Knowledge About GPON SFP Transceivers

by Fiber-MART.COM

GPON stands for Gigabit Passive Optical Network. GPON is one of the key technologies that are being used in fiber-based (FTTx) access networks, including fiber to the home (FTTH), fiber to the business (FTTB), fiber to the curb (FTTC), etc. GPON system contains two main active transmission components, namely optical line termination (OLT) and optical network termination (ONT) or optical network unit (ONU). Modern OLT and ONT/ONU use compact fiber optic modules to achieve the triple-play GPON services. These modules are known as GPON SFP transceivers. This post will give a comprehensive introduction to GPON SFP modules.

 

What Is GPON SFP?

GPON SFP is one type of gigabit optical transceivers that are used in GPON system, which is compliant with ITU-T G.984.2 standard. It is a bidirectional module that has SC receptacle and works over simplex single-mode fiber optic cable. A GPON SFP module transmits and receives signals of different wavelengths between the OLT at the Central Office side and the ONT at the end users side. GPON SFPs utilize both the upstream data and downstream data by means of Optical Wavelength Division Multiplexing (WDM).

 

GPON SFP: Class B+ vs. Class C+

GPON SFP transceivers are categorized into GPON OLT SFP and GPON ONT SFP or GPON ONU SFP depending on the devices they are used in. And there are Class B+ GPON SFP and Class C+ GPON SFP. The major differences between them are the transmit power and the receive sensitivity. The table below lists the Tx power and Rx sensitivity of Class B+ GPON SFP and Class C+ GPON SFP.

 

By using Class B+ or Class C+ GPON OLT SFP, it can support up to 32 or 64 ONTs at customer premises respectively. And a C+ OLT SFP can be used with B+ ONT SFP as long as the loss budget of the link is appropriate.

 

How’s the GPON SFP Different From Conventional BiDi SFP?

Although GPON SFP belongs to the gigabit BiDi SFP family, it differs from “normal” BiDi SFPs in some aspects. Here’s a comparison between GPON SFP transceiver and conventional BiDi SFP transceiver.

 

Signal Transmission Mode

In terms of conventional gigabit BiDi SFP transceivers that are mainly used in backbone network, the optical transmission mode is point to point (P2P), i.e., they must be used in matched pair. A BiDi usually has LC receptacle instead of SC receptacle. Here’s an illustration of P2P transmission mode.

 

The transmission mode of GPON SFP is point to multi-point (P2MP). One GPON OLT SFP at the Central Office communicates with multiple GPON ONT SFPs with the help of fiber optic splitters. This is why we usually see a GPON infrastructure is in a tree shape or a tee shape.

 

Transmission Distance

The transmission distance of conventional gigabit BiDi SFP can be up to 160 km over single-mode fiber cable when using 1590nm/1510nm and 1510nm/1590nm wavelengths. GPON OLT and ONT/ ONU SFP transceivers support a transmission distance up to 20 km with 1490nm/1310nm and 1310nm/1490nm wavelengths.

 

Benefits of Using GPON SFP

Using GPON SFP is considered a more convenient and cost-effective solution for the end customers. And it also reduces the devices that need to be provided by the Internet service provider (ISP). Before the GPON ONT SFP was released and used in GPON networks, the ISP usually needs to install at least an optical modem (a type of ONT with a fiber optic port) and an IP access router, and a Set-Top-Box or video recorder might also be needed if IPTV services are required. The separation of different devices inevitably increased the cost for GPON services.

 

The newly used GPON SFP is in smaller size and integrates the triple-play services. It has lower consumption as well. The ISP provides a GPON ONT SFP to the customer. This module is usually installed in the hub/router handed to the customer by the ISP. The customer is also able to unplug the fiber optic patch cable and the GPON ONT SFP from the ISP’s hub/router, and then plug them in his own router/switch that is white-listed by the ISP.

 

Conclusion

GPON SFP transceivers are typically used in the two main active transmission components OLT and ONT/ONU in GPON optical networks. They are essential in keeping the high-bandwidth communication between the service provider and the end users over a distance up to 20 km. GPON SFPs are classified into Class B+ and Class C+ and the main differences are their Tx power and Rx sensitivity. This module has simplified the implementation of GPON services. It benefits both the service providers and the end users to some degree.

