A Brief Overview of 100G Transceivers and Cabling Solutions

Although 10G/40G has become the mainstream on telecommunication network market nowadays, service providers and enterprise data centers are still demanding higher data transmission speed to achieve higher level of performance and scalability, which explains why 100G Ethernet appeared on the scene. According to the statistics from market research company like IHS, 100G becomes a hit in the year of 2016. This post tends to give a brief overview of optical transceivers and cabling solutions for 100G Ethernet.

100G Ethernet Introduction

100 Gigabit Ethernet (100GbE) is the computer networking technology which was first defined by IEEE 802.3ba-2010 standard for transmitting Ethernet frames at rates of 100 gigabits per second. The 100G standards define numerous port types with different optical and electrical interfaces and different numbers of optical fiber strands per port. The mainly used 100G standards are showed in the following table.

100G Transceivers

Optical transceiver is considered to be a key component to ensure the flexibility and reliability of the whole system. The most commonly used 100G transceivers on the market are CFP, CFP2, CFP4 and QSFP28. The following part will introduce them in details.

CFP/CFP2/CFP4: The CFP (c form-factor pluggable) is a multi-source agreement (MSA) to produce a common form-factor for the transmission of high-speed digital signals. The “c” stands for the Latin letter C used to express the number 100 (centum), since the standard was primarily developed for 100 Gigabit Ethernet. The CFP transceiver can be used to support both single-mode fiber, multimode fiber and a variety of data rates, protocols, and link lengths. While the electrical connection of a CFP uses 10×10 Gbit/s lanes in each direction (RX, TX), the optical connection can support both 10×10 Gbit/s and 4×25 Gbit/s variants of 100Gbit/s interconnects. With the improvement in technology, higher-density and higher-performance CFP2 and CFP4 transceivers are needed. CFP2 and CFP4 has the similar electrical connection with the CFP, but they specify a form-factor of 1/2 and 1/4 respectively in size of the original specification. When you use these transceiver modules, you should note that they are not interchangeable, but they can be inter-operable at the optical interface with appropriate connectors. The image below shows CFP, CFP2 and CFP4 transceivers.

QSFP28: QSFP28 is a hot-pluggable, high-density transceiver available in single-mode and multimode versions to support data center, cloud networks, and high-performance computing networks applications. Just as the 40G QSFP+ is implemented with four 10Gbs lanes, the QSFP28 uses four 25 Gbs lanes for an aggregate data rate of 100Gbs. Typically, there are two versions of QSFP28 transceivers, 100GBase-SR4 QSFP28 for short distance data transmission and 100GBase-LR4 QSFP28 for long distance data transmission. The following picture shows these two types.

100G Cabling Solutions

100G Direct Cabling Solutions: There are various 100G direct cabling solutions available on the market. You can choose the appropriate one according to the data transmission distance that you require. For 100G short direct cabling, we can use 100GBase-SR4 QSFP28 and 100G QSFP28 to QSFP28 cables. As we all know, 100GBase-SR4 QSFP28 can support the length of up to 70 m and 100 m over OM3 and OM4 12 fiber multimode MTP cable respectively, and 100G QSFP28 to QSFP28 passive direct attach cable can support up to 5 m, while the 100G QSFP28 to QSFP28 active direct attach cable can support up to 10 m. For 100G long direct cabling, 100GBase-LR4 transceivers (including 100GBase-LR4 QSFP28, CFP, CFP2 and CFP4) are good choices. All of them can achieve the link length of up to 10 km on single-mode LC patch cables. Here shows a Cisco QSFP-100G-CU3M passive direct attach copper cable.

100G Breakout Cabling Solution: 100G QSFP28 to 4SFP28 direct attach copper cable (shown in the following picture) is the commonly used cable type for 100G breakout cabling applications. This cable provides connectivity between system units with SFP28 port on one side and four different SFP28 ports on the other side, which enables higher port bandwidth, density and configurability at a low cost and reduces power requirement in data centers.

Conclusion

People never stop chasing higher speed in every aspect of our daily life, so does in telecommunication networks. After the prevalence of 10G/40G, are you ready for 100G? Through the information that we have mentioned, hope you can get some basic knowledge to make good preparation for the coming of 100G.

What Makes Direct Attach Cable Preferable for 40/100G Migration?

As new applications, devices and architectures continue to demand ever higher speed networks, 40G and 100G Ethernet links are rapidly coming on line. Many vendors have put forward various solutions for 40/100G migration, including optical transceivers (like QSFP+ or QSFP+ 28), fiber cabling (like MPO/MTP breakout cable or MPO/MTP harness cable), and copper cables (like direct attach cable). Among these solutions, direct attach cable with unique advantages is more preferable for 40/100G migration. But why? The following part will explain the reasons in details.

