标签归档:multimode fiber

Tips on Buying Fiber Optic Cables

Buying fiber optic cables has been a daily thing in our life. Since the field of fiber optic network is still unfamiliar to most people, not to say the detailed information about the fiber optic cable. In this article, we are going to provide some tips for you to buy fiber optic cables. Before that, let’s go over the background information of the fiber optic cable for your better understanding.

What Is the Fiber Optic Cable

The fiber optic cable refers to a kind of telecommunication cable, containing one or more glass or plastic made optic fibers, usually slightly wider than a human hair. It can carry light to transmit data. Designed for long distance transmission from hundreds of miles to thousands of miles, the fiber optic cable is an ideal choice for networking, telecommunications and storage applications in wiring closets, distribution frames, gateways, central offices and data centers.

Types of Fiber Optic Cables

According to different standards or features, there are different types of fiber optic cables. Basically, based on different transmission modes, the fiber optic cable can be grouped into two types: single mode fiber and multimode fiber.

Single Mode Fiber

The fiber optic cable for this type is a single strand of glass fiber with a diameter of 8.3 to 10 microns, which is narrower than the multimode fiber. Under such a condition, the beam of light is transmitted in a much tighter space with a higher transmission rate. Therefore, it makes the long-distance communication, sometimes as far as between continents more available.

Figure 1: Single Mode Bend Insensitive Fiber Optic Cable

Figure 1: Single Mode Bend Insensitive Fiber Optic Cable

Multimode Fiber

Compared with single mode fibers, the multimode fiber has a larger diameter (62.5µm or 50µm), allowing more space to generate and collect light. Considering about multimode fibers’ transmission performance, it is mostly used for communications over short distances no longer than 2000 m, such as within a building or in a small campus.

 Figure 2: OM1 Multimode Fiber Optic Cable

Figure 2: OM1 Multimode Fiber Optic Cable

Tips on Buying Fiber Optic Cables

After an overview of fiber optic cables, it’s time for us to learn how to buy fiber optic cables. There are some major steps offered to follow with.

Firstly, preparation. For anyone buying fiber optic cables, they need to have a full preparation. On the one hand, you need to know your network environment, such as the required transmission speed, distance etc. On the other hand, you need to have a basic understanding of the features of all kinds of optic cables. As we mentioned above, there are many types of fiber optic cables available in the market not only just based on different transmission modes, for example, according to different connectors, there are LC fiber, SC fiber, etc. Therefore, you need to know which type suits your network environment.

Next, you need to have a budget for buying optic cables in your mind. There are so many fiber optic cable suppliers in the online market, almost every supplier will offer a different fiber optic cable price. After that, you can begin your online searching. When you browse the product, you can make a comparison of the fiber optic cable price per meter among different suppliers. Besides, you have to check the suppliers’ reputation making sure their service and products are reliable.

Last, but not least. Some buyers buying fiber optic cables for their company need to consider more carefully for their complicate requirements. You had better buy your cables from suppliers who are also manufacturers, such as FS.COM, one of the top fiber optic cable manufacturers. Their service will be more mature, reliable and professional, especially for their after-sale service.

Conclusion

Buying fiber optic cable is not so difficult as you have thought. After reading this article, we believe things will be different for you.

How Much Do You Know About Multimode Fiber Optic Cables

If the multimode fiber is mentioned, most of you may be familiar with this term. As a significant member of the large fiber optic cable family, multimode fiber optic cable also consists of many sub-branches. However, not all the people are clear about these subbranches. Therefore, in this article, we will introduce the multimode fiber optic cable and its subbranches to you.

What Are Multimode Fiber Optic Cables

In optical fiber technology, the multimode fiber is a kind of optical fiber that is designed to carry multiple light rays or modes concurrently, each at a slightly different reflection angle within the optical fiber core, typically 50 or 62.5 μm for its core diameter. Mostly, the multimode fiber is used for communications over short distances, such as within a building or on a campus for the reason that its modes tend to disperse over longer lengths (this is called modal dispersion).

Applications of Multimode Fiber

Typical multimode transmission speed and distance limits are 100 Mbit/s for distances up to 2 km (100BASE-FX), 1 Gbit/s up to 1000 m, and 10 Gbit/s up to 550 m. In addition, the equipment used for communications over multimode optical fiber is less expensive than that for single-mode optical fiber. Because of its high capacity, reliability, and cheap price, the multimode optical fiber mostly is used for backbone applications in buildings, aerospace and LAN network, storage area networks.

