Which One to Choose for FTTH Drop Cable Installation, Splices or Connectors?

When deploying an FTTH network, you must choose the right drop cable interconnect solution. This is for both ends of the drop cable—the distribution point and the home's optical network terminal (ONT) or network interface device (NID). There are two basic options: splices (permanent joint) and connectors (easily mated and unmated by hand). They both are widely used at the distribution point, but at the ONT/NID, a field-terminated connector or a spliced-on factory-terminated connector is used. How to choose? This post will discuss these two interconnect solutions for FTTH drop cables and their own pros and cons.

Splices: Pros and Cons

Pros: Splices can make sure excellent optical performance. Splicing can eliminate the possibility that the interconnection point becomes dirty or damaged. A dirty or damaged point may potentially compromise signal integrity, as may happen to a connector end face when it is handled while unmated. Contaminants will cause high optical loss or even permanently damage to the connector end face. And splice enables a transition from 250µm drop cable to jacketed cable.

Cons: Splice lacks operational flexibility. To reconfigure a drop cable at the distribution point, one splice must be removed, fibers rearranged, and new fibers spliced, which requires the technician to carry special splicing tools for simple subscriber changes. During this time, other customers' service may be disrupted by the fiber-handling process. 250µm fiber cable is usually used at the distribution point, which is easily bent and then causes high optical loss or even break the fiber. Besides, if a splice is used at the ONT, a tray is needed to hold and protect the splice, which increases the ONT size and potentially the cost.

Connectors: Pros and Cons

Pros: Connectors can be mated and unmated repeatedly, which makes them provide greater network flexibility. For example, to connect or disconnect an SC to ST fiber cable connection, without any tools, a technician can just easily plug or pull out the SC connector and ST connector on two ends. Connectors can also provide access points for networking testing.

Cons: Material cost is connectors' the most obvious downside. They cost more than splices, although network rearrangement with connectors is much cheaper. Providers need to weigh connectors' material cost and their potential for contamination and damage against the great flexibility and low network management expense.

Choose the Right Splice

Splice is appropriate for drops where there is no need for future fiber rearrangement, typically in a greenfield or new construction application where all of the drop cables could be easily installed during the living unit construction. Once the decision goes to splices, the type of splicing (fusion and mechanical) must be determined.

Fusion splicing has been the de facto standard for fiber feeder and distribution construction networks. Fusion splicer is used for FTTH drop splicing as it provides a high quality splice with low insertion loss and reflection. However, the initial capital expenditures, maintenance costs and slow installation speed of fusion splicing hinder its status as the preferred solution. Fusion splicing is suitable for companies which have invested in fusion splicing equipment and have no need to purchase additional splicing machines. Mechanical splices are successfully deployed around the world in FTTH installation, but not popular in United States because the index matching gel inside the splices can yellow or dry out, resulting in service failures. Great strides have been made in improving gel performance and longevity over the last 20 years.

Choose the Right Connector

Connectors could be used to connect different subscribers as needed for distribution points. It must be installed at the ONT and then offers flexibility both at the curb and at the home. Once the decision goes to connectors, factory-terminated connectors or field-terminated connectors must be decided.

Factory-terminated cables, such as LC to LC cable or SC to LC cable, which means the connectors you specify are pre-terminated for you, provide high-performance and reliable connections with low optical loss. By reducing installation time, factory termination keeps labor costs low. But factory-terminated cables are expensive compared to field-terminated alternatives. And they require a cable management system to store slack cable at the curb or in home. The installation of field-terminated connectors can be customized by using a reel of cable and connectors. Fuse-on connectors use the same technology as fusion splicing to provide the highest level of optical performance in a field-terminated connector. Mechanical connectors provide alternatives to fuse-on connectors for field installation of drop cables. Depending upon service provider requirements and living unit configurations, a hybrid solution of a field-terminated connector on one end of the drop cable and a factory-terminated connector on the other may be the optimal solution.

Summary

The drop cable interconnect solution is a key component of an FTTH network. Selecting the right connection option not only offers cost savings and efficient deployment but also provides reliable service for customers. Many FTTH drop cable installations have been field terminated on both ends of the cable with mechanical connectivity solutions.