What Is Direct Attach Cable?

Direct attach cable (DAC), also known as twinax cable, is a fixed assembly supporting high data speed that uses a small form-factor connector module as an optical transceiver at the either end of a length of cable. Generally, direct attach cable can be active and passive. The former one has active electronic components in the optical modules to improve the signal quality, while the latter one is mainly just a straight “wire” and contains a few components. With low cost, low power consumption and low latency, DAC has become popular in network industry and widely applied in storage area network, data center and higher performance computing connectivity to achieve the migration to 40/100G. The image below shows Cisco QSFP-H40G-CU1M compatible 40G QSFP+ Passive Direct Attach Copper Cable.

Unique Features of Direct Attach Cable

With many unique features, direct attach cable can satisfy the increasing demand for high speed data transmission. The main features of DAC are described in the following text.

• Low Price—DACs are much cheaper than the regular optics. Because the “transceiver” on both ends of DACs are not real optics. Compared with regular optical transceivers, the small form-factor connector modules are without expensive optical lasers and electronic components, and they’re just used to transmit the optical signals. Accordingly, the cost of DACs will be much lower. Besides, DACs in some case can be an alternative to optical transceivers as it eliminates the separable interface between transceiver modules and optical cable. Thus, direct attach cable is a more cost effective solution for 40/100G applications.
• Power Saving—A small electrical component is used in both active direct attach cable and passive direct attach cable to identify the modules on the end and cable type to the Ethernet interface. Compared to optical transceivers, DACs with this component consumes very litter power.
• Enough Data Rate for Various Applications—With the appearance of optical fibers which can support high data speed and achieve good performance in networks, many people may think that copper has been out of sight. Actually, DAC can also provide high speed input and output data. Currently, DACs are most commonly used for 10G and 40G applications. And with the development of technology, some direct attach cable can be used to achieve data transmission of 100G, or even 120G.
• Interchangeability—With the advancement of copper cable technology, copper DACs are interchangeable and hot swappable with fiber optic modules.

Summary

With a wide range of 40/100G solutions available on the market, direct attach cable becomes the preferable one for 40G/100G applications, since it takes the advantages of cost and power saving, enough data rate for various applications and excellent interchangeability. With the increasing demand for higher bandwidth, direct attach cables are continuing evolving. Fiberstore, as a professional manufacturer and supplier of optical equipment, has various direct attach cables in stock, such as 10G SFP+ DACs, 40G QSFP+ DACs, and 100G QSFP28 DACs. If you want to upgrade your network to 40/100G with direct attach cables, please visit FS.COM.

The Colorful World of LC Connector

Until few years ago, SC connector was the dominant interface available for fiber optic connections in LANs (local area networks) and data centers. However, the ever-increasing density in network deployment is requiring smaller connection interfaces. As the representative of small form factor (SFF) connectors, LC connector is the most widely used one for high-density connections. When we talking about LC connectors, many of us may think it is just a simple tool to achieve fast and easy field termination for fiber optic connectivity. Actually, the world of LC connector is far more colorful than you think. Besides traditional LC connector, there are various other types of LC connectors which are currently used in different applications. In this post, I’m going to introduce several widely known ones to take you into the colorful world of LC connector.

Features of LC Connector

Actually, connector can be both simplex and duplex. Simplex connector means only one fiber is terminated in the connector, while duplex connector means two fibers are terminated in the connector. The LC has some unique features to make it a preferable connector for high-performance networks.

The ferrule size of LC connector is 1.25 mm which is the half size of SC connector ferrule which is 2.5 mm. This change in size decreases the room by roughly 50% all over the network. LC makes things easier for movement, additions and modifications, thus preventing additional expenses. Besides, the LC connector uses an enhanced edition of the well-known, user friendly RJ-style telephone connector that offers a reassuring and clear click when connected.

Mini LC Connector

The mini LC uses current industry-standard LC connector, but it reduces the center spacing when the duplex clip is added. It is designed with a narrow ferrule pitch to work with the mini SFP (mSFP) transceiver. This accommodates the need for higher port density provided by the transceivers without compromising performance. The mini LC duplex connector looks virtually identical to a standard LC duplex, but is distinguishable with its black duplex clip and its 5.25 mm pitch versus the 6.25 mm used by standard LC duplex connector. The use of mini LC connector with mini SFP transceiver significantly reduces space in data centers. The following picture shows the differences of mini LC and standard LC.