Global Optical Transceiver Market: Striding to 200G and 400G

by Fiber-MART.COM

The demand for higher Ethernet speed, couple with the prevalence of Cloud computing, Internet of Things and virtual data center, has driven the prosperity of optical transceiver market. Optical transceivers, direct attach cables (DACs) and active optical cables (AOCs) have evolved dramatically to catch leading edge broadband network capacity. The past decades have witnessed massive adoption of optical transceivers with data rates ranging from 1G, 10/25G to 40/100G, while higher-speed 200G or even data center 400G is just on the horizon. The sales of optical components grows steadily and is expected to continue in the years to come.

 

10G, 25G, 40G and 100G: Seeing Broad Adoption in Data Center 

As network gets faster and virtualization gradually becomes the norm, data center is undergoing a major transformation. The trend emerges in the industry signifies a migration toward higher speed transceivers and better service. These high-bandwidth transceivers are driving revenue growth which suggests a strong market. The global optical transceiver market is anticipated to reach to $9.9 billion by 2020, driven by the widespread use of 10/25 Gbps, 40 Gbps and 100 Gbps, and with the biggest sales forecasted for 25G and 100G ports. The imminent 200 Gbps and 400 Gbps optical transceivers also poise to hold a fraction of the market share.

 

10G Transceiver: Moving to the Edge

Initially offered in the early 2000s, 10 Gigabit Ethernet has matured now to become a commonplace in data center. 10G server connections reached majority of new shipments and have outpaced 1G connection in 2015. Basically the 10G Ethernet is stacked to move to 40G and 100G at the access layer, following the upgrade path of 10G-40G-100G, which, however, will quadruple the cabling complexity, power consumption and overall cost. And this will be exacerbated when aggregating into 100G (10×10G) interface.

 

25G Transceiver: Pave the Road for 100G

So there comes the game changer: 25G Ethernet for better economics and efficiency. 25 Gigabit Ethernet makes the road to 100G smoother with reduced cost, lower power consumption and less cabling complexity. SFP28 optical transceiver is designed for use in 25G Ethernet, delivering 2.5 times higher speed per lane at lower power. 25G SFP28 can be viewed as the enhanced version of 10G SFP+ transceiver, utilizing the same form factor but running at 25 Gb/s instead of 10 Gb/s. Besides, SFP28 25G is back compatible with SFP+ so it will work sufficiently on SFP+ ports. By the year of 2019, the price of a 25G SFP28 will be almost the same as a 10G SFP+. So you will be saving a great bunch of money if choosing to move to 25G. Some users even plan to skip 10G and directly deploy 25G Ethernet for better scaling to 50G and 100G.

 

40G Transceiver: Affordable for Mass Deployment

Obviously, 10GbE is no longer fast enough for data centers handling large-scale applications, so 40G is designed to alleviate bottlenecks in the access layer . When firstly planning to scale to 40G, the cost is extremely high that makes the implement of 40G technology difficult. Luckily, we’ve seen significant cost reduction of 40G optics in the past 2 years: QSFP-40G-SR offered by fiber-mart.COM is $49 only. The price drop accelerates 40G transceivers adoption in aggregation links, or in access links to connect servers. For scaling to“spine-leaf” architecture, 40G switches can be used as spine switch with the 40G QSFP+ ports breaking out into 4 10G SFP+ ports to support 10G server uplinks. 40G port revenue has peaked in 2016 and will now decline in favor of 25G and 50G ports.

 

100G Transceiver: Ramping up in Data Center

Currently 100G are the fastest Ethernet connections in broad adoption, which is growing sustainably. And the optical transceiver market indicates that 100G QSFP28 module price will continue to drop, making the cost difference between 40G and 100G even small. For example, fiber-mart.COM offers great cost reduction on 100G transceivers: only $199 for QSFP28 100G-SR. Moreover, 100G switch port shipments will outnumber 40G switch port shipments in 2018—as 25G server and 100G switch became commonplace in most hyperscale data centers that replaces previous 10G servers and 40G switches. Vendors of 100G QSFP28 transceiver will continue to grow the product and push the limits of its versatility.

