Tag Archives: fiber optic patch cord

Overview of 16 Gbps Fiber Channels

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Offering considerable improvements from previous FC speeds, 16 Gbps FC uses 64b/66b encoding, retimers in modules, and transmitter training. Doubling the throughput of 8 Gbps to 1,600 Mbps, it uses 64b/66b encoding to increase the efficiency of the link. 16 Gbps FC links also use retimers in the optical modules to improve link performance characteristics, and electronic dispersion compensation and transmitter training to improve backplane links. The combination of these technologies enables the 16 Gbps FC to provide some of the highest throughput density in the industry, making data transfers smoother, quicker, and cost-efficient.

Although 16 Gbps FC doubles the throughput of 8 Gbps FC to 1600MBps, the line rate of the signals only increases to 14.025 Gbps because of a more efficient encoding scheme. Like 10 Gbps FC and 10 Gigabit Ethernet (GbE), 16 Gbps FC uses 64b/66b encoding, that is 97% efficient, compared to 8b/10b encoding, that is only 80% efficient. If 8b/10b encoding was used for 16 Gbps FC, the line rate would have been 17 Gbps and the quality of links would be a significant challenge because of higher distortion and attenuation at higher speeds. By using 64b/66b encoding, 16 Gbps FC improves the performance of the link with minimal increase in cost.

To remain backward compatible with previous Fiber Channel speeds, the Fiber Channel application specific integrated circuit (ASIC) must support both 8b/10b encoders and 64b/66b encoders.

As seen in Figure 2-1, a Fiber Channel ASIC that is connected to an SFP+ module has a coupler that connects to each encoder. The speed-dependent switch directs the data stream toward the appropriate encoder depending on the selected speed. During speed negotiation, the two ends of the link determine the highest supported speed that both ports support.

The second technique that 16 Gbps FC uses to improve link performance is the use of retimers or Clock and Data Recovery (CDR) circuitry in the SFP+ modules. The most significant challenge of standardizing a high-speed serial link is developing a link budget that manages the jitter of a link. Jitter is the variation in the bit width of a signal due to various factors, and retimers elliminate most of the jitter in a link. By placing a retimer in the optical modules, link characteristics are improved so that the links can be extended for optical fiber distances of 100 meters on OM3 fiber. The cost and size of retimers has decreased significantly so that they can now be intergrated into the modules for minimal cost.

The 16 Gbps FC multimode links were designed to meet the distance requirements of the majority of data centers. Table 2-2 shows the supported link distances over multimode and single-mode fiber 16 Gbps FC was optimized for OM3 fiber and supports 100 meters. With the standardization of OM4 fiber, Fiber Channel has standardized the supported link distances over OM4 fiber, and 16 Gbps FC can support 125 meters. If a 16 Gbps FC link needs to go farther than these distances, a single-mode link can be used that supports distances up to 10 kilometers. This wide range of supported link distances enables 16 Gbps FC to work in a wide range of environments.

Another important feature of 16 Gbps FC is that it uses transmitter training for backplane links. Transmitter training is an interactive process between the electrical transmitter and receiver that tunes lanes for optimal performance. The 16 Gbps FC references the IEEE standards for 10GBASE-KR, which is known as Backplane Ethernet, for the fundamental technology to increase lane performance. The main difference between the two standards is that 16 Gbps FC backplanes run 40% faster than 10GBASE-KR backplanes for increased performance.

Fiberstore introduces it’s new OM4 Laser-Optimized Multimode Fiber (LOMMF) “Aqua” cables, for use with 40/100Gb Ethernet applications. These new technology, 50/125um, LC/LC Fiber Optic cables, provide nearly three times the bandwidth over conventional 62.5um multimode fiber, with performance rivaling that of Singlemode cable, at a much reduced cost. LOMMF cable allows 40/100Gb serial transmission over extended distances in the 850nm wavelength window, where low-cost Vertical Cavity Surface Emitting Lasers (VCSELs) enable a cost-effective, high-bandwidth solution. OM4 fiber optic patch cord is ideally suited for LAN’s, SAN’s, and high-speed parallel interconnects for head-ends, central offices, and data centers. Tripp Lite warrants this product to be free from defects in material and workmanship for Life. Now the following is the OM4 fiber from Fiberstore.

