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What are the Recent Trends in Optical Fiber Cable Designs?

This might be an interesting topic of discussion to a few engineers engaged in fiber optic cable design. We don’t intend to provide any mathematical formula used in the fiber optic cable design in this post, but this may show you the trend in optical fiber cable design around the world.

Optical fiber cables with loose tubes are dominant in the European market. Loose tube technology is sophisticated compared to ribbon technology. Loose tubes need excess fiber length inside them in order to withstand temperature and mechanical effects. Excess fiber length or in short EFL is the key to loose tube technology. Controlling the excess fiber length in a loose tube is a skillful job. The theoretical calculation can guide the engineers to set the pay-off and take-up tensions, water trough temperatures, etc, but the practical manufacturing conditions are important factors to decide the excess fiber length. These may be different from factory to factory and needs optimization. This optimization requires analytical skills.

The inner diameter and therefore outer diameter of the loose tube was depending on the control of excess fiber length. Fiber cable manufacturing machine makers have come up with solutions to control excess fiber length in a loose tube. The outer diameter of a loose tube containing 12 fibers was around 3.0mm and the inner diameter was 2.0mm some years back. It was brought down to 2.5mm and 1.7mm respectively in an attempt to reduce the cable diameter and cable cost. For many years, 2.5mm was the standard loose tube size in many parts of the world. The last 10 years record shows that many cable manufacturers dared to experiment towards lower size loose tubes. Due to these efforts, 12 fibers loose tube size was brought down to around 2.2mm.

The development of microduct cables encouraged fiber optic cable manufacturers to further experiment with the lower sizes of loose tubes. In microduct cables, 12 fibers are put into a loose tube having an outer diameter of approximately 1.5mm and the inner diameter of approximately 1.1mm. Such a smaller size has been achievable with the support of machine suppliers. What is required is a small capstan in a loose tube line between the extruder and wheel capstan to control the excess fiber length.

Reduced size fiber optic cables become practically possible with the help of a small capstan or any other device to control the excess fiber length. The mechanical performances of the small size cables will not be equal to that of the big size cables. Smaller size cables require lesser force to install and therefore the required pulling strength will also be less. The changes towards lower sizes save material, manufacturing, and installation cost.

East Asian markets where ribbon technology is dominant followed basically the concept of reduced sizes of fiber optic cables. For example in Japan, NTT has driven research in fiber optic cable manufacturing facilities to use underground ducts to accommodate a maximum number of cables. The reduced slotted core diameter and development of thin ribbons made it possible to achieve smaller sizes for ribbon slotted core cables also. With NTT’s installation techniques a duct having 75mm outer diameter can accommodate 3 ribbon cables of 1000 fibers. This means 3000 optical fibers in a 75mm duct!

Recent trends show the development of smaller size cables around the world. If you have not still decided to develop smaller size cables, it is not too late. Smaller size cables will present severe competition in the tenders, where conventional cable makers will face threats. Responsible cable design engineers must put their efforts towards change in the design to reduce the cable cost.

Somethings you need to Know Before Selecting CWDM SFP Transceivers

As an extension of wavelength division multiplexing (WDM), coarse wavelength division multiplexing (CWDM) is a technology that multiplexes a number of optical carrier signals onto a single optical fiber through the use of different wavelengths (i.e., colors) of laser light.

A CWDM SFP (Small Form-factor Pluggable) transceiver is a hot-swappable input/output device that plugs into an SFP port or slot of a switch or router, linking the port with the fiber-optic network. It is a kind of optical-electric/electric-optical converter. With the transmitter on one end, the CWDM SFP transceiver takes in and converts the electrical signal into light, after the optical fiber transmission in the fiber cable plant, the receiver end again converts the light signal into electrical signal.

Being a kind of compact optical transceiver, CWDM SFP transceiver is widely used in optical communications for both telecommunication and data communication. It is designed for operations in Metro Access Rings and Point-to-Point networks using Synchronous Optical Network (SONET), SDH (Synchronous Digital Hierarchy), Gigabit Ethernet and Fiber Channel networking equipment.