 

200G and 400G – New Connection Speed Hits Data Center

Another foreseeable trend in interconnect market is the phase out of low speed transceivers in the core of networks and in data centers. So here comes the major shift from 10G and under to 40/100G and higher. New developments with QSFP28 technology in 2018 also will pave the way for the 200G and 400G QSFP-DD: next-generation 200G and data center 400G Ethernet will deploy starting in 2018, and become mainstream by 2019-2020. On the whole, optical transceiver market is evolving to higher speed, more reduced power consumption and smaller form factor. Let’s take a look at these future-proofing optical transceivers.

 

DAC and AOC: Lower Cost Stimulate Popularity

DACs (direct attach copper cables) and AOCs (active optical cable), with their inherent advantage of enhanced signal integrity and superior flexibility, have become the preferred, cost-effective interconnect for high-speed links at 10G, 25G, 40G and 100G for about all applications in hyperscale and enterprises, and is likely to be used for 200G and 400G as well. DAC and AOC provide improved speed and cost efficiency, they are witnessing tremendous growth in data interconnect market. 2017 has witnessed shipment over 100k direct attach copper cables for 100Gb/s networks in hyperscale data centers, and this is anticipated to continue in 2018. While the global market for AOC is projected to surpass $2 billion by 2020, the sales will keep surging in the years to come.

 

Conclusion

Data demand will continue to skyrocket. As the vast increases in Internet traffic are pushing optical transceiver market to shift, we can still expect deployment of 10/25/40/100 Gigabit Ethernet (GbE) optics in mega data centers to spur market growth in 2018. While the lower-cost and power-efficient DACs and AOCs are yielding significant growth in short-distance high speed interconnect. So just stay tuned and embrace the significant opportunities lie ahead for optical transceiver market.

Introduction of Fiber Optic Splice Closure

by Fiber-MART.COM

Fiber optic splice closure is the equipment used to offer room for fusion splicing optical fibers. It also provides protection for fused fiber joint point and fiber cables. There are mainly two types of closures: vertical type and horizontal type. A large variety of fiber splice closures are designed for different applications, such as aerial, duct fiber cables and direct burial. Generally speaking, they are usually used in outdoor environment, even underwater.

 

1. Horizontal type splice closures look like flat or cylindrical case. They provide space and protection for optical cable splicing and joint. They can be mounted aerial, buried, or for underground applications. Horizontal types are used more often than vertical type (dome type) closures. Most horizontal fiber closure can accommodate hundreds of fiber connections. They are designed to be waterproof and dust proof. They can be used in temperature ranging from -40A degree to 85A degree and can accommodate up to 106 kpa pressure. the cases are usually made of high tensile construction plastic.

 

2. Vertical type of fiber optic splice closures looks like a dome, thus they are also called dome types. They meet the same specification as the horizontal types. They are designed for buried applications.

 

Applications splice closures provide room for splicing Outdoor Fiber Optic Cable together. fiber splice trays are needed too. they provide the perfect protection for outside plant fiber cable joints. fiber splice closures accept both ribbon and round fiber cables. Each type (ribbon or round cable) fits respective requirement of different fiber splicing counts. They are widely used in optic telecommunication systems.

 

Fiber Optic Splice closure Installation Steps

 

1.Fiber optic splice closure kit usually includes: end plate, splice tray organizer, fiber splice tray, cover, cable grommets, grommet retainer, mounting bracket and misc. hardware.

 

2. Fiber Cable Sheath Preparation

 

1)Expose the rip cord. This step involves marking the location with a tape marker, ring-cutting the outer jacket shaving off the outer jacket to expose the rip cord.

 

2)Remove the outer sheath. This step involves making a longitudinal slit down the outer sheath,peeling off the outer jacket and corrugated metal, and cutting the rip cord flush with the end of the corrugated metal.

 

3)Rewove the inner jacket. This step involves using the rip cord under the inner jacket to slit it, cutting aramid yarns, cutting central strength member, and cleaning the filling compound.

 

3. Bonding and Grounding Hardware Installation This step involves sliding the cable clamp over sheath, sliding the bond shoe under the corrugated metal, placing the bond plate over the bond shoe ans securing the sheath grip.

 

4. Assembly of Cables to Closure The preferable location for the two main cables is in the lower end plate port. If a third or fourth cable is required, it is easier to install it in the upper end plate port as a branch cable. This fiber optic splice closure is designed for two cables in each of its two ports. If only one cable will be installed in a port, the provided rubber grommet plug is used to substitute for the second cable.