OM4 SC to SC fiber patch cord feature an extremely high bandwidth–4700MHz*km, more than any other mode. They support 10GB to 550 meters and 100GB to 125 meters. These cables are suitable for high-throughput applications, such as data storage. These cables are fully (backwards) compatible with 50/125 equipment as well as with 10 gigabit Ethernet applications. These connectors utilize a UPC (Ultra Physical Contact) polish which provides a better surface finish with less back reflection. With the OM4 cables, you can use longer lengths than OM3 cables while still having an excellent connection.

We offer a huge selection of single and multimode patch cords for multiple applications: mechanical use, short in-office runs, or longer runs between and within buildings, or even underground. Gel-free options are available for less mess, and Bend Insensitive cables for minimizing bend loss, which can be difficult to locate and resolve.

Related Article:  Which Patch Cable Should I Choose for My Optical Transceiver?

The Fiber Optic Patch Cord Reliability

Fiber optic patch cords are one of the simplest elements in any optical network, consisting of a piece of fiber optic cable with a connector on each end. Despite its simplicity, the Fiber Optic Patch Cord can have a strong effect on the overall performance of the network. The majority of problems in any network occur at the physical layer and many are related to the patch cord quality, reliability, and performance. Therefore, using patch cords that are more reliable helps reduce the chance of costly network downtime. This article mainy the patch cord reliability.

Network designers would prefer components with a history of proven long-term performance. However, since optical networking is a relatively new technology, there is no significant long-term data for many components. Therefore, designers must rely upon testing from the component manufacturer or supplier that can simulate this history and assure the quality and reliability over the life of the network. This paper discusses the importance of quality, reliability, and performance as they relate to industry standards and manufacturing practices. The performance of the patch cord is also studied using a “perfect patch cord” and polishing observations as tools to understand patch cord principles.

Patch cord reliability is guaranteed not only by using quality components and manufacturing processes and equipment, but also by adherence to a successful Quality Assurance program. While patch cords themselves are typically tested 100% for insertion loss and return loss, if applicable, there are many other factors that need to be monitored to insure the quality of the patch cord.

One of the most important factors is the epoxy. Epoxies typically have a limited shelf life and working life, or “pot life.” This information is readily available from the manufacturer. It is absolutely necessary that both of these criteria be verified and maintained during manufacture. Epoxy beyond its expiration date needs to be discarded. Chemical changes affecting the cured properties of the epoxy can occur after this date. This date can also be dependent on storage conditions, which need to be observed.

Most epoxies used in fiber optic terminations are two-part epoxies and, while they cure at elevated temperatures, preliminary cross-linking will begin upon mixing. Once this has started, the viscosity of the epoxy can begin to change, making application more difficult over time. The epoxy can become too thick to fill the ferrule properly and too viscous to enable a fiber to penetrate, causing fiber breakage.

Many of the tooling used in patch cord assembly also has periodic maintenance and a limited tool life. This includes all stripping, cleaving and crimping tools. Most stripping tools, whether they are hand tools or automated machines, can be damaged by the components of the cable, most notably the aramid yarn strength members. Buffer strippers will dull with prolonged usage, increasing the likelihood that they will not cleanly cut the buffer. This can lead to overstressing the fiber when the buffer is pulled off. When a cleaving tool wears out and a clean score is not made, it is almost impossible to detect during manufacturing. However, the result could be non-uniform fiber breakage during the cleave, which can result in either breaking or cracking the fiber below the ferrule endface. In this instance, the connector will have to be scrapped. Even crimp tools require periodic maintenance to insure the proper forces and dimensions are consistent. Crimp dies also have a tendency to accrue epoxy build-up, which can affect the crimping dimensions and potentially damage the connector.

The integrity of the incoming materials and manufacturing processes, once specified, needs to be adhered to all the appropriate guidelines and procedures. The importance of these materials not only has a strong influence on product reliability, but also on product performance.