What Affects the Optical Transmission Distance?

Optical network has now been more and more popular now, for it has several advantages, such as high speed, high bandwidth and high density. And fiber optic cables can support much longer distance than traditional copper cables (like twisted pair cables or coaxial cables). However, in practice, the distance that fiber optic cable can support is affected by many factors. Transmission distances of optical links vary from meters to hundreds of meters and kilometers, but optical signals may become weak over long distances. What affects the transmission distance? This article will talk about several factors that affect optical transmission distance.

Type of Fiber Optic Cable

Generally, the maximum transmission distance is limited by the dispersion in fiber optic cables. There are two types of dispersion that can affect the optical transmission distance—chromatic dispersion and modal dispersion. Chromatic dispersion is the spreading of signals over time resulting from different speeds of light rays. Modal dispersion represents the spreading of the signals over time resulting from different propagation modes.

For single-mode fiber optic cable transmission, it is chromatic dispersion that affects the transmission distance. The reason is that the core of a single-mode fiber optic cable is much smaller than that of a multimode optical cable, and only allows one mode of light to propagate. Single-mode optical cable can transmit signals over longer distance than multimode optical cable. Multimode optical cable transmission is largely affected by modal dispersion, because these optical signals cannot arrive simultaneously and there is a delay between the fastest and the slowest modes, which causes the dispersion and limits the performance of multimode fiber optic cables, as shown in the following picture.

Light Source of Fiber Optic Transceiver

Fiber optic cable is the path for the transmission of optical signals. However, most of the terminals are electronic based, so the conversions between electrical signals and optical signals are very necessary. And this process largely depends on fiber optic transceivers, which are commonly used in most of today's fiber optic networks. LED (light emitting diode) or laser diode inside are the light sources of fiber optic transceivers, which can also affect the transmission distance of a fiber optic link.

LED diode based transceivers can only support short distances and low data rate transmission. They cannot satisfy the increasing demand for higher data rates and longer transmission distances. For higher transmission data rates, laser diodes are used. Several commonly used laser sources in fiber optic transceivers are Fabry Perot (FP) laser, Distributed Feedback (DFB) laser and Vertical-Cavity Surface-Emitting (VCSEL) laser. For example, TRENDnet TEG-MGBSX SFP transceiver is a 1000BASE-SX SFP transceiver module with a VCSEL laser transmitter, which can support a data rate of 1.25Gbps and 550m transmission distance. The following table shows the main characteristics of these light sources.

Splices and Connectors

Splices or connectors are inevitable in many fiber optic systems. Signal losses can be caused when optical signals pass through each splice or connector. The amount of the loss depends on the types, quality and number of connectors and splices. For example, signal loss through an LC LC multimode duplex fiber cable may not be the same with an ST ST multimode duplex fiber cable.

Frequency of Transmission

As mentioned in the above table, different laser sources support different frequencies. The maximum distance an optical system can support is also affected by the frequency at which the signals are transmitted. Generally the higher the frequency is, the longer distance the optical system can support. Thus, choosing the right frequency to transmit optical signals is quite necessary.

Bandwidth

The bandwidth that fiber optic cable supports is another important factor that influences the transmission distance. As the bandwidth increases, the transmission distance usually decreases proportionally. For instance, a fiber that can support 100 MHz bandwidth at a distance of 5 kilometers will only be able to support 250 MHz at 2 kilometers and 500 MHz at 1 kilometer.

Summary

There are many factors that affect the optical transmission distance, such as the type of fiber optic cable, light source of fiber optic transceiver, splices and connectors, frequency of transmission, bandwidth that the network supports. All these factors need to be taken into consideration during the deployment of fiber optic networks to minimize the limitations on the transmission distance.

Why Choose 10GBASE-T for 10GbE Data Center Migration?

With the bandwidth migrating from 100M Ethernet to 1/10 Gigabit Ethernet (GbE), large enterprises have also been migrating their data center infrastructures accordingly. 10GbE technology has now been very mature and 10GbE in the data center is very common now. There are many interfaces options for 10GbE, such as SFP+ fiber, CX4, SFP+ direct attach copper (like HP J9281B SFP+ passive direct attach copper cable, or HP JG081C SFP+ passive direct attach copper cable), and 10GBASE-T. Among them, which one will you choose? Each one has its own advantages and disadvantages. In this post, we will talk about why choose 10GBASE-T in 10GbE data center migration.