 

1) Install Cables to End Plate. this step involves unscrewing knob and removing grommet retainer, positioning the end plate assembly, attaching the sheath grip to dielectric cables, sliding cables and sheath grip through, and securing sheath grip to backbone.

 

2) Grommet Installation and External Grounding. This step involves applying Bsealant, pushing the grommets into the end plate port, and applying more B-Sealant.

 

3) Fiber unit Preparation and Distribution Organizer Installation. This step involves removing more loose tubes,separating each cable’s loose tube into two groups, positioning the distribution organizer, securing the loose tubes.

 

4) Splice Tray Installation. This step involves placing the splice tray, fastening the end of the splice tray to the organizer, and installing cables, grommets and external ground.

 

5) Optical Fiber Splicing. This step involves splicing holder placing, fiber splicing and fastening the splice holder lid.

 

5.Fiber Optic Splice Closure Cover Installation.

 

6.Closure mounting

 

7.Reentry

DWDM Solutions for Metropolitan Area Network

by Fiber-MART.COM

Today’s services like voice, video and data networks are getting complex and growing tremendous, as well as requiring more bandwidth and faster transmission rates over farther distances. All these cause ferocious competition in the service provider market. And it’s impossible to charge more for the ever-increasing access speed, which resulted in the deployment of DWDM (dense wavelength-division multiplexing) technology in the long-haul transoceanic and terrestrial networks. As DWDM equipment becomes more economical and cost-effective, to deploy them in the metropolitan area network (MAN) is necessary.

 

Why DWDM is Necessary for MANs?

When it comes to DWDM for MANs, many people may ask “Why is DWDM suddenly so popular for MAN applications?” Considering both the DWDM technology and MAN, this question can be discussed from two aspects.

 

The first one is the situation of MAN at present. The practical demands for bandwidth and speed of users affect service providers in the MANs. They have to face problems such as service diversity, bandwidth scalability and fiber exhaustion. Bandwidth scalability deals with the capability of the fiber to carry traffic at exponentially greater speeds. Only by that, the bandwidth provided by service managers may meet the requirements. As for fiber exhaustion, adding more fiber cables may be helpful, but it will cost more and need a long time to finish.

 

Another one is the advantages of deployment DWDM technology. DWDM technology was first deployed on long-haul routes in a time of fiber scarcity. And it finds applications mainly in ultra-high bandwidth long haul as well as in ultra-high-speed metropolitan or inner-city networks, and at the edge of other networks like SONET, SDH and IP. As the ubiquitous deployment of DWDM network and the passive or active DWDM equipment, DWDM technology is expected to be the low-cost solution in MANs and many access-type networks like FTTH and FTTD.

 

Essential DWDM Equipment Used in MAN

As we know, in DWDM networks, multiple wavelengths of light are multiplexed into one single fiber. Therefore, DWDW equipment should be capable of combing or removing signals. Here are three main types of DWDM equipment used in MAN.

 

DWDM Multiplexer and Demultiplexer (DWDM Mux/Demux)

DWDM Mux/Demux modules deliver the benefits of DWDM technology in a fully passive solution. They provide a good solution for long-distance links where wavelengths are packed tightly together over the C-band range of wavelengths, up to 48 wavelengths in 100GHz grid (0.8nm) and 96 wavelengths in 50GHz grid (0.4nm). Usually the common configuration of DWDM Mux/Demux is from 8 channels to 96 channels.

 

DWDM Optical Add/Drop Multiplexer (DWDM OADM)

In order to connect different sites via individual wavelengths, a DWDM system needs to have the capability to add and drop services at distinct locations. That’s why DWDM OADM is needed. OADM can pass-through, remove or add the channels as required. It’s a pass type of DWDM equipment. And the optical losses are different for the add, drop, and pass-through channels.

 

DWDM Erbium-Doped Fiber Amplifier (DWDM EDFA)

Since DWDM network is designed for long runs transmission, the optical power of signals will attenuate with the distances increase. To ensure the quality of signals, DWDM EDFA are used according to the power budget between the transmitter and receiver. Usually based on the used places, there are three common types of fiber amplifiers: booster, in-line amplifier and pre-amplifier. And the gain also can be customized based on specific needs.