Uniboot LC connector

With two LC connectors encased in a common housing with one boot, uniboot LC connector (shown in the picture below) features a changeable polarity option and reduction in size compared to standard LC connector. It allows the fiber polarity to be reversed at the time of cable assembly installation without exposing the fibers or needing any tools. This not only provides consistent quality and convenience, but also ensures system performance and reduces installation time. Besides, fiber patch cables terminated with uniboot LC connectors, are more preferable in data center applications, since they can offer high efficiency and easier cable management.

Secure Keyed LC Connector

Secure keyed LC connector offers a mechanical network security for organizations wanting to segregate networks due to privacy or security concerns. It is available in 12 colors, and each color represents a unique keying pattern which only allows connection when the color matches. Secure keyed LC connector can not only reduce risks and increase the security of network from incorrect patching of circuit, but also has low insertion loss and excellent durability. The image below shows secure keyed LC connector in different colors.

Push-Pull LC Connector

Before the invention of push-pull LC connector, the LC adapter spacing was limited by the room required to reach the standard LC connector with special tools. And the overall height of standard LC connectors also required a small vertical space above & below the LC adapters. Thanks to the push-pull LC connector or LC-HD connector, these issues can be perfectly solved. LC-HD connector is terminated with a tab which makes it easier to push or pull connector into/out the densely loaded panels without the need for special tools. Besides, the low profile LC-HD connector, together with its push-pull tab allows LC adapters to be stacked with absolutely no vertical space, which increases panel density to its highest possible.

Summary

The world of LC connector is colorful, and when choosing LC connectors, the standard LC is not the only option. There are a range of LC connectors applied in different circumstances can be selected from, such as uniboot LC for easier cable management, LC-HD for space saving and secure keyed LC for safe network transmission. And the evolution of LC connector never stops. With the increasing of various application requirements and the development of technology, there will be more and more new LC connectors to join in. If you need to purchase these LC connectors or LC fiber cables, please visit FS.COM.

How Many Media Options Do We Have for 10 Gigabit Ethernet?

As the added complexity, power needs and cost of additional GbE adapters will not allow customers to scale to meet current and future I/O demands, it is necessary to migrate to 10GbE. Moving to 10GbE addresses the increased bandwidth needs while greatly simplifying the network and lowering power consumption by replacing multiple GbE connections with a single or dual-port 10GbE connection. Generally, there are three main media options for 10 Gigabit Ethernet: 10GBase-CX4, 10G SFP+, and 10GBase-T. The following text will briefly introduce these three options, including their advantages, disadvantages and applications, to help you better understand them.

10 Gigabit Ethernet Overview

10 Gigabit Ethernet, defined by IEEE 802.3ae-2002 standard, is a group of computer networking technologies for transmitting Ethernet frames at a rate of 10 gigabit per second. Unlike previous Ethernet standards, 10G Ethernet defines only full duplex point-to-point links which are generally connected by network switches. Like previous Ethernet standards, 10G Ethernet can use either fiber or copper cabling, but higher-grade copper cables are required, such as cat6a or cat7 cables for links up to 100 m. Since it can support higher bandwidth and provide better performance than previous Ethernet networks, 10G Ethernet has been ubiquitous in most data centers.

Three Media Options for 10G Ethernet

10GBase-CX4

10GBase-CX4 is the first 10G copper standard published by 802.3 (as 802.3ak-2004). Using Infiniband 4×cabling with each lane carrying 3.125 GBd of signaling bandwidth, CX4 can have a maximum distance of 15 meters. 10GBase-CX4 offers the advantages of low power, low cost and low latency, but it has a bigger form factor and more bulky cables than the newer single lane SFP+ standard and a much shorter reach than fiber or 10GBase-T. The applications of 10GBase-CX4 today are very rare, although some network vendors offer CX-4 interfaces which can be used for either 10GBase or for stacking of switches at slightly lower latency.

10G SFP+

SFP+’s support for both fiber optic cables and DAC makes it a more flexible solution than CX4. Here will introduce SFP+ fiber optic cable and SFP+ DAC cable respectively.

1. SFP+ Fiber Optic Cable

There are various of SFP+ modules available on the market which can be cabled with fiber, providing low latency and long transmission distance, such as 10GBase-SR, 10GBase-LR and 10GBase-ER. Take Finisar FTLX8571D3BCL as an example, it can work through a multimode optical cable to support the link length of up to 300 m, achieving the maximum data rate of 10.51875Gbps. Generally, fiber cabling coupled with SFP+ transceivers offers the best power consumption footprint, however it is more expensive than other 10G media types.