Types of Multimode Fiber

Identified by ISO 11801 standard, multimode fiber optic cables can be classified into the OM1, OM2, OM3, OM4, and OM5 fiber. Specified by that Standard, “OM” is abbreviated for optical multimode. These five types will be presented in the following parts.

OM1 Fiber

Wearing an orange jacket, OM1 fiber cable possess a core size of 62.5 µm, supporting 10 Gigabit Ethernet at lengths of up to 33 meters. It is most commonly used for 10/100 Megabit Ethernet applications. This type is commonly used as an LED light source.

OM2 Fiber

Just like OM1, OM2 fiber also comes with an orange jacket and uses an LED light source. But, its core size is 50 µm, supporting up to 10 Gigabit Ethernet at lengths up to 82 meters and more commonly used for 1 Gigabit Ethernet applications.

Figure 1: OM2 Fiber
OM3 Fiber

Like OM2, the OM3 fiber cable’s core size is 50 µm, but it wears an aqua jacket and is optimized for laser-based equipment. OM3 supports 10 Gigabit Ethernet at lengths up to 300 meters. Besides, OM3 is able to support 40 Gigabit and 100 Gigabit Ethernet up to 100 meters. However, 10 Gigabit Ethernet is most commonly used.

Figure 2: OM3 Fiber
OM4 Fiber

Being backward compatible with OM3 fiber, the OM4 fiber shares the same aqua jacket with it. The OM4 was developed specifically for VSCEL laser transmission and allows 10 Gig/s link distances of up to 550m compared to 300M with OM3. And it’s able to run at 40/100GB up to 150 meters utilizing an MPO connector.

Figure3: OM4 Fiber
OM5 Fiber

 

OM5 fiber, also known as WBMMF (wideband multimode fiber), is the newest type of multimode fiber, and it is backward compatible with OM4. It has the same core size as OM2, OM3, and OM4. The color of the OM5 fiber jacket was lime green. It is designed and specified to support at least four WDM channels at a minimum speed of 28Gbps per channel through the 850-953 nm window.

Figure 4: OM5 Fiber

Conclusion

Through this article, we will have a basic idea of what the multimode fiber cable is and how many types it has. In general, multimode fiber cable continues to be the most cost-effective choice for enterprise and data center applications up to the 500-600 meter range. However, since the fiber patch cable is a very large family, every kind has its own features. Before making a choice, the key point is we need to understand whether our demands match the patch cable we want to choose.

Comparison of OM1, OM2, OM3 & OM4 Multimode Fiber

Multimode and single-mode optical fiber cables are two different cable types in optical networking. Using a larger core size, multimode fiber cable allows multiple light signals to be transmitted in a single fiber over short distances. Multimode fiber systems offer flexible, reliable and cost effective cabling solutions for local area networks (LANs), storage area networks (SANs), central offices and data centers. Unlike the complex classifications of single-mode fiber, multimode fiber is usually divided into four types of OM1, OM2, OM3, OM4. “OM” is abbreviated for optical multimode, and it is specified by the ISO/IEC 11801 international standard. Of course, these four types of multimode fiber have different specifications (as shown in the following table). The article will compare these four kinds of fibers from the side of core size, bandwidth, data rate, distance, color and optical source in details.

specifications-of-multimode-fiber

Core Size

Multimode fiber is provided with the core diameter from 50 µm to 100 µm. Apart from OM1 with a core size of 62.5 µm, other three types are all using the 50 µm. The thick core size makes them able to carry different light waves along numerous paths without modal dispersion limitation. Nevertheless, in the long cable distance, multiple paths of light can cause signal distortion at the receiving end, resulting in an unclear and incomplete data transmission. And this is why all the types of multimode fiber can only be used for short distance.

Bandwidth

Bandwidth is the bit-rate of available or consumed information capacity expressed typically in metric multiples of bits per second. The higher bandwidth is, the faster transmission speed can be. According to overfilled launch (OFL) and effective modal bandwidth (EMB) measurements, OM1 and OM2 can only support OFL, but OM3 and OM4 are able to support both measurements. At the wavelengths of 850/1300 nm under OFL, the respective bandwidth of OM1, OM2, OM3, OM4 is 200/500 MHz*km, 500/500 MHz*km, 1500/500 MHz*km and 3500/500 MHz*km. And at the wavelength of 850 nm under EMB, the bandwidth of OM3 is 2000 MHz*km and OM4 even reaches 4700 MHz*km.