 

fiber-mart.COM DWDM Solution for Metropolitan Area Network

Today’s explosion in data traffic, fueled in large part by the growth of the Internet, has caused rapid depletion of available fiber bandwidth in the metropolitan area. The bandwidth bottleneck is now that of the MANs, where capacity has not increased as greatly as the long-haul networks. To meet the demand for long runs transmission in MANs, fiber-mart.COM provides FMT multi-service transport platform for flexible and high density DWDM networking solution. All DWDM equipment like EDFA, OEO, DCM and OLP (optical line protection) come in small plug-in cards, enabling easy installation and management during network deployment. For more details about this DWDM solution, please read this article: Extend DWDM Network Transmission Distance With Multi-Service Transport Platform

How to Test Fiber Optic Cables by OTDR

by Fiber-MART.COM

OTDR, full name of which is optical time-domain reflectometer is one of the most popular method of testing the light loss in the cable plant. In most circumstance, it also indicate an fiber optic testing instrument to characterized the optical fibers. OTDRs are always used on OSP cables to verify splicing loss or locating damages to the fiber optic cables. Due to the decline in the OTDR price over recent years, it is more and more applied by technicians for the system installation process.

 

OTDR testing

 

OTDR uses backscattered light of the fiber to imply loss, which is an indirect measurement of the fiber. OTDR works by sending a high power laser light source pulse down the fiber and looking for return signals from backscattered light in the fiber itself or reflected light from connectors or splice interface. OTDR testing requires a launch cable for the instrument to settle down after reflections from the high powered test pulse overloads the instrument. OTDRs can either use one launch cable or a launch cable with a receive cable, the tester result of each is also different.

 

Test With Launch Cable Only

A long lauch cable allows the OTDR to settle down after the initial pulse and provides a reference cable for testing the first connector on the cable. When testing with an OTDR using only the launch cable, the trace will show the launch cable, the connection to the cable under test with a peak from the reflectance from the connection, the under testing cable and likely a reflection from the far end if it is terminated or cleaved. Most terminations will show reflectance that helps identify the ends of the cable.

 

By this method, it can not test the connector on the far end of the under testing cable since it is not connected to another connector, and connection to a reference connector is necessary to make a connection loss measurement.

 

Test With Launch And Receive Cable

By placing a receive cable at the far end of the under testing cable, the OTDR can measure the loss of all factors along the cable plant no matter the connector, the fiber of cables, and other connections or splices in the cable under test. Most OTDRs have a least squares test method that can substract out the cable included in the measurement of every single connector, but keep in mind, this may not workable when the tested cable is with two end.

 

During the process you should always keep in mind to 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 an initial trace and see how you need to change the parameters to get better results.

 

OTDRs can used to detect almost any problems in the cable plant caused during the installation. If the fiber of the cable is broken, or if any excessive stress is placed on the cable, it will show up the end of the fire much shorter than the cable or a high loss splice at the problem locations.

 

Except OTDR testing, the source and optical power meter method is another measurement which will test the loss of the fiber optic cable plant directly, The source and meter duplicate the transmitter and receiver of the fiber optic transmission link, so the measurement correlates well with actual system loss.

Cable Testers used in Network

by Fiber-MART.COM

What is a Cable Tester? A cable tester is an electronic device used to verify the electrical connections in a cable or other wired assembly. Sometimes we also call it Network Cable Tester, because it is usually used in LAN Network.

 

There are many different types of cable testers, each able to test a specific type of cable or wire (some may be able to test several different types of cables or wires). The cable tester can test whether a cable or wire is set up properly, connected to the appropriate source points, and if the communication strength between the source and destination is strong enough to serve its intended purpose. Here is an example of a cable tester made in fiber-mart.

 

Its model is PN-8108, a Multifunction Network Cable Tester. This tester is very easy to operate for prevent and solve cable installation problem. It can widely be used for a number of applications such as cable connection sequence, length, user jumper and cable connection continuity and determine any open circuit, short circuit, jumper or cross-talk interference.

 

For computers, one of the most common types of cable testers used is for testing Cat5, Cat5e, and Cat6 network cables. Because so many different types of data can be transmitted over a network cable, it is important that the network cable connects properly between the computer and server. It is also important to ensure the signal strength between computers and servers is adequate for transmitting data and that there is no interference from outside sources that could cause a loss of data or decrease in signal strength. A cable tester can test for these factors and help to ensure the network cables connections are correct and will work for the intended purpose.