2. 10GBase SFP+ DAC

10G SFP+ DAC (shown in the following picture) is a lower cost alternative to fiber, but its reach for passive cables is limited to 7 meters, and it is not backward-compatible with existing GbE switches. Since DAC requires the purchase of an add-in adapter and uses a new top-of-rack (ToR) switch topology, it is much more expensive than structured copper channels and cannot be field-terminated. Besides, with the deployment of ToR, it is very difficult to use all the switch ports purchased due to the generally lower number of server adapter ports and the limited reach of the cables. The unused ports carry an initial cost outlay and require maintenance costs, making them expensive on an ongoing basis.

10GBase-T

10GBase-T, or IEEE 802.3an-2006, is a standard released in 2006 to provide 10G connections over unshielded or shielded twisted pair cable, which can support the distances up to 100 meters. With backward-compatibility, 10GBase-T, cabled with cat6a or great cabling, can be used in existing 1GbE switch infrastructures, which helps IT managers to keep costs down while offering an easy migration path to 10GbE. The main drawback to 10GBase-T is the very high power consumption per port, around 6 w per port for current devices. However, since it retains the incredibly simple cabling of other -T standards, 10GBase-T has gained increasing popularity in recent years.

Conclusion

10G Ethernet has become a common choice for enterprise, metropolitan and wide area networks. Three 10G media options have been introduced above—10GBase-CX4, 10G SFP+ and 10GBase-T. If you want to choose the right one for your 10G infrastructure, you should take many factors into consideration, like power consumption, cost, transmission distance, etc.

Which Cable Jacket Is Best for Your Application?

When buying bulk cables or cable assemblies, you’re probably concerned about things like conductor AWG size, shielding for EMI/RFI, connector molding construction, etc. Why would you spare a thought to the jacket that just goes around the conductors? Actually, cable jacket is much more important than you may think. Choosing the wrong cable jacket can have implications in a range of things, from extending the life of your cable, to using the cable in the field. The following part will briefly introduce several commonly used cable jackets for your references.

The Importance of Cable Jacket

The cable jacket is the first line of mechanical, moisture, flame and chemical defense for a cable. More specifically, the jacket provides protection for the shielding and conductors. It protects the cable from mechanical damage during and after installation. Jackets are not intended to replace cable armors, but they can provide a fairly high level of moisture and chemical protection along with UV and ozone protection. The following image shows the structure of optical cable.

Commonly Used Cable Jackets

PVC

PVC (polyvinyl chloride) is the most widely used nonmetallic jacketing material in the wire and cable industry. Starting in 1935, when it first became available, the use of PVC grew rapidly because of its low cost, easy processing and excellent combination of overall properties including fire and chemical resistance. Nevertheless this kind of jacket also has shortcomings. For example, PVC is a thermoplastic material, so it cannot take high temperature. In industries that handle large amounts of heated material, or where there are the possibilities of excessive heat, the use of PVC should be avoided, because of its tendency to melt or deform when heated to a high temperature.

LSZH

Increasing concern for worker safety and electronic circuit life circle is driving demand for low-smoke,zero-halogen (LSZH) material. LSZH is composed of thermoplastic or thermoset compounds which will emit limited smoke and no halogen when wires or patch cables are damaged by fire or a short circuit fault. This type of jacket is typically used in poorly ventilated areas such as aircraft, rail cars, or ships. It is becoming very popular and, in some cases, a requirement where there is a need for the protection of people and equipment from toxic and corrosive gas.

PUR

Polyurethane, also referred to as PUR, is a thermoplastic material, commonly used in harsh environment. PUR is resistant to swelling and degradation when exposed to water for a long period of time, making it suitable for undersea equipment, like submarine cables. Besides, its flexibility and hardness allow it become a useful compound for isolating electronic components from vibration and shock. However, the only demerit of PUR jacket is that it is more expensive than other types of common jackets.

EPR

EPR (ethylene propylene rubber) is a chemically cross-linked, thermosetting high-temperature rubber insulation. It has excellent electrical properties combined with outstanding thermal stability and flexibility. It can also withstand the cold temperature down to -60 Celsius degree. With fairly good high-temperature characteristics overall, when formulated correctly, EPR can be rather flame retardant as well.

Silicon

As a form of synthetic rubber, silicon has excellent electrical properties plus ozone resistance, low moisture, weather and radiation resistance. While silicon rubber burns slowly, it forms a non-conductive ash which, in some cases, can maintain the integrity of the electrical circuit. Silicon jacket is typically used for applications where lots of wire bending are required.

Conclusion

Cable jacket is not as simple as you think. When you choose patch cables or coppers, you should also take jacket factor into consideration. There are various types of cable jackets available on the market and each of them can be used in different circumstances. After reading this passage, hope you can choose the best one for your applications.