Disadvantages of SFP+ in 10GbE Data Center

SFP+ has been adopted on Ethernet adapters and switches and supports both copper and fiber optic cables, which makes it a better solution than CX4. However, SFP+ optical transceiver (such as Cisco SFP-10G-LR-S 10GBASE-LR SFP+ transceiver) is not backward-compatible with the twisted-pair 1GbE broadly deployed throughout the data center. SFP+ connectors and their cabling were not compatible with the RJ-45 connectors used on 1GbE networks. Enterprise customers cannot just start adding SFP+ 10GbE to an existing RJ-45 1GbE infrastructure. New switches and new cables are required, which is a big chunk of change.

Advantages of 10GBASE-T in 10GbE Data Center

10GBASE-T is backward-compatible with 1000BASE-T, it can be deployed in the existing 1GbE switch infrastructures in the data centers that are cabled with CAT6, CAT6A or above cabling. As we know, 1GbE is still widely used in data center. Thus, 10GBASE-T is a great choice for gradual transition from 1GbE deployment to 10GbE. Other advantages of 10GBASE-T include:

Reach

Like all BASE-T implementations, 10GBASE-T works for lengths up to 100 meters, which gives IT managers a far-great level of flexibility in connecting devices in the data center. 10GBASE-T can accommodate either top of the rack, middle or end of the row network topologies, giving IT managers flexibility in server placement since it will work with the existing structured cabling systems.

Power

The challenge with 10GBASE-T is that even single-chip 10GBASE-T adapters consume a watt or two more than the SFP+ alternatives. More power consumption is not a good thing in the data center. However, the expected incremental costs in power over the life of a typical data center are far less than the amount of money saved from reduced cabling costs. Besides, with process improvements, chips improved from one generation to the next. The power and cost of the latest 10GBASE-T PHYs will be reduced greatly than before.

Reliability

Another challenge with 10GBASE-T is whether it could deliver the reliability and low bit-error rate of SFP+, or whether the high demands of FCoE could be met with 10GBASE-T. Cisco has announced that it had successfully qualified FCoE over 10GBASE-T and is supporting it on its newer switches that support 10GBASE-T in 2013.

Latency

10GBASE-T has a low latency range, from just over 2 microseconds to less than 4 microseconds. Latency for 10GBASE-T is more than 3 times lower than 1000BASE-T at larger packet sizes. Only the most latent sensitive applications such as HPC or high frequency trading systems would notice any latency.

Cost

When it comes to the cost, copper cables offer great savings. Typically, passive copper cables are two to five times less expensive than comparable lengths of fiber optic cables. In a 1,000-node cluster, with hundreds of required cables, that can translate into hundreds of thousands of dollars. Extending that into larger data centers, the savings can reach millions. Besides, copper cables do not consume power and because their thermal design requires less cooling, there are extensive savings on operating expenditures within the data center.

Conclusion

10GbE standards are very mature and reliable now. 10GBASE-T can save you a lot and at the same time provide you with easy cable installation. 10GBASE-T can also be backwards compatible with 1GbE networks, offering investment protection. Deployment of 10GBASE-T will simplify the networking transition by providing an easier path to migrate to 10GbE infrastructure in support of higher bandwidth needed for virtualized servers.

Introduction to Fiber Breakout Cable

When talking about direct attach cables, we may come across breakout cable, such as Cisco QSFP+ breakout cable. There are many kinds of breakout cables, and they are suitable for various applications. For example, a Cisco QSFP-4SFP10G-CU5M compatible QSFP+ to 4 SFP+ passive direct attach copper breakout cable, as shown below, connects to a 40G QSFP+ port of a Cisco switch on one end and to four 10G SFP+ ports of a Cisco switch on the other end, and is used for very short distances and offers a very cost-effective way to connect within racks and across adjacent racks. Other than copper breakout cable, there is also fiber breakout cable. What is fiber breakout cable? How much do you know about fiber breakout cable? In this post, a brief introduction to fiber breakout cable will be given.

What Is Fiber Breakout Cable?