Three Components of CWDM SFP Transceivers

The CWDM SFP transceiver consists of an un-cooled CWDM Distributed Feed Back (DFB) laser transmitter, a PIN photodiode integrated with a Trans-impedance Preamplifier (TIA) and a Microprogrammed Control Unit (MCU). The DFB laser used in the CWDM SFP transceiver transmitter is a 18 CWDM DFB wavelengths laser. It is well suited for high capacity reverse traffic. Obeying the standard diode equation for low frequency signals, The PIN photodiode has a 80km transmission distance. And the MCU is a high-speed, executive, input-output (I/O) processor and interrupt handler for the NRL Signal Processing Element (SPE).

Advantages of CWDM SFP Transceivers

Using existing fiber connections efficiently through the adoption of active wavelength multiplexing, CWDM SFP transceivers have improved the designs of telecommunications devices and other technologies. Here are some advantages of CWDM SFP transceivers:

1. Scalability and Flexibility

CWDM SFP transceivers can support multiple channels. It means that more channels can be activated as demand increases. CWDM SFP transceivers have a wide variety of network configurations that range from the meshed-ring configurations to the multi-channel point-to-point. In point-to-point configurations, the two endpoints will connect directly through a fiber link, allowing users to add or delete as many as eight channels at a time.

2. Low Risks in Investment

Most CDWM SFP transceivers have a low failure rate, which is less likely to be the reason why the user’s solution fails. It helps enterprises increase the bandwidth of the Gigabit Ethernet optical infrastructure without adding any additional fiber strands and can also be used in conjunction with other SFP devices on the same platform. Thus the user will be able to re-invest the capital saved by avoiding prematurely failed devices.

Selecting a Right CWDM SFP Transceiver

There are many kinds of CDWM SFP transceivers in the market. Their wavelengths are available from 1270 nm to 1610 nm, with each step 20 nm. Different CDWM SFP transceivers have different color codes, distances, data rates and laser operating wavelengths. For example, the CWDM-SFP-1470 transceiver, which is colored gray, is one of Cisco CWDM SFP. It is a CWDM SFP transceiver that rates for distances up to 80 km and a maximum bandwidth of less tan 1.5 Gbps, operating at 1470nm wavelength.

CWDM-SFP-1490 transceiver, however, is designed for single mode fiber and operates at a nominal wavelength of CWDM wavelength. Colored purple, it rates for distances up to 80 km and a maximum bandwidth of 1.5 Gbps, operating at 1490 nm wavelength. Cisco CWDM-SFP-1470Cisco CWDM-SFP-1490 Customers may choose a CWDM SFP transceiver in accordance with their actual needs. Applied to the access layer of Metropolitan Area Network (MAN), The CWDM SFP is a low-cost WDM transmission technology.

fiber-mart.com provides the aforesaid CWDM-SFP-1470, CWDM-SFP-1490 and other types of CDWM SFP Transceivers, which are convenient and cost-effective solution for the adoption of Gigabit Ethernet and Fiber Channel (FC) in campus, data center, and metropolitan-area access networks.

Compatible Juniper QSFP+ LX4 Transceiver Introduction

In today’s data center communications, individual streams routinely reach 10 Gbps speeds, and it is necessary to have 40GbE links to provide better performance. Such high-performance, high-density 40 Gbps network devices such as Juniper Networks switches, when equipped with LX4 optics, seamlessly enable this transition. This article introduces Juniper QSFP+ LX4 transceiver in details.