Fiber optic patch cords are fiber optic cables used to attach one device to another for signal routing. It compresses in the entire electric network plank and room that wall plank and the flexibility cabinet needs, causes such the person who passes room merely considerably traditional FC,LC,ST and SC’s connection box in parts.Intelligently the bright and beautiful corporation adopts well-developed technique and installation, and carrying on scale manufacture, the produce performance is good, and the quality is steady dependable. Fiberstore manufactures fiber optic patch cables, fiber optic patch cords, and pigtails. There are LC, SC, ST, FC, E2000, SC/APC, E2000/APC, MU, VF45, MT-RJ, MPO/MTP, FC/APC, ST/APC, LC/APC, E2000, DIN, D4, SMA, Escon, FDDI, RoHS compliant, LSZH, Riser,Plenum, OFNR, OFNP, simplex, duplex, single mode, 9/125, SM, multimode, MM, 50/125, 62.5/125; armored fiber optic patch cords, OM4 patch cord, waterproof fiber optic patch cords, ribbon fiber optic cables and bunched fiber optic cables.

Related Article:  Which Patch Cable Should I Choose for My Optical Transceiver?

Video Patch Panel With Patch Cable

The jacks commonly used in patch panels in the U.S. conform to Western Electric standard dimensions. The number of insertion cycles a jack can endure should be rated in the tens of thousands. The factors affecting the life and reliablility of a jack include contact wear and failure of the termination switch. Descirable features include the following:

● Contacts fully isolated from the panel.
● Sealed metal housing to keep out contaminants and provide EMI protection.
● Easy replacement from the front of the panel.
● Low VSWR (below 600 MHz)
● High signal isolation (40 dB)
● 75 Ω characteristic impedance.
● Wide designation strips, making it easier to label the field and to allow more flexibility in selecting names that will fit on the lables.

If a patch cable is inserted in the signal path of a timed video system, it will delay the signal by an amount determined by its length and physical properties. The patch thereby alters the timing of the signal path. This can be avoided by using phase-matched normal-through fiber patch panels. The design of these patch panels anticipates the delay caused by a fixed length of patch cable by including that length in the loop-through circuit.

With phase-matched panels, the normaling connection in each connector module includes a length of cable that provides a fixed delay through the panel, usually 3 ft (0.914m). If a patch cord of the same length as the internal cable is used to make connections between patch points, the delay will be the same as that of the normal-through panel. When a fiber optic patch cord is plugged in, it is substituted for the loop cable through the swiching mechanism normally used in normalled patch conncetors. Thus, critical timing relationships can be maintained. Figure 6.21 shows a phase-matched patch panel.

In a normal uncompensated patch panel, when a cable is used to patch between two points on the panel, the length of the patch cord is added to that of the cables connected to the patch. The additional cable length delays the signal by approximately 1.52 ns/ft (5 ns/m). To avoid the delay probles associated with conventional patch panels, phase-matched normal-through video patch panels should be used.

If phase-matched patch panels are used, all of the patch cord must be the same length as the delay built into the patch panel. Obviously, if all of the patch cords must be the same short length for the phase-matched panel, it would not be possible to patch between panels that are separated by a longer distance than the cord can reach. This limitation should be considered when laying out patch panels in a rack.

Color-coded cables can be specified. When different-length patch cords are specified, different colors can be used to distinguish one length from another.

Fiberstore specializes in fiber optic patch cable assemblies and fiber optic network devices manufacturing since 1995, we are known as the fiber optic cable manufacturer for the excellent products quality, competitive prices, fast delivery and good service.  Our fiber optic cables are available with combinations of LC, SC, ST, FC, and MTRJ connectors and come in 1, 2, 3, 5, and 10 meter lengths (and OM3 cables up to 30 meters).  We offer LC fiber optic cable, SC fiber optic patch cables, SC LC fiber patch cable ect. We not only offer OEM fiber optic patch cord assemblies to some world leading companies in this industry, but we also cooperate with many other companies from all over the world and support these partners to win in the market.

10BASE-T Collision Domain Cabling Topology

The overall topology of a 10BASE-T LAN is a tree of stars, as illustrated in Figure 1. The LAN in Figure 2 is constructed around four hubs and is a single collision domain. Each segment is at most 100 meters in length. The longest path throught the network passes through four hubs and crosses five sements.

An unbroken 100-meter run often is used to connect two hubs or to join a hub to a bridge. However, a horizontal cable run between a workstation and a hub normally is broken up into pieces, as Figure 3 shows. At the station end, a NIC is connected to a telecommunications outlet by a short cable called a patch cord. With the wiring closet at the other end, patch cords are used to complete the connection to a specific hub or switch.