Comparison Between FBT Splitter and PLC Splitter

To cope up with modern day fiber optic network’s needs and stringent requirements on performance, security, safety and modularity, many new technologies and high-performance equipment are needed. Fiber optic splitter, which can distribute and combine energy with low cost and high reliability, is one of them. Generally, based on different working principles, optical splitter can be divided into two types—FBT splitter and PLC splitter. Many people may wonder what differences between them and which one we should choose for our project. To better understand these two splitters, the following part will make a comparison between them.

Basic Concept of FBT Splitter and PLC Splitter

FBT Splitter

Based on traditional technology, FBT (fused biconical taper) splitter contains two fibers which are placed closely together, typically twisted around each other and fused together by applying heat while the assembly is being elongated and tapered. It is made out of materials that are easily available, such as steel, fiber, hot dorm. All of these materials are low-price, making the device itself inexpensive. With its low cost and easy installation, FBT splitters are widely adopted in passive networks, especially for instances where the split configuration is smaller (like 1×2, 1×4, 2×2, etc.). The following image shows a 1×2 FBT splitter.

PLC Splitter

PLC (planar lightwave circuit) splitter is the recent addition in fiber optic technology to exhibit uniform signal splitting among the most advanced optical networks. PLC splitter is a fully passive optical branching device that is based on planar light wave circuit technology and precision aligning process, which can evenly split or distribute a single optical signal/input into many outputs with high accuracy and minimal loss in an efficient manner. PLC splitter is a high-quality device, especially for passive internet (EPON, GPON, BPON). Here is a picture of 1×16 PLC splitter.

Differences Between FBT and PLC Splitter

There are many differences between FBT and PLC splitter, and the following part will put more emphasis on the aspects of fabrication method, operating wavelength, splitter ratio, size of splitter and cost.

• Fabrication Method: For FBT splitter, there are two or more pieces of optical fibers bound together inside the fused-taper fiber device. The fibers are then drawn out according to the output branch and ratio with one fiber being singled out as the input. PLC splitter consists of one optical chip and several optical arrays depending on the output ratio. And the optical arrays are coupled on both ends of the chip.
• Operating Wavelength: FBT splitter only supports three wavelengths (850 nm/1310 nm/1550 nm) which makes this device less customizable for different purposes, but PLC splitter can operate over wavelengths from 1260 nm to 1650 nm, covering various PON standards, so it can be applied for a variety of applications.
• Split Ratio: A split ratio is the amount of light that is re-directed from the network to the monitor ports. The higher the split ratio, the better the performance. The split ratio of FBT splitter is up to 1:32, while the ratio of PLC splitter goes up to 64, which can provide a higher reliability.
• Size: FBT splitter, which utilizes traditional technology, is much bigger in size and cannot easily fit in all cabinet. Compared to FBT splitter, PLC splitter is much more compact and can save more space. Hence, it is more suitable for density applications.
• Cost: As we have mentioned above, FBT splitter is normally made by low-price materials, like steel or fiber, thus it has low cost than PLC splitter. Besides, the technology of the device manufacturing is relatively simple, which has the impact on its price as well. But for PLC splitter, it uses more complex semiconductor technology (lithography, etching, developer technology) production, making the price of this device higher.

Summary

Besides the differences that we have discussed above, there also exists many other differences between this two types of optical splitter, such as the spectral uniformity, temperature dependent loss,and the input/output fibers, etc. Both of these splitters have their own advantages upon different aspects. From this post, hope you can get a basic understanding of FBT and PLC splitter and next time when you choose optical splitter, you won’t feel confused.

10GBase-T – Ushering in the Era of Affordable 10Gb Ethernet

A variety of technological advancements and trends are driving the increasing need for 10GbE in the data center. There are many media options for 10G Ethernet on the market, such as 10GBase-CX4, SFP+ fiber and SFP+ direct attach cable (DAC), etc. However, those options have more or less limitations that will delay the adoption of 10GbE in many data centers. For example, the deployment of 10GbE—using SFP+ connections to accommodate either fiber optics or DAC connectivity—improved the I/O capability for virtualized servers, but the costs associated with a top-of-rack switch and cabling are high. To solve these issues, 10GBase-T is introduced. It offers the most flexibility, and opens the door for cost-effective migration to 10GbE throughout the data center. The following part will give a brief introduction of 10GBase-T.