The Rise of 40 Gbps QSFP+ LX4 Technology

Short-reach (SR) and extended short reach (eSR4) transceivers for 40 Gbps connectivity in a quad small form-factor pluggable transceiver (QSFP) mode use independent transmit and receive sections, each with four parallel fiber strands. For a duplex 40 Gbps connection, eight fiber strands are required, while QSFP SR4 uses Multipath Optical (MPO) 12-fiber connectors (MPO-12F). This IEEE standard technology must reach up to 400m using OM4 and provide future support for 100 Gbps speeds using the same cabling infrastructure. However, this technology requires more fiber strands than can be found in today’s 10 Gbps infrastructures, which means that data centers require a cabling upgrade. Juniper offers an innovative alternative: a 40 Gbps QSFP plus (QSFP+) LX4 technology that allows for zero-cost fiber migration by reusing the current 10 Gbps multi-mode fiber optic (MMF) cabling plant for 40 Gbps connectivity.

Introduction to Juniper 40 Gbps QSFP+ LX4

Juniper offers a new 40 Gbps Ethernet optical technology called LX4 and provides a QSFP+ 40GbE optical module that uses the same infrastructure as 10GbE. The LX4 technology represents a new way to deploy 40GbE that meets all of the performance criteria of today’s data centers by providing 40GbE on two MMF strands and duplex LC connectors. The Juniper QSFP+ LX4 transceiver addresses the challenges of fiber infrastructure by providing the ability to transmit full-duplex 40 Gbps traffic over one duplex MMF cable with LC connectors. In other words, the Juniper QSFP+ LX4 transceiver, a short-reach optical transceiver that delivers 40 Gbps over duplex OM3 or OM4 MMF, allows 40 Gbps connectivity to connect directly to the 10 Gbps fiber and fiber trunk.

The Juniper QSFP+ LX4 transceiver has four 10 Gbps channels, each of which can transmit and receive simultaneously on four wavelengths over a MMF strand. The result is an aggregated duplex 40 Gbps link over a duplex of two MMF strands. Using duplex LC connectors, QSFP+ LX4 connections can reach 100 meters on OM3 MMF or 150 meters on OM4 MMF.

About fiber-mart.com’s 40G QSFP+ LX4 Transceivers

As a professional manufacturer and supplier for optical fiber products as well as third-party, fiber-mart.com’s 40G QSFP+ LX4 transceivers support highly reliable operations in data center networks, and are optimized for various switching platforms by offering the perfect compatibility with brands, such as Juniper. The fiber-mart.com compatible Juniper 40G QSFP+ LX4 transceiver can save you a lot of budget and provides the same functions just as Juniper 40G QSFP+ LX4 transceiver. And there is no need to worry about the quality or performance of 40G QSFP+ LX4 transceiver offered by fiber-mart.com.

Features of fiber-mart.com’s compatible Juniper 40G QSFP+ LX4 Transceivers:

QSFP+ MSA compliant

EEE 802.3ba Electrical Interface

LC duplex connector

Up to 150m over duplex OM3 or OM4 fiber, 500m over duplex single-mode fiber

Compliance with Restriction on Hazardous Substances (RoHS) directive

Conclusion

All fiber-mart.com’s 40G QSFP+ LX4 transceivers, including the compatible ones mentioned above, provide high density and ensure high quality. Besides, fiber-mart.com’s compatible Juniper 10G SFP/XFP transceivers and 1000G SFP transceivers, like EX-SFP-10GE-LR, XFP-10G-E-OC192-IR2, JX-SFP-1000BASE-T are also available. For more information about fiber-mart.com 100% compatible transceivers with Juniper, please visit fiber-mart.com.

The Way to Choose Suitable Patch Cable for Optical Transceiver?

People are always amazed by the fast development of optical communication. Fiber optic transceiver, a small-size but important component, can best represent the advancing of the optical communication industry. The form factor of optical transceiver has changed from GBIC for Gigabit Ethernet to SFP+ for 10GbE, QSFP+ for 40GbE and CFP or QSFP28 for 100GbE. It is not difficult to tell the differences among these transceivers. However, users may feel confused about the patch cable which is used to connect optical transceiver to the telecommunication network. This post will introduce how to choose the suitable patch cable for optical transceiver from the aspects of transmission media, transmission distance & rate, and interface.

