Tag Archives: MTP/MPO

The Era of Fusion Splicing Is Coming


Fusion splicingAs fiber deployment has become mainstream, splicing has naturally crossed from the outside plant (OSP) world into the enterprise and even the data center environment. Fusion splicing involves the use of localized heat to melt together or fuse the ends of two optical fibers. The preparation process involves removing the protective coating from each fiber, precise cleaving, and inspection of the fiber end-faces. Fusion splicing has been around for several decades, and it’s a trusted method for permanently fusing together the ends of two optical fibers to realize a specific length or to repair a broken fiber link. However, due to the high costs of fusion splicers, it has not been actively used by many people. But these years some improvements in optical technology have been changing this status. Besides, the continued demand for increased bandwidth also spread the application of fusion splicing.

New Price of Fusion Splicers
Fusion splicers costs have been one of the biggest obstacles to a broad adoption of fusion splicing. In recent years, significant decreases in splicer prices has accelerated the popularity of fusion splicing. Today’s fusion splicers range in cost from $7,000 to $40,000. The highest-priced units are designed for specialty optical fibers, such as polarization-maintaining fibers used in the production of high-end non-electrical sensors. The lower-end fusion splicers, in the $7,000 to $10,000 range, are primarily single-fiber fixed V-groove type devices. The popular core alignment splicers range between $17,000 and $19,000, well below the $30,000 price of 20 years ago. The prices have dropped dramatically due to more efficient manufacturing, and volume is up because fiber is no longer a voodoo science and more people are working in that arena. Recently, more and more fiber being deployed closer to the customer premise with higher splice-loss budgets, which results in a greater participation of customers who are purchasing lower-end splicers to accomplish their jobs.

More Cost-effective Cable Solutions
The first and primary use of splicing in the telecommunications industry is to link fibers together in underground or aerial outside-plant fiber installations. It used to be very common to do fusion splicing at the building entrance to transition from outdoor-rated to indoor-rated cable, because the NEC (National Electrical Code) specifies that outdoor-rated cable can only come 50 feet into a building due to its flame rating. The advent of plenum-rated indoor/outdoor cable has driven that transition splicing to a minimum. But that’s not to say that fusion splicing in the premise isn’t going on.

Longer distances in the outside plant could mean that sticking with standard outdoor-rated cable and fusion splicing at the building entrance could be the more economical choice. If it’s a short run between building A and B, it makes sense to use newer indoor/outdoor cable and come right into the crossconnect. However, because indoor/outdoor cables are generally more expensive, if it’s a longer run with lower fiber counts between buildings, it could ultimately be cheaper to buy outdoor-rated cable and fusion splice to transition to indoor-rated cable, even with the additional cost of splice materials and housing.

As fiber to the home (FTTH) applications continue to grow around the globe, it is another situation that may call for fusion splicing. If you want to achieve longer distance in a FTTH application, you have to either fusion splice or do an interconnect. However, an interconnect can introduce 0.75dB of loss while the fusion splice is typically less than 0.02dB. Therefore, the easiest way to minimize the amount of loss on a FTTH circuit is to bring the individual fibers from each workstation back to the closet and then splice to a higher-fiber-count cable. This approach also enables centralizing electronics for more efficient port utilization. In FTTH applications, fusion splicing is now being used to install connectors for customer drop cables using new splice-on connector technology and drop cable fusion splicer.

FTTH drop cable fusion splicer

A Popular Option for Data Centers
A significant increase in the number of applications supported by data centers has resulted in more cables and connections than ever, making available space a foremost concern. As a result, higher-density solutions like MTP/MPO connectors and multi-fiber cables that take up less pathway space than running individual duplex cables become more popular.

Since few manufacturers offer field-installable MTP/MPO connectors, many data center managers are selecting either multi-fiber trunk cables with MTP/MPOs factory-terminated on each end, or fusion splicing to pre-terminated MTP/MPO or multi-fiber LC pigtails. When you select trunk cables with connectors on each end, data center managers often specify lengths a little bit longer because they can’t always predict exact distances between equipment and they don’t want to be short. However, they then have to deal with excess slack. When there are thousands of connections, that slack can create a lot of congestion and limit proper air flow and cooling. One alternative is to purchase a multi-fiber pigtail and then splice to a multi-fiber cable.

Inside the data center and in the enterprise LAN, 12-fiber MPO connectors provide a convenient method to support higher 40G and 100G bandwidth. Instead of fusing one fiber at a time, another type of fusion splicing which is called ribbon/mass fusion splicing is used. Ribbon/mass fusion splicing can fuse up to all 12 fibers in one ribbon at once, which offers the opportunity to significantly reduce termination labor by up to 75% with only a modest increase in tooling cost. Many of today’s cables with high fiber count involve subunits of 12 fibers each that can be quickly ribbonized. Splicing those fibers individually is very time consuming, however, ribbon/mass fusion splicers splice entire ribbons simultaneously. Ribbon/mass fusion splicer technology has been around for decades and now is available in handheld models.