Overview of 10GBase-T

Defined by IEEE 802.3, 10GBase-T, which was released in 2006, is the version of Base-T (commonly referred to as “twisted pair” Ethernet) networking standard to achieve 10G data transmission over cat5, cat6a or higher balanced twisted pair copper cabling for a maximum reach of 100 meters. Important for backward compatibility, 10GBase-T uses the same RJ45 physical interface found in all existing Base-T networks. Besides, 10GBase-T preserves the user experience and the training investment that IT organizations have already made through multiple generations of Base-T use. The following image shows the cat6a 10GBase-T patch cable.

Unique Advantages of 10GBase-T

With various 10G media options available on the market, 10GBase-T has more unique advantages, making it a preferable choice for 10G Ethernet network. The following part lists some advantages of 10GBase-T:

Reach

Of the copper 10G Ethernet options, 10GBase-T has the greatest reach. 10GBase-T can operate at distances up to 100 m over cat6a cable or better cabling, which gives IT managers a far greater level of flexibility in connecting devices in the data center and accommodating top-of-rack, middle-of-row, or end-of-row network topologies.

Autonegotiation

Easy upgrade of 10GBase-T can be performed one end at a time, due to the autonegotiation feature. Autonegotiation enables 10GBase-T to be backward compatible with previous versions of the Base-T equipment. When a 10GBase-T port is connected to another Base-T port, they will communicate with each other and establish the fastest link that both ports can utilize. This flexibility eases installations in networks that already have Base-T switches and servers.

Saving Power

Early 10GBase-T products were relatively inefficient in terms of power use with first-generation, single-port adapters, consuming nearly 25 watt. However, the design enhancement and advanced production process make 10GBase-T more power-efficient (latest 10GBase-T adapters require less than 6 w per port). Standalone 10GBase-T PHYs have seen similar improvements in power utilization, resulting in greater port density for 10GBase-T switches. Many of these PHYs also incorporate a short-reach mode that can reduce power consumption down to 2.5 w for links of 30 m or less (as specified in the IEEE 802.3an standard).

Low Cost

As power consumption has dropped dramatically over the past years, the cost of 10GBase-T has followed a similar downward curve. The first-generation 10GBase-adapters cost $1000 per port, but the newest generation costs less than three hundreds of dollars. Besides, by using 10GBase-T connections, users will see a significant savings over the purchase of more expensive SFP+ DAC and fiber optic adapters, which cost several hundred dollars per adapter, and will be able to free up an I/O slot in the server.

The Future of 10GBase-T

Many industries foresee broad deployment of 10GbE in the form of 10GBase-T. According to the data reported by professionals, in 2010 SFP+ represented 34% of the 10GbE physical media in data centers. This percentage is projected to continue to rise through 2013 to 58%, with large deployments in IP data centers and for high performance computing. 10GBase-T will grow from only one percent of physical media in 2010 to 17% in 2013 and eventually become the predominant media choice with 61% of 10GbE deployments in 2016. There is no doubt that the future of 10GBase-T is really broad.

Conclusion

10G Ethernet has become a necessity both in the data center and in the campus LAN. 10GBase-T is the right option for most of the intra-building 10G links, since it provides a lower cost & power consumption, better backward compatibility and longer reach solution than the other optics. FS.COM provides a wide range of 10GBase-T products, such as cat5e cable, cat6a cable and cat7 cable. Besides, we also have various SFP+ optics in stock, including SFP+ transceivers (like SFP-10G-LR-S) and SFP+ cables (like SFP+ DAC). If you have any need, please visit FS.COM.

Cat5e VS Cat6 Cable – Which One Will You Choose?

With low cost, easy operation and great flexibility, twisted pair cables are widely used in telephone communications and modern Ethernet networks. Nowadays, there are many categories of twisted pair cables available on the market, such as cat3 cable, cat5/cat5e cable, cat6/cat 6a cable, and cat7 cable, etc. Today, I’d like to give a brief but complete discussion about two common categories—cat5e and cat6, which are so similar to each other that the general public may feel confused to know which cable is suitable for their tasks.

What Is Cat5e Cable?

Cat5e is an enhanced specification of the cat5 standard which was introduced to the market in early 2001. While similar to cat5 cable in appearance, cat5e cable introduces some new links in the equation. For one thing, cat5e cable uses four pairs of copper wire rather than the two that cat5 cable relies on. In addition, the wire pairs are twisted more tightly to eliminate crosstalk. Due to its internal upgrades, including faster transmission rate and higher bandwidth, cat5e cable has become the most common type of cabling found in modern homes and offices for Ethernet purposes. The following picture shows Cat5e cable.

What Is Cat6 Cable?