Optical Transceiver and Patch Cable Overview

Optical transceiver or optical transmitter and receiver (shown in the following picture) is a device that uses fiber optics technology to send and receive data. The transceiver has electronic components to condition and encode/decode data into light pulses and then send them to the other end as electrical signals. To send data as light, it makes use of a light source, which is controlled by the electronic parts, and to receive light pulses, it makes use of a photodiode semiconductor. There are different types of transceivers for different Ethernet networks, such as 1G GBIC, 10G SFP+, 40G QSFP+, etc.

A patch cable or patch cord is an electrical or optical cable used to connect one electronic or optical device to another for signal routing. It is composed of electrical or optical cable terminated with connectors at each end. Optical patch cable is the most popular cable widely applied in data center and telecommunication networks. They can be differ from different connector types (see in the image below), like LC, SC, ST and FC, etc, different core diameters, like single-mode optical patch cable, multimode optical patch cable, and different fiber cable structure, like simplex optical patch cable and duplex optical patch cable.

Factors to Consider When Choosing patch cable for Optical Transceiver

Transmission Media

As we all know, there are two kinds of transmission medias in the network—fiber optic and copper. Therefore, based on these two media types, transceivers can be divided into fiber optic based transceiver and copper based transceiver. Copper based transceiver, such as 1000Base-T SFP and 10GBase-SFP+, which usually has a RJ45 interface, can achieve connection to the network with the use of cat5/6/7 patch cables.

Compared to copper based transceiver, patch cable choices for fiber optic based cable are more complicated. Generally, fiber optic patch cable comes in two types: single-mode fiber patch cable and multimode fiber patch cable, and each type can be used in different applications. Single-mode fiber patch cable can be further classified into OS1 and OS2, while multimode fiber patch cable can be further divided into OM1. OM2, OM3 and OM4. Single-mode fiber optic cable has a small diameter core that allows only one mode of light to propagate, so it is suitable for long distances data transmission. On the contrary, multimode fiber optic cable has a large diameter core that allows multiple modes of light to propagate, thus it is available for short distance data transmission. Typically, if the transmission distance is shorter than 500 meters, multimode fiber optic cable is suggested, otherwise, the single-mode fiber patch cable is a better choice.

Transmission Distance and Rate

It is known that the transmission rate will decrease as the transmission distance increases. Single-mode fiber patch cable can provide higher performance for different rates in both short and long distances, but it will cost more. When it comes to short transmission distance, it’s better to choose multimode fiber patch cable. As we have mentioned above, multimode fiber patch cable can be classified into OM1, OM2, OM3 and OM4.

OM1 patch cable supports 10 Gigabit Ethernet applications at 33 m, but is usually used for 100 Megabit Ethernet applications, while OM2 patch cable is standardized to support 10 Gigabit Ethernet applications at 82 m, but is usually applied for 1 Gigabit Ethernet applications. OM3 patch cable is commonly used to run 10 Gigabit Ethernet applications at 300 m, though it has been improved to work with 40G and 100G Ethernet applications if using a MPO connector. OM4 patch cable is optimized to support 10 Gigabit Ethernet at length up to 550 m, and 100 Gigabit Ethernet at 150 m with MPO connectors. The different performances of multimode fiber patch cable types are shown in the table below.

Transceiver Interface

Transceiver interface is also an important factor when selecting patch cable for transceiver. Most optical transceivers have two ports, one port for transmitting and one port for receiving, so duplex SC and LC interfaces are usually employed. However, for BiDi transceiver which has only one port for both transmitting and receiving, simplex fiber patch cords will be used. For 40G QSFP+ transceivers, which often use MPO/MTP interfaces, multimode fiber patch cords attached with MPO/MTP connectors will be deployed.