 

fiber-mart supplies many kinds of LAN Network Cable Testers, which are a kind of convenient and comprehensive tools for network professionals. Network Cable Tester is always being used to test LAN Datacom and Telecom cables. Network Cable Line Tester can find all problems associated with testing such faults as opens, shorts, cable integrity and it also find cable length of individual cables or distance to a fault, and its powerful and user-friendly features enable network installers to accurately check pin configurations of various voice and data communication cables.

 

Except Network Cable Testers, fiber-mart also offers many kinds of fiber optic tester. There are OTDR Testers, ADSL Testers, CCTV Security Testers, and Telephone Line Testers here.

 

Telephone Line Tester is a new kind of line fault tester with safety and multi-functions capabilities. Besides the functions as a common Telephone Line Tester, it also has the functions of high voltage protection and dangerous voltage warning. Such a phone line tester is used for detecting either digital or analog phone systems as well as the line polarity. Telephone line testers are good for both personal and professional use. fiber-mart supplies some mini phone line testers and other general telephone line testers. The importance that you should know is they are the cheapest and best performance products in fiber optic network.

Crimping Tool Types And Operation

by Fiber-MART.COM

The crimping tool is used for creating a joint between two metal pieces or other materials with good malleability. The joint formed by crimping needs to be strong to ensure that the application works properly. Crimping tools are available in different types to support various types of applications. fiber-mart is a good crimping tools supplier.  We provide many types of crimping tools in all possible varieties so that the purchasers are able to make the right choice while being in our store.

 

For example, the structured cabling system lays stress on following the practices which will add elegance, discipline, method and reliability to cabling. The tools which are used in installation of a cabling system go a long way in and can sustain extensive use in the field. Modular Crimping Tool can be used to crimp RJ-45(related products: rj45 plug) and RJ-11 types of fiber connectors. It is a highly compact and rugged tool and is meant for continuous use in the field. The parallel action design maintains accurate.

 

Hand operated crimpers are the most frequently used of all crimping tool types. Most are designed in a basic plier pattern with one or a number of crimping points machined into their jaws. This type of tool is typically used to effect smaller crimps on steel cables, electrical connections and terminations, preinsulated lugs and ferrules, and RJ type plugs. The crimp points on hand crimpers are either half round compression or cup and tab crimp type designs. This type of crimper is generally used to crimp steel or copper ferrules or sleeves to join two lengths of steel or electrical cable.

 

Types of Crimping Tools

 

First and foremost, you must offer these them manufactured in different types. Different customers might come and ask for a specific type. learn about different types of tools used for crimping form the below list:

 

1.Cable tie tools are the crimping tools used to tighten the ties around the bundles of wires or cables.

2.Compression crimp tools are used for terminating twisted-pair modular plugs and coaxial compression connectors.

3.RJ45 crimp tools are used for crimping the wires of various connectors like RJ45, RJ-11, RJ-12 and so on.

4.Point to cup tools are used with round section crimp sleeves. Besides, there are cup to cup tools available in different varieties like standard duty tool, heavy duty tool and bench press tool.

 

Crimp Tool Operation

 

A crimping tool is an essential part of the crimping process, the other parts being the terminal and wire. Terminal size is largely universal and can accept many sizes of gauged wire, which can also vary widely within the same nominative value. As such, the crimp tool is a means of compressing the terminal to both the wire’s insulation (for positioning) and the wire’s brush (for conduction).

 

The quality of the tooling determines the quality of the crimp design. Common considerations include if the volume of crimping deserves an automated wire stripping and process machine, or if the application is better suited by an on-site, handheld crimping tool. Many tools will have two crimping cavities to properly roll the terminal’s crimps, and possibly more if there are two conductors in the wire. Some crimp tools will feature several gauge sizes and possibly a stripper to enhance the crimper’s utility. Crimp tools may also feature interchangeable dies. Die-less crimpers are meant for general applications.

 

fiber-mart supplies a wide variety of specialized cable crimping tool, modular crimping tool, network cables crimpers which are all at very competitive price to help you get the job done right. For more information, please contact our sales representative right now.