Breakout-style fiber optic cable, also called fiber breakout cable or fiber fan-out cable, is an optical cable which contains several jacketed simplex optical fibers package together inside an outer jacket. It differs from a distribution-style cable, in which tight-buffered fibers are bundled together, with only the outer cable jacket of the cable protecting them. The design of breakout-style cable adds strength for ruggedized drops, however the cable is larger and more expensive than distribution-style cable. The structure of fiber breakout cable (shown as the figure below) ensures a long life. A fiber breakout cable consists of outer jacket, tap binder, breakout fiber assembly (tight-buffered fiber surrounded in aramid yarns and jacketed), strength member, and ripcord. For easier handling, it also features an easily strippable 900µm coating. Both the PVC and plenum cables are rated for fire safety.

Features of Fiber Breakout Cable

• The key purpose of fiber breakout cable is that one can "break out" several fibers at any location, routing other fibers elsewhere.
• Each numbered fiber sub unit is protected by a layer of aramid yarn and encased in a FRNC/LSNH jacket. The individual sub units are cabled and then jacketed with a flame resistant FRNC/LSNH compound. Each fiber uses either the tight buffer technology or semi-tight buffer technology for excellent fiber stripping.
• Each fiber of a breakout cable has its own jacket and aramid strength elements, so each fiber is extremely strong and rugged.
• Fiber breakout cable is available in a variety of designs that will accommodate the topology requirements found in rugged environments. Fiber counts from simplex to 256 are available.
• A tight buffer design is used along with individual strength members for each fiber. This permits direct fiber cable termination without using breakout kits or splice panels.
• Due to the increased strength of Kevlar members, fiber breakout cables are heavier and larger than the telecom types with equal fiber counts.
• A fiber breakout cable offers a rugged cable design for shorter network designs. This may include LANs, data communications, video systems, and process control environments.

Advantages of Fiber Breakout Cable

• Fiber breakout cable is extremely versatile and suitable for use in riser and plenum indoor applications. You can use it in backbone and horizontal runs.
• Each fiber is individually reinforced, so you can divide a breakout cable into individual fiber lines, which enables quick connector termination and eliminates the need for patch panels.
• Fiber breakout cable can be more economical because it requires much less labor to terminate. You may want to choose a cable that has more fibers than you actually need in case of breakage during termination or for future expansion.
• Fiber breakout cable offers advantages over standard patch cords because it eliminates the need for a fiber-optic ducting system.

Applications of Fiber Breakout Cable

Fiber breakout cables are typically used for indoor applications, between an optical distribution frame and an electronic equipment rack, or between two electronic equipment racks. These cables are particularly effective when equipment racks are distributed over a large area (for example several floors in a large building). The end of the breakout cable behaves like a standard single pigtail. The outer jacket of the cable can be stripped. Fiber breakout cables are used to carry optical fibers that will have direct termination to the equipment, rather than being connected to a patch panel. Covered with an outer jacket, these cables are ideal for routing in exposed trays or any application requiring an extra rugged cable that can be directly connected to the equipment. And they are also suitable for pre-terminated cable assemblies.

Conclusion

Fiber breakout cables are ideal for installations requiring an extremely rugged and reliable cable design where maximum mechanical and environmental protection are necessary. And fiber breakout cables have many obvious advantages, such as cost savings, direct termination to sub cable, which eliminates the need for patch panels and patch cords and reduces connector loss, and easy installation and high crush resistance.

Overview of SFP+ Direct Attach Copper Cable

SFP+ direct attach copper cable assembly is a high speed and cost-effective alternative to fiber optic cables in 10G Ethernet applications. 10g copper SFP is suitable for short distances, and ideal for highly cost-effective networking connectivity within a rack and between adjacent racks. It enables hardware OEMs and data center operators to achieve high port density and configurability at a low cost and reduced power requirement. SFP+ direct attach copper cable has been a good solution. This post will provide you with some basic information about SFP+ direct attach copper cable.