A patch cord also is called a patch cable or a jumper cord. A patch cord that connects a user’s computer to an outlet often is called a work area cable. A Fiber Optic Patch Cord that connects a device to a hub or switch in a wiring closet often is called an equipment cable.

A typical breakdown is 90 meters for the long run between the telecommunications outlet and patch panels in the wiring closet and up to 10 meters for the patch cords used at each end. The patch cord connection between the station and the telecommunications outlet normally is limited to a length of 3 meters, at most.

Patch panels in a wiring closet enable the connections between end-user stations and hubs or switches to be rearranged by unplugging and replugging patch cables.

The patches shown at the top of Figure 3 are called interconnects. A station is attached to a new hub by unplugging the patch cable from the old hub and plugging it into the new hub. The patches shown in the lower part of Figure 4 are called cross-connects. Cables connected to the hubs do not need to be touched. An attachment is changed by plugging one end of a patch cord into a different socket. Cross-coonects are very convenient. However, they can degrade signals since they introduce more connector hardware into the cable patch.

Fiberstore Inc is one of the renowned manufacturers, suppliers and exporters of fiber optic patch cable, such  as LC fiber optic cable, multimode fiber patch cable, single mode fiber SC to LC, custom fiber patch cables, MTP/MPO fiber patch cable, Fiber optic pigtails, and much more.  with a factory in China. With years of experience in the line of making , we are known for our outstanding performance in the industry. We have helped ourselves as one of the leading brand in China. We constantly upgrade our products to meet the international standards. We hold a team of professionals, which provides on time deliveries with high quality. Our sincerity and hard work has helped us match our quality with international standards.

Patch Cord Optical Power Loss Measurement

Measurement of fiber optic cable loss is an established practice that has been performed for many years. However over time, the performance of fiber optic equipment has improved, so occasionally it is useful to perform a practical re-assessment of the accuracy of these measurements.

Multimode patch cord optical loss power measurement is performed using the stpes described in ANSI/TIA-526-14, method A. The fiber optic patch cord is substituted for the cable plant. Because patch cords are typically no longer than 5m, the loss for the optical fiber is negligible and testing can be performed at 850nm or 1300nm. The loss meausured in this test is the loss for the patch cords connector pair. ANSI/TIA-568-C.3 states that the maximum loss for a connector pair is 0.75dB.

After setting up the test equipment as described in ANSI/TIA-526-14, method A, clean and inspect the connectors at the ends of the patch cords to be tested. Verity that your test jumpers have the same optical fiber type and connectors as the patch cords you are going to test. The transmit jumper should have a mandrel wrap or modal conditioner depending on the revision ANSI/TIA-526-14 being used for testing. Ensure that there are no sharp bends in the test jumpers or patch cord during testing.

Because both patch cord connectors are easily accessible, optical power loss should be measured in both directions. The loss for the patch cord is the average of the two measurements. If the loww for the patch cord exceeds 0.75dB in either direction, the patch cord needs to be repaired or replaced.

For testing the loss of a patchcord, you only need an 850 nm LED light source for multimode cable or 1310 laser for singlemode, a fiber optic power meter and some reference patchcords. Just remember that the patchcords used for references in testing must be good for tests to be valid, so you test them as you would other patchcords, just more often.

Testing patchcords is similar to testing any fiber optic cable. Use one reference patchcord to set a 0 dB reference. Connect a patchcord to test to the reference patchcord with a mating adapter. Connect the power meter to the other end of the patchcord and measure the loss. Since the length of the fiber is short, the loss contribution of the fiber is ignorable. And since one end of the cable is attached to the power meter, not another cable, you only measure the loss of the one connection between the reference cable and the cable under test, so you can test each connector individually.

To complete the testing of the patchcord, reverse the cable you are testing to check the connector on the other end. Sometimes you will find one bad connector and can replace it to make the patchcord useful again. But often the cost of replacing the connector may be higher than replacing the patchcord itself.

If your test equipment has different connectors than the patchcords you are testing, you will need hybrid reference cables with connectors compatible with the equipment on one end and the patchcord connectors on the other end. You will also need the correct connector adapters for your power meter.

Obviously, all reference cables used for testing must have high quality connectors to get reliable test results. Use this same method to test your reference cables against each other and discard any with high losses, usually those with losses over 0.5 dB.