Only a year after cat5e was introduced, a new standard—cat6 was born. The cat6 standard improved upon the cat5e by increasing frequency responses, tightening crosstalk specifications, and introducing more comprehensive crosstalk specifications. Usually, cat6 cable (shown in the picture below) consists of four unshielded twisted pairs (UTP) terminated with RJ45 connectors, which is often used for 10Base-T (Ethernet), 100Base-TX (Fast Ethernet), 1000Base-T (Gigabit Ethernet) and 10GBase-T networks.

Differences Between Cat5e and Cat6 Cables

Transmission Speed

When we think about advances in cabling, transmission speed is the first thing that should be taken into consideration. As we mentioned previously, cat6 cable can be used to power 10GBase-T or 10G Ethernet, while the maximum speed that cat5e cable can support is 1GBase-T or 1G Ethernet. This is because cat6 cable performs up to 250 MHz, which is more than twice that of cat5e cable (100 MHz). 

Distance

Since cat5e and cat6 are made of copper wires, both of them are only available for short distance data transmission. If the cable is used for lower data rate transfer, both cat5e and cat6 cable can support the length of up to 100 m. However, when the data rate achieves the maximum speed, cat5e cable can reach 50 m, while cat6 cable can only reach 37 m.

Cost

In general, cat6 cables are 10 to 20% more expensive than cat5e cables. However, cables are comparatively cheap which makes the cost differences between cat5e and cat6 cables come to be very small portion of the total network budget. Besides, the speed boost offered by cat6 cables usually makes the price premium worthwhile, especially in long run transmission.

Reliability

When installing a network, many users may concern whether there will be electrical interference that can negatively influence the performance of their network. Compared with cat5e cable, cat6 cable has improved reliability that it can deter signal interference from affecting your network. You’ll be able to have a longer and more reliable period of uptime, regardless of how close you are to other network connections in your area. The following table shows some differences between cat5e and cat6 cables.

Conclusion

Cat5e and cat6 cables are two commonly used categories of twisted pair cables. They are different from supporting distance, transmission speed, cost, and reliability. After reading this post, hope you can choose the right one for your project. If you need cat5e, cat6 or other types of twisted pair cables, FS.COM is a good place to go. Besides these copper cables, we also supply a wide range of fiber patch cables with different connectors, such as SC, FC and LC connector. For more information, please visit FS.COM.

OTDR – Making it Easier to Test Optical Fiber Cabling Faults

Communication networks never go slower, never get simpler, and never stay the same. Likewise, certification testing for fiber-optic cabling has also changed. Various test equipment and enhanced testing regiments are manufactured by many vendors to ensure that cabling can support the new demands placed on networks. Among them, OTDR (shown in the following picture) is a new generation of fiber test equipment, which can make it easier to ensure consistent quality in an optical fiber. I’d like to introduce this new testing tool for you in the following part.

What Is OTDR?

OTDR, also called as optical time domain reflectometer, is an optoelectronic instrument which is basically used to identify and analyze reflective and non-reflective events that cause disturbance in an optical fiber link. OTDR are most effective when testing long cables (more than approximately 250 meters or 800 feet) or cable plants with splices. The data that OTDR produces is typically used to create a picture called as a trace or signature, which can be used for troubleshooting, since it shows where breaks are in fiber, when the trace or signature is compared to installation document. Using OTDR, you can easily confirm the quality of fibers and find where network trouble arises. There are various of OTDR available with different fiber types (like single-mode fiber) and wavelengths (such as 1310 nm, 1550 nm and 1625 nm). The image below shows the working principle of OTDR.

Working Principle of OTDR

OTDR uses the effect of rayleigh scattering and fresnel reflection to measure the characteristics of an optical fiber. In essence, it takes a snapshot of the fiber’s optical characteristics (the trace of length vs returned signal level) by sending high-powered pulse into one end of the fiber and measuring the light scattered back toward the instrument.

As we mentioned above, the trace, which can be analyzed on the spot, printed out immediately for documentation of the system, or saved to a computer for later analysis and comparison, is referred by trained operator to locate the end of the fiber, the location and loss of splices, and the overall loss of the fiber.

What can OTDR Be Used for?

OTDR is widely used in many phases of a fiber system’s life, from the construction, to maintenance, to fault locating and restoration. The following part lists some aspects that it can be utilized:

• Locating fiber cable breaks or cuts. OTDR can be used to predict the distance (in meters from the source) where the optical fiber cable has been disconnected.
• Measuring reflectance or optical return loss (ORL) of connectors and mechanical splices for CATV, SONET, and other analog or high-speed digital systems where reflections must be kept down.
• Identifying dissimilar and mismatched fibers (for example, 50 micron fiber and 62.5 micron fiber) that are connected together affecting the intensity of the light signal.
• Spotting usage of fiber patch cords with a different/incorrect core size that affects signal strength.
• Detecting the gradual or sudden degradation of fiber by making comparisons to previously-documented fiber tests.