Introduction

SFP+ direct attach copper cable, also known as twinax cable, is an SFP+ cable assembly used in rack connections between servers and switches. It consists of a high speed copper cable and two SFP+ copper modules. SFP+ copper modules allow hardware manufactures to achieve high port density, configurability and utilization at a very low cost and reduced power budget. SFP+ copper cable assemblies meet the industry MSA for signal integrity performance. The cables are hot-removable and hot-insertable, which means that you can remove and replace them without powering off the switch or disrupting switch functions. A cable comprises a low-voltage cable assembly that connects directly into two SFP+ ports, one at each end of the cable. The cables use high-performance integrated duplex serial data links for bidirectional communication and are designed for data rates of up to 10 Gbps. The following picture shows a Cisco SFP-H10GB-ACU7M compatible 10G SFP+ direct attach copper twinax cable.

Types of SFP+ Direct Attach Copper Cables

Generally, SFP+ direct attach copper cable assemblies have two types, SFP+ active direct attach copper cable and SFP+ passive direct attach copper cable.

SFP+ Active Copper Cable: SFP+ active direct attach copper cable assemblies contain low power circuitry in the connector to boost the signal and are driven from the port without additional power requirements. The active version provides a low cost alternative to optical transceivers, and are generally used for end of row or middle of row data center architectures for interconnect distances of up to 15 meters.

SFP+ Passive Copper Cable: SFP+ passive direct attach copper cable assemblies offer high-speed connectivity between active equipment with SFP+ ports. The passive assemblies are compatible with hubs, switches, routers, servers, and network interface cards (NICs) from leading electronics manufacturers like Cisco, Juniper, etc.

Applications of SFP+ Direct Attach Copper Cables

• Serial data transmission
• Network Interface Cards (NICs)
• Data center cabling infrastructure
• Fibre Channel over Ethernet: 1, 2, 4 and 8G
• 10Gb Ethernet and Gigabit Ethernet (IEEE802.3ae)
• High density connections between networking equipment
• High capacity I/O in storage area networks, and storage servers
• InfiniBand standard SDR (2.5Gbps), DDR (5Gbps) and QDR (10Gbps)
• Switched fabric I/O such as ultra high bandwidth switches and routers

FAQs of SFP+ Direct Attach Copper Cables

1. Whether active or passive cable assemblies are required?
Active cable assemblies have signal amplification and equalization built into the assembly. They are typically used in host systems that do not employ EDC. Passive cables have no signal amplification in the assembly and rely on host system Electronic Dispersion Compensation (EDC) for signal amplification/equalization.

2. What are the performance requirements for the cable assembly?
Both SFP+ active and passive copper cable assemblies should meet the signal integrity requirements defined by the industry MSA SFF-8431.

3. What cable length and wire gauge are required?
Cable length and wire gauge are related to the performance characteristics of the cable assembly. Longer cable lengths require heavier wire gauge, while shorter cable lengths can utilize a smaller gauge cable. Smaller wire gauges results in reduced weight, improved airflow and a more flexible cable for ease of routing.

4. Are there any special customer requirements?
Examples of special customer requirements include: custom cable lengths, EEPROM programming, labeling and packaging, pull tab length and color, company logo, signal output de-emphasis, and signal output amplitude. You can order custom cables to your specific system architecture.

Conclusion

Fiberstore SFP+ twinax copper cables are available with custom version and brand compatible versions. All of them are 100% compatible with major brands like Cisco, HP, Juniper, Enterasys, Extreme, H3C and so on. Both passive twinax cables in lengths of 1, 3 and 5 meters, and active twinax cables in lengths of 7 and 10 meters are available. And the lengths can be customized up to the your requirements. You can get high quality compatible SFP+ cables and worldwide delivery from Fiberstore.

25GbE Cabling vs 40GbE Cabling

In recent years, 40 Gigabit Ethernet (GbE) has gained more popularity and the market of 40GbE is encouraging. But with the rapid growth of the new standard 100GbE, a new voice is announcing, namely 25GbE. As the increasing bandwidth requirements of private and public cloud data centers and communication service providers, 25GbE will to have a significant impact on server interconnect interfaces. Now you have two upgrade paths to 100G, 10G-25G-100G and 10G-40G-100G. Which one to choose? This post will make a comparison of 25GbE and 40GbE cabling, hoping it can help you make an appropriate decision.