Ribbon/Mass Fusion Splicer

Fusion splicing provides permanent low-loss connections that are performed quickly and easily, which are definite advantages over competing technologies. In addition, current fusion splicers are designed to provide enhanced features and high-quality performance, and be very affordable at the same time. Fiberstore provides various types and uses of fusion splicers with high quality and low price. For more information, please feel free to contact us at sales@fs.com.

Original article source: http://www.fs.com/blog/the-era-of-fusion-splicing-is-coming.html

Fiber Transmissions at Higher-speed Ethernet


When moving to 40/100GbE, the most important difference in backbone and horizontal multimode applications is the number of fiber strands. 40GBASE-SR4 uses 4 strands to transmit and receive for a total of 8 strands. 100GBASE-SR10 uses 10 lanes to transmit and receive for a total of 20 strands. SMF remains a 2-strand application and although the fiber is less expensive, SMF optics and electronics can be 10x more expensive. In data centers and backbones, it may be possible to have 8 or 20 individual strands of fiber. However, those strands may take disparate paths from one end to the other and this can cause delay skew (known as bit skew) resulting in bit errors. For this reason, the 40/100GbE standards are written around fiber optic trunk assemblies that utilize a MPO or MTP multi-fiber array connector. In these assemblies, all strands are the same length. Also referred to as “parallel optics,” this construction minimizes bit/delay skew, allowing the receive modules to receive each fibers information at virtually the same time.

MPO (Multi-fiber push-on) and MTP (Mechanical Transfer Push-on) are available in both 12 and 24 strand termination configurations used at the end of a trunk assembly. The MTP design is an improved version of the MPO. The patented MTP connector is a ruggedized version with elliptical shaped, stainless steel alignment pin tips to improve insertion guidance and reduce guide hole wear. The MTP connector also provides a ferrule float to improve mechanical performance by maintaining physical contact while under an applied load. MPO MTP trunks also support for the 10GBASE-SR/SX applications although only two fiber strands are used. In this case trunks are connected to cassettes and/or hydra assemblies, which break out the multiple fibers into two-strand connections (typically LC or SC).

MPO Cabling

The second difference in high-speed fiber configurations is polarity. For 2-strand applications such as 10GbE transmission, managing polarity is as simple as reversing the strands somewhere over the channel. This is true if the channel is constructed of individual strands or is part of a trunk assembly. In trunk assemblies, which have historically been 12-strand, there are three suggested polarity methods in the standards (as shown in the following table).

As shown above, 2-strand application polarity managing is relatively easy. When migrating from 2-strand to multi-strand parallel optics, it is important to note which polarity method was selected to assure that the correct assemblies are purchased for higher speeds. All polarity methods can be converted from 2-strand to 12-strand applications.


It is important to note that these polarity methods are suggested in the standards, not mandated. However, the mandate does state that a polarity method should be established and maintained throughout all fiber channels, mapping the transmit strand from one end to the receive strand at the other. This does not change for higher fiber count transmissions, with the exception that more strands are involved. To better visualize the transmission for multistrand applications, consider the following diagrams:

40GBASE-SR uses 8 strands of a 12-strand MPO/MTP trunk cable, (4 to transmit and 4 to receive). The middle 4 strands in the MPO/MTP connector remain dark. The interface on equipment will accept an MPO/MTP array connector rather than a traditional LC.

100GbE has three approved methods for transmission including one 24-strand (shown left) or two 12-strand trunks either “over and under” or “side-by-side” (shown right- Side-by-side configuration is not shown). The transmission uses 10 strands to transmit and 10 to receive leaving the outer unused strands dark. It is also possible to connect two 1- strand trunks via a “Y” assembly that converts two 12-strand trunk assemblies to one 24-strand assembly. Polarity must also be considered regardless of the method chosen and supported by the electronics.

The new MTP cables can bridge legacy 1Gbps/10Gbps networks over to 40Gbps/100Gbps networks, and can act as the trunk line on a network backbone. Since a single fiber cable can connect up to 24 devices, fewer cables are needed, cutting down on installation labor. The high-density, small form factor also saves space and improves air flow. With its push-pull release mechanism, the MTP connector is easy to engage and disengage.

FiberStore provide a wide range of MTP/MPO products including single mode or multimode MPO and MTP fiber cable. High density MTP/MPO trunk cables with up to 144 fibers in a single cable. Fiberstore also offer wide range of MTP MPO cassette. The standard cassettes can accommodate 12 and 24 port configurations. Different sizes of cassettes are available. Available in all fibermodes and connector options. Custom Options available including MPO MTP taps and MTP/MPO Silitter combinations.