Using Tips for OTDR Tester

When using an OTDR, there are a few tips that will make testing easier and more understandable:

• Always using a long launch cable, which allows the OTDR to settle down after the initial pulse and provides a reference cable for testing the first connector on the cable.
• Always start with the OTDR set for the shortest pulse width for best resolution and a range at least twice the length of the cable you are testing.
• Make initial trace and see how you need to change the parameters to get better results.

Conclusion

OTDR is an easier solution to test or identify faults in an installed fiber optic cable network as well as certify new fiber optic cable installation. This text has provided you with some basic information about OTDR tester and tell you several helpful tips for using OTDR tester. Besides OTDR that offered in fiberstore, there are various other types of optical testers, such as VSL (visual fault locator), ADSL tester, optical power meter, and so on. Each tester has unique functions and is used in different applications. If you want to know more information, please visit FS.COM.

Things You Should Know About UPC and APC

Whenever we install a connector on the end of fiber, loss will be incurred. Some of this light loss is reflected directly back down the fiber towards the light source which can damage the laser light sources and disrupt the transmitted signal. To reduce back reflection, we can polish connector ferrules to different finishes. Typically, there are two ferrule polish types widely used in fiber optic connectors—UPC and APC (the following image shows a SC APC fiber patch cord). What do UPC and APC stand for? What are the differences between them? And which one is the better solution to your network? The following part will solve these questions one by one.

What Is UPC?

UPC or ultra physical contact is an extended PC (physical contact) polish which results in a better surface finish (as shown in the image below). The rounded finish created during the polishing process allows fibers to touch on a high point near the fiber core where light travels. Offering -55dB return loss, UPC connector relies on machine polishing to deliver low optical return loss characteristics, making it acceptable in Ethernet network equipment such as serial services, media converters and fiber switches. (Tips: when using UPC connectors, make sure your laser’s specifications can handle the return loss that your UPC connector will generate.)

What Is APC?

APC, also named as angled physical contact (shown in the picture), is another style of ferrule polish. Its ferrule is polished with an 8-degree angle that end-face brings the fibers tighter and reflects light at an angle into the cladding instead of reflecting it directly to the light source, which causes its optical return loss to be -60dB or higher, making it a better-performance connector. APC connector handles multi-play systems which are mostly employed in radio frequency (RF) applications, like CATV or distribution antenna systems. It is also available in optical passive applications, such as PON networks architectures or passive optical LANs.

Differences Between UPC and APC

• Color Codes A simple way to distinguish UPC and APC is the color codes of the surface. In general, UPC connector is easily identifiable by their blue color on the connector boot, while the APC connector is green.
• Endface Geometry A UPC polish results in a dome-shaped endface that aids in optimizing the connections between two jacketed fibers, while the endface on an APC connector is polished at an eight-degree angle, which reduces the amount of light reflected between the two connected fibers.
• Return Loss The more significant performance characteristic between APC and UPC connectors is their return loss (or the amount of light reflected back to the original source). Return loss is a measurement of the light reflected back to the source at an optical interface. The higher the return loss, the better the performance. Generally, UPC connector is required -55dB or higher, while the APC is -65dB or higher.
• Insertion Loss Insertion loss is different from return loss, which refers to the measurement for the amount of optical power loss through a mated pair. The connector insertion loss can be used with the cable length loss to determine the allowable loss budget for an installed link. Insertion loss of APC and UPC should be less than -0.3dB, and the lower the insertion loss, the better the performance. Achieving low insertion is typically easier with UPC connector due to less air gap than APC connector. However, manufacturing techniques have improved significantly to create more precise angles on APC connector and bring insertion loss down closer to that of UPC connector.

Choosing a UPC or an APC?

Choosing the right connector for a network depends on many aspects, such as the network design, the performance of the connector itself, and installation budget, etc. Through the information we have discussed above, there is no doubt that APC has better performance than UPC. But, UPC connector will cost less than APC connector. Besides, when applications are sensitive to return loss than others, for example, FTTX (fiber to the x), passive optical network (PON), and wavelength division multiplexing (WDM), APC connector will be more preferable than UPC connector. But if you have limited cost budget and not ask for higher-quality system, UPC connector can be chose.

Summary

When choosing fiber patch cable jumpers, it is essential to take UPC and APC into consideration. Both of them can reduce back reflection and damage to the laser source. And after reading this passage, hope you can choose the appropriate one for you network application.