25GbE Cabling Overview

25GbE is a standard developed by developed by IEEE 802.3 task forces P802.3by, used for Ethernet servers and switches connectivity in a datacenter environment. The single-lane design of 25 GbE gives it a low cost per bit, which enables cloud providers and large-scale data center operators to deploy fewer switches to meet the needs while still scaling their network infrastructure.

25GbE physical interface specification supports two main form factors, SFP28 (1x25 Gbps) and QSFP28 (4x25 Gbps). 25GBASE-SR SFP28 is an 850nm VCSEL 25GbE transceiver available in the market. It is designed to transmit and receive optical data over 50/125µm multi-mode optical fiber (MMF) and support up to 70m on OM3 MMF and 100m on OM4 MMF (LC duplex). In fact, using an SFP28 direct attach copper (DAC) cable for switches direct connection is a preferred option now. In addition, a more cost-effective solution is to use a QSFP28 to 4xSFP28 breakout cable to connect a 100GbE QSFP28 switch port with four SFP28 ports. DAC cable lengths are limited to three meters for 25GbE. Thus, active optic cable (AOC) solutions are also used for longer lengths of applications.

40GbE Cabling Overview

40GbE is a standard developed by the IEEE 802.3ba task force. The official development of 40GbE standards first began in January 2008, and were officially approved in June 2010. At the heart of the 40GbE network layer is a pair of transceivers connected by a fiber optic cable, OM4 or OM3 fiber cable. Fiber optic transceivers are plugged into either network servers or a variety of components, including interface cards and switches.

There are several standard form factors of 40GbE transceivers in the whole evolution. The CFP (C form-factor pluggable) transceiver uses 12 Tx and 12 Rx 10Gbps lanes to support one 100GbE port, or up to three 40GbE ports. With its large size, it can meet the needs of single-mode optics and can easily serve multi-mode optics or copper. But it is gradually falling behind since the increasing demand for high density. Another form factor is the CXP. It also provides twelve 10Gbps lanes in each direction, but is much smaller than the CFP and serves the needs of multi-mode optics and copper. At present, the most commonly used 40GbE form factor is the QSFP+ (quad small form-factor pluggable plus). It has the similar size with CXP but can provide four Tx and four Rx lanes to support 40GbE applications for single-mode, multi-mode fiber and copper.

Fiber optic cabling and copper cabling are both available for 40 GbE. The supportable channel length depends on the cable and the transceiver type. For data center 40GbE fiber optic cabling, OM3 and OM4 multi-mode cables are generally recommended because they can support a wider range of deployment configurations compared to copper solutions, and lower costs compared to single-mode solutions. MPO/MTP connectors are used at the multimode transceivers to support the multifiber parallel optics channels. For copper solutions, you can use QSFP+ direct attach copper cables, such as Cisco QSFP+ breakout cable. There are a lot of options, both active and passive, like Cisco QSFP-4SFP10G-CU5M compatible 40G QSFP+ to 4x10G SFP+ passive direct attach copper breakout cable (as shown below).

25GbE Cabling vs 40GbE Cabling

Compared to 40 GbE, 25GbE seems to be more suitable and cost-effective for cloud and web-scale data center applications. Using 25GbE with QSFP28 transceivers, users can deliver a single-lane connection, similar to the existing 10GbE technology but with 2.5X faster performance. In addition, 25GbE can provide superior switch port density by requiring just one lane (vs. 4 lanes with 40 GbE). Thus, it costs less and requires lower power consumption. Benefits of 25GbE compared to 40GbE are shown as below:

• Greater port density vs 40 GbE (one lane vs. four lanes)
• Maximum switch I/O performance and fabric capability
• Lower cost versus 40 GbE
• Reduced capital expenditures (CAPEX) and operational expenditures (OPEX)
• Fewer ToR switches and fewer cables
• Requires less power, cooling, and footprint
• Leverage of the existing IEEE 100GbE standard

Summary

25GbE seems to be a preferred option in the next step. It can provide up to 2.5 times faster performance than the existing 10GbE connections while maximizing the Ethernet controller bandwidth/pin and switch fabric capability. It can also provide greater port density with lower cost compared to 40GbE solutions. The trend will always be wider band and higher speed and port density. 25GbE or 40 GbE, let's wait and see how things play out.