Data Rate

Data rate is a technical term that describes how quickly information can be exchanged between electronic devices. With a higher data rate, the transmission can be more effective. OM1 and OM2 support the Ethernet standards from 100BASE to 10GBASE with a minimum data rate of 100 Mbps and a maximum data rate of 10 Gbps. Compare with OM1 and OM2, OM3 and OM4 are enhanced to support much higher data rates of 40 Gbps and 100Gbps in 40G and 100G Ethernet.

Distance

Multimode fiber is typically used for short distance transmission. But the maximum reaches are varied in different multimode fiber types. Also, on account of different data rates, the transmitting distances are different. However, the common feature is that OM1 always supports the shortest distance yet OM4 supports the longest. For instance, based on the same data rate of 10 Gbps, the maximum reach of OM1 is 33 m, OM2 is 82 m, OM3 is 300 m and OM4 is 550 m. Thus, if a medium-sized transmission is required, OM3 and OM4 are the best choices.

Color & Optical Source

The outer jacket can also be a method to distinguish OM1, OM2 from OM3, OM4. The common jacket color of OM1 and OM2 is orange, and OM3, OM4 are in aqua. In addition, OM1 and OM2 are using a light-emitting diodes (LEDs) optical source but OM3 and OM4 adopt the vertical-cavity surface-emitting laser (VCSELs) optical source.

color-and-optical-source-of-multimode-fiber

Application

OM1 and OM2 are widely employed for short-haul networks, local area networks (LANs) and private networks. OM3 is applied to a larger private networks. Different from the previous multimode types, OM4 is more advanced to be used for high-speed networks in data centers, financial centers and corporate campuses. The video below demonstrated the applications and differences between OM1, OM2, OM3, OM4 and OM5 multimode fibers.

Conclusion

It is very important to choose the right fiber type for your application. Future-proofing network design is crucial for network planning, but there is often a cost for that speed. With a higher performance, OM3 and OM4 are definitely more expensive than OM1 and OM2. So plan well and spend wisely.

Related Article: Applications of Tight-Buffered Distribution Cable
Multimode Fiber Types: OM1 vs OM2 vs OM3 vs OM4 vs OM5

Guide to Multimode Fiber Cabling in 40/100G Migration

Nowadays one and 10 Gbqs data rates are not adequate to meet the continued requirement for expansion and scalability in the data center, thus technology evolves and standards are completed to define higher data rates such as 40/100G Ethernet. In the meanwhile the cabling infrastructures installed today must provide scalability to accommodate the need for more bandwidth in support of future applications. OM3 and OM4 multimode cabling solutions have been proven to be a cost-effective solution for 40G data center. Today’s article will make you familiarize with this new Gigabit Ethernet and OM3/OM4 cabling to help you smoothly upgrade to 40G Ethernet.

Multimode Fibers in Data Center

Multimode fiber is more popular in data centers than singlemode fiber. Many people may know the reason—budget. Because the price of multimode fiber is typically much lower than singlemode fiber. Additionally, multimode fibers utilizes the low cost 850nm optical transceiver for both serial and parallel transmission. While singlemode fiber uses the expensive 1310nm and 1550nm transceiver and duplex fiber wavelength division multiplexing (WDM) serial transmission. Therefore, most data center designers would choose multimode fiber for 40/100G transmission.

OM3 and OM4 cable

There are four common types of multimode fibers available in the market—OM1, OM2, OM3 and OM4. Recently OM3 and OM4 cables are gradually taking place of OM1 and OM2 multimode cable. OM3 and OM4 are laser-optimized multimode fibers with 50/125 core, which are designed to accommodate faster networks such as 10, 40 and 100 Gbps. Compared with OM1 (62.5/125 core) and OM2 (50/125 core), OM3 and OM4 can support high data rate and longer distance. This is why OM3 and OM4 is more popular in data center.

The Ratification of IEEE 802.3ba

The Institute of Electrical and Electronics Engineers (IEEE) 802.3ba 40G/100G Ethernet standard was ratified in June 2010. According to this standard, it includes detailed guidance for 40/100G transmission with multimode and singlemode fibers. But the standard does not have guidance for Category-based unshielded twisted-pair or shielded twisted-pair copper cable.

OM3 and OM4 are the only multimode fibers included in 40/100G standard. Because multimode fiber uses parallel-optics transmission instead of serial transmission due to the 850-nm vertical-cavity surface-emitting laser (VCSEL) modulation limits at the time the guidance was developed. Compared to traditional serial transmission, parallel-optics transmission uses a parallel optical interface where data is simultaneously transmitted and received over multiple fibers. Table 2 shows the IEEE standards for 40 and 100 GbE.

