and 40GBASE-PLR4. 40GBASE-SR4 is used for 40G transmission in short distances up to 150 meters over OM4 fibers. 40GBASE-PLRL4 and 40GBASE-PLR4 support transmission distance over single-mode fiber up to 1.4km and 10km separately. These standards use 40G parallel transceivers with 12-fiber MTP interfaces.

40G-SR4-QSFP+

Except 40G transceivers with 12-fiber MTP interfaces, there is a wide range of 12-fiber MTP connectivity components for transmission. These MTP cabling products cable be used in a lot of applications.

12-Fiber MTP Cabling Connectivity Components

12-Fiber MTP Trunk Cable: MTP trunk cable can be regarded as MTP to MTP fiber patch cable. MTP trunk cable is terminated with MTP connectors on both ends. The MTP connectors can be male (with guide pin on the contact interface) or female (without guide pin). As above mentioned, MTP cables can be divided into different types: Polarity A, Polarity B and Polarity C. A previous of my article “Understanding Polarity in MPO System” has introduced the polarity of MTP components. You can follow this article about the MTP polarity details.

The most commonly used MTP trunk cable is a single strand of cable, which can provide duplex 40G transmission at the same time. There are also MTP trunk cables which are composed by several strands of cables. Take the example of 12-fiber MTP trunk cables as shown in the following picture. On the left of this picture, there is a 12-fiber MTP trunk cable which is a single strand cable. On the right of this picture, there is a 72-fiber MTP trunk cable which is composed by 6 strands of 12-fiber MTP trunk cable.

12-fiber MTP trunk cable

12-Fiber MTP Harness Cable: MTP harness cable is a length of fanout cable with one end terminated with MTP connector and the other end terminated with several connectors like LC and SC. 12-fiber MTP harness cables also come in a variety of types according to fiber type, polarity type and connector types. The following picture shows a most commonly used MTP-4 duplex LC fiber cable.

MTP-8LC harness fiber cable

12-Fiber MTP Cassette: MTP cassette is like MTP harness cable which also provides the transferring between MTP interface and LC or SC interfaces. But MTP cassette can protect the fragile optical fibers inside the metal box, and has lower space requirements than MTP harness cable. The following picture shows a 12-fiber MTP-LC Cassette.

12-FIber MTP-LC Cassette

Typical 12-Fiber MTP Cabling Guide

The 12-Fiber MTP fiber optic products can be used in many situations not only for 40G fiber network. The following introduces several typical fiber cabling solutions using 12-fiber MTP products.

12-Fiber MTP Products in 10G to 10G Transmission

The following picture shows the wire guide for 10G to 10G connections using OM3 12-fiber MTP fiber cables and 12-fiber MTP-LC cassettes. A 10G link just uses two of the 12 fibers. On each end of this link, up to six 10GBASE-SR SFP+ modules can be connected to the fiber optic network, which means up to 60G can be transmitted by the following 12-fiber MTP system.

10G MTP fiber cabling

12-Fiber MTP Products in 40G to 40G Transmission

For 40G to 40G transmission, MTP trunk cable is usually being used. The following picture shows the connection of two brocade ICX 7750 switches over long transmission distance. Brocade compatible QSFP-PLR4-40G transceivers are being used on both ends of this 40G fiber link. 12-fiber MTP OS2 trunk cable is being used to connect the QSFP+ modules on each end.

40G-QSFP-PLR4 Cabling

    Items required in this 40G to 40G fiber optic link

  • QSFP-PLR4-40G QSFP+
  • OS2 12-Fiber MTP Trunk Cable

12-Fiber MTP products in 40G to 10G Transmission

Sometime the 40G device is still required to be connected with 10G devices. Here takes the example of connection between 40G QSFP+ port on Brocade 7750 and 10G SFP+ port on Brocade Fastlron FCX6245 over long transmission distances. To distribute the 40G signals into four 10G, Brocade compatible QSFP-PLR4-40G transceiver, and Brocade compatible 10G-LR SFP+ transceiver, 12-fiber MTP-LC cassette, 12-fiber MTP trunk cable and four LC-LC duplex single-mode fiber patch cables are used. The MTP cassette transmitting the MTP interface to the LC interfaces as shown in the following picture.

40G-PLR4 cabling

    Items required in this 40G to 10G fiber optic link

  • QSFP-PLR4-40G QSFP+
  • OS2 12-Fiber MTP Trunk Cable
  • OS2 12-Fiber MTP-LC Cassette
  • OS2 LC-LC Fiber Patch Cable
  • 10G-LR SFP+
Conclusion

12-fiber MTP cabling system is a cost-effective and space saving solution for both 10G and 40G transmission. As most of the MTP fiber products are factory pre-terminated, these products can provide fast installation and great network performance. FS.COM provides full range of MTP fiber optic products. You can visit FS.COM or contact sales@fs.com for more details about MTP fiber cabling.