FAQs About Compatible SFP Modules

SFP (small form-factor pluggable) was jointly developed by many of the world's leading network vendors. It has been widely used in optical network systems. Nowadays, many 3rd party SFP module vendors are providing high quality and reliable compatible SFP transceiver modules with low prices, such as compatible Cisco gigabit SFP, and using 3rd party SFP modules seems to be more and more popular now. Whether to choose compatible SFP modules or not? Here are some common questions that you might ask when using compatible SFP transceivers. Hope these answers can help you get a better understanding of compatible SFP modules.

1. What does 1000BASE-T or 1000BASE-X mean?

1000BASE-T is Gigabit Ethernet on copper cables, using four pairs of Category 5 unshielded twisted pair to achieve the gigabit data rate. 1000BASE-T can be used in data centers for server switching, for uplinks from desktop computer switches, or directly to the desktop for broadband applications. A big advantage of 1000BASE-T is that existing copper cabling can be used instead of having to rewire with optical fiber. 1000BASE-X is a group of standards for Ethernet physical layer standards, specified within the IEEE 802.3.z standard. It is used for Gigabit Ethernet connections that transmit data mainly over fiber optic cable. The standards that apply to the term 1000BASE-X include -LX, -SX, -BX10, -LX10, as well as non-standard -ZX and -EX standards. All of the standards that are grouped at 1000BASE-X utilize a 8b/10b encoding where 8 bits are reserved for data transmission while 2 bits are used for error correction.

2. How does transceiver compatibility work?

Each module holds its own information in EEPROM, and this memory is coded with unique identifiers such as part numbers and manufacturers details. The firmware of the host device then checks the memory for the correct information to confirm compatibility.

3. Why does my compatible SFP not work with the host device?

This is a common problem, a large amount of host devices do not have a firmware check for compatibility, this is known as an "open platform". Many SFP transceivers are sold as compatible when in fact they are open platform. They will work in many host devices but not in any that require coded transceivers. OEM SFP transceivers are coded specifically to suit each host device to avoid this problem, such as HP J4859C (as shown below) and HP JD118B SFP modules.

 

4. Will compatible SFP modules affect my host device warranty?

No, host device warranty will be unaffected. Please note that host device warranties do not cover SFP transceiver modules, OEM vendors offer lifetime warranties to protect them.

5. What is DOM support?

DOM, short for digital optical monitoring, is a feature used to monitor some parameters of the transceiver in real-time, helping to identify the location of the fiber link failure, simplify maintenance, and improve system reliability. DOM allows you to monitor the TX (transmit) and RX (receive) power of the module, temperature, and transceiver supply voltage. With DOM, network administrators can check and ensure that the module is functioning correctly in an easy and convenient way. This is why most of modern optical SFP transceivers support DOM functions.

6. Why choose compatible SFP modules?

In fact, most of the networking manufacturers do not produce their own SFP, XFP, SFP+, X2 transceivers, etc. They buy OEM transceivers, label them with their own brand and sell at a much higher price. You are basically paying a high price to have the respective manufacturers logo on the equipment. Besides, many compatible transceivers are made and assembled in exactly the same plants assembling officially-branded transceivers. There is almost no big difference between an official transceiver and a third-party plug, aside from the branding and about two hundred to a few thousand bucks.

7. How to identify the refurbished SFP module?

Here are three methods. First one is appearance recognition. Check the appearance of the SFP module. A new SFP module's appearance generally has good consistency while a refurbished SFP module is not glossy, and has some wear and scratches in the rim angle. Many refurbished SFP modules are replaced with new shells. If there is dust in the interface or the interface is not smooth, it is refurbished SFP module. Then you can check the ferrule. Pulling out the dust cap, you can see the ferrule in the bore. A second-hand old module is not glossy, and generally rough and with scratches, and it has a bad consistency. The ferrules of a new quality module is bright with color and lustre and has a good consistency. Last, you can put the module under the status of 50-60°C and see whether it can work properly. In general, a refurbished SFP module can not work well or even disconnect.

Summary

Various vendor-coded SFP modules are compatible to widespread networking equipment from well-known manufacturers. Fiberstore provides a variety of SFP transceiver modules that are compatible to devices of important vendors in the market. From production to shipmet, all these compatible SFP modules are tested and guaranteed 100% compatible and with high qulity.