IEEE standards for 40 and 100 GbE

The 40G and 100G Ethernet interfaces are 4x10G channels on four fibers per direction, and 10x10G channels on 10 fibers per direction, respectively. For 40GBASE-SR4 transceivers, it utilizes multimode fiber for a link length of 100m over OM3 and 150m over OM4. QSFP-40G-SR4 is Cisco 40GBASE-SR4 QSFP+ that can both operate over OM3 and OM4 cables to achieve 40G connectivity just as FTL410QE2C.

OM3 or OM4?

As noted before, OM3 and OM4 can meet the requirement for 40G migration cabling performance, that’s why they are being widely utilized in 40/100G migration. But OM3 and OM4, which is better for your infrastructure? There is no exact answer to this question as numerous factors can affect the choice. The working environment and the total costs are always the main factors to be considered when selecting OM3 or OM4 multimode cable.

OM3-and-OM4

OM3 is fully compatible with OM4. They use the same optical connector and termination of connector. The main difference between them is in the construction of fiber cable that makes OM4 cable has better attenuation and can operate higher bandwidth at a longer distance than OM3. On the other hand, the cost for OM4 fiber is higher than OM3. As 90 percent of all data centers have their runs under 100 meters, choosing OM3 comes down to a costing issue. However, in the long term, as the demand increases, the cost will come down. OM4 will become the most viable product in the near future.

Conclusion

No matter choosing OM3 or OM4 for your infrastructure, 40G migration is in the corner. OM3 and OM4 multimode cable featured by the high performance and low cost are the perfect solution for 40/100G migration. Fiberstore is committed to provide the best-service and high-quality products to customers. Our comprehensive range of products in OM3 and OM4 offer customers the ability to create the optimal network. For more information, you are welcome to contact us.

The Relationship between the Cut Off wavelength and Optical Fiber

What is cut off wavelength? When many people see the item they may ask such question. Well, cut off wavelength can be defined as the wavelength below a singlemode fiber wavelength and they usually acts as multimode fiber, meaning it will allow propagation of more than one mode at a time. In another word, cut off wavelength above singlemode operation but it is ensured in a singlemode fiber.

Fiber cut off wavelength depends on the method of fixing the fiber. We all know that fiber optic cable can be putted into loose tubes or tightly coated with elastomeric or PVC or Nylon, to make tight buffered fiber or the matrix to be fiber optic ribbon. Cut off wavelength reduces the numbers of bends in fiber, so the cut off wavelength plays an important role in singlemode fiber at the defining the wavelength region of singlemode fiber. It reminds me that I have met a product from Corning, it mainly told us the cut off wavelength is the quite important for the fiber in defining the region of singlemode operation and then Corning said, bends and stress makes the cut off wavelength to a lower value.

Cut-off wavelength is the wavelength above which an optical fiber will allow singlemode transmission. Cut off wavelength can also be defined as the wavelength below which multimode transmission starts. It just means that above a certain wavelength, multiple modes stopped and singlemode optical fiber (Related product: singlemode simplex fiber) is designed to a mode for transmission. Cut off wavelength is also a unique parameter of single mode fiber. There are two points we should know that normal cable and installation condition all reduce the cut off wavelength. The cable wavelength is more important than fiber cut off wavelength.

fiber mode

As for the multimode fiber, why we do not talk about it? Well, because the cut off wavelength is the wavelength below which multimode transmission. (Related product: multimode fiber patch cable). The fiber mode transmission acts as the figure. Thus, we also can see that cut off is also the feature of singlemode fiber, it is an unique characteristic for singlemode fiber. Thus it is clear that cut-off wavelength determines the fate of single mode transmission. ITU-T recommend that the cut off wavelength less than 1260nm or 1260nm for singlemode fibers. It means that the wavelength that below 1260nm is an acceptable single mode. We know that the 1310nm and 1550nm wavelength are used widely and with the introduction of DWDM and shifted fiber, 1260nm wavelength is not more acceptable than 1310nm. It means that singlemode fiber will allow a wavelength mode over 1261nm. Cut off wavelength is important for singlemode fiber, because it is the standards of condition and singlemode fiber to allow single mode transmission. Warm tips: Fiberstore is a famous fiber optic patch cords supplier. If you want to get related singlemode and multimode fiber cable, you can get them from here easily.