Armored Fiber Patch Cable Overview

Fiber optic jumper cables, as one of the most common component in fiber optic networks, are a transmission medium used to transmit data via light. There are many types of fiber optic jumper cables. For example, by fiber optic cable types, there are single mode patch cable and multimode patch cord; by optical connector, there are ST ST fiber patch cable, LC SC fiber patch cable, and so on; and by fiber optic cable jacket, there are PVC and LSZH fiber patch cords. And you can even order custom fiber patch cables with custom lengths and colors. In this post, a type of fiber patch cord, armored fiber patch cable, will be introduced.

Structure

The outer sleeve of armored fiber patch cable is usually made of plastics, like polyethylene, to protect it against solvents and abrasions. The layer between sleeve and inner jacket is an armored layer made of materials that are quite difficult to cut, chew and burn. Besides, this kind of material is able to prevent armored fiber patch cable from being stretched during cable installation. Ripcords are usually provided directly under the armored and the inner sleeve to aid in stripping the layer for splicing the cable to connectors or terminators. And the inner jacket is a protective and flame retardant material to support the inner fiber cable bundle. The inner fiber cable bundle often includes structures to support the fibers inside, like fillers and strength members. Among them, there is usually a central strength member to support the whole fiber cable.

Features

Armored fiber patch cable, as a member of fiber optic jumper cables family, it retains all the features of standard fiber patch cables. Compared with those common patch cables, armored fiber patch cables are much stronger and tougher. For example, once stepped by an adult, standard patch cables may get damaged easily and fail to work normally. But armored fiber patch cables can withstand the pressure and perform well. Armored fiber patch cables are rodent-resistant, which means that you don't need to worry about rats biting the cables.

Basically, armored fiber patch cables offer benefits and features of traditional fiber patch cables, but they are with the production and durability of armor. Armored fiber patch cables allow high flexibility without causing damage, which proves to be helpful especially in limited space. Moreover, armored fiber patch cables offer an ideal option for harsh environments without adding extra protection. Apparently, they provide an efficient solution for many fiber cable problems such as twist, pressure and rodent damage.

Types

There are mainly two types of armored fiber patch cable, indoor armored fiber patch cable and outdoor armored fiber patch cable.

Indoor armored fiber patch cable is used for indoor applications. It consists of tight-buffered or loose-buffered optical fibers, strength members and an inner jacket. The inner jacket is commonly surrounded by a spirally wrapped interlocking metal tap armor. As the fiber optic communication technology develops rapidly with the trend of FTTX, there is a fast growing demand for installing indoor fiber optic cables between and inside buildings. Indoor fiber patch cable experiences less temperature and mechanical stress. Besides, it can retard fire effectively, which means it only emits a low level of smoke in the face of fire.

Outdoor armored fiber patch cable is designed to ensure operation safety of the fiber in complicated outdoor environments. Most outdoor armored fiber patch cables are loose buffer design, with the strength member in the middle of the whole cable, loose tubes surrounding the central strength member. Inside the loose tube there are waterproof gels filled, the whole cable materials and gels inside the cable between different components (not only inside the loose tube) help make the whole cable resist water. The combination of the outer jacket and the armor protects the fibers from gnawing animals and damages that occur during direct burial installations.

Applications

Armored fiber patch cable is generally adopted in direct buried outside plant applications where a rugged cable is needed for rodent resistance. It has metal armor between two jackets to prevent from rodent penetration. Armored fiber patch cables can withstand crush loads well. Another application of armored fiber patch cable is in data centers, in which cables are installed under the floor where it can be easily crushed. Single or double armored fiber patch cable is typically used underwater near shores and shoals. And armored fiber patch cords are also used in customer premises, central offices and in indoor harsh environments. They can provide flexible interconnection to active equipment, passive optical devices and cross-connects.

Conclusion

In summary, when transmitting data or conducting power in harsh environments, protecting your cables is crucial to safe and reliable operation. This is where armored fiber patch cables come into play. Armored fiber patch cables are used in applications where cables will be exposed to mechanical or environmental damage under normal operating conditions.