Conclusion

Optical transceiver and patch cable are both vital components in telecommunication networks. Without any of these two devices, the network connection can be achieved. Only matched optical transceivers and patch cables can provide better performance. Through the information that we have mentioned above, hope you can choose the suitable patch cable for your optical transceiver.

Three Cisco SFP Module Types Brief Introduction

Although the 10 Gigabit Ethernet system has become the dominant deployment in telecommunication market, there are still many 1GbE infrastructures existing in today’s networks. SFP optical transceiver, as a critical component to support 1G data transmission, is also increasingly required in most Gigabit Ethernet networks. Many vendors, like Cisco, one of the most well-known and reliable company in telecommunication industry, have provided various types of SFP transceiver modules to the market. This post aims to introduce three common Cisco SFP module types for you references.

SFP Optical Transceiver Overview

SFP (small form factor pluggable) transceivers are hot-plugable and compact optical transceivers which provide instant fiber or copper connectivity for SONET, Gigabit Ethernet, Fibre Channel, and other communications standards. They are a cost-effective way to connect a single network device to a wide variety of fiber cable distances and types. With the existence of SFP module, network upgrades could be easier, since SFP is interchangeable fiber connectors that can adapt to any existing network. For example, by simply replacing the pluggable optical transceiver, a media converter that was originally used in a multimode network can be re-configured to operate over a CWDM network. SFP optics come in four versions: 1000Base-T, 1000Base-SX, 1000Base-LX, and 1000Base-ZX. The 1000Base-SX will work on multimode fiber for the link length of 550 m, while the 1000Base-LX and 1000Base-ZX work only on single-mode fiber for the maximum distance of 10 km and 80 km respectively, and the 1000Base-T is the RJ-45 version. The following image shows the structure of SFP module.

Three Common Cisco SFP Module Types

GLC-SX-MM SFP: GLC-SX-MM 1000Base-SX SFP is a duplex SFP transceiver used over multimode fiber at the wavelength of 850 nm for optical communications. It is compatible with IEEE 802.3z and could support the data rate of 1Gbps for the reach of 550 meters over 50/125 multimode fiber, and 220 meters over 62.5/125 multimode fiber. But since March 8th, 2013, there is no longer GLC-SX-MM SFP modules on sale in Cisco. It is replaced by the new model SFP transceiver module—GLC-SX-MMD SFP. However, for usage and cost considerations, many users still use the old model SFP, because GLC-SX-MMD is much more expensive, and except the additional DOM function, they work as the same when used in Cisco switch. These old Cisco compatible GLC-SX-MM SFPs can be still purchased in Fiber-mart at very lower prices as shown in the following image.

GLC-LX-SM SFP: GLC-LH-SM 1000Base-LX-LH Ethernet transceiver is a LC duplex SFP transceiver used for optical networks. It operates at 1310 wavelength, rated for distances up to 10 km and a maximum bandwidth of 1Gbps. This type of SFP module is compliant with MSA (multisource agreement) and the IEEE 802.3z 1000Base-LX standard, which can both operate over single-mode fiber for the link spans of up to 10 km and up to 550 m on any multimode fibers. The following picture is Cisco GLC-LH-SM-15 Compatible 1000BASE-LXLH SFP in Fiber-mart.

GLC-T SFP: GLC-T (as shown below) is a type of copper SFP module used over standard Cat5 unshielded twisted pair copper cabling of link length up to 100 m (328ft). It provides 1Gbps data transfer and offers full-duplex Gigabit Ethernet connectivity to high-end workstations and between wiring closets over existing copper network infrastructure. Cisco GLC-T SFP transceiver module can offer a flexible and simple method to be installed into SFP MSA compliant ports at any time with no interruption of the host equipment operation. It enables for seamless integration of fiber with copper LAN connections wherever SFP interface slots can be found.

Summary

We have mentioned three commonly used Cisco SFP modules in the previous text, and each module is applied in different applications. GLC-SX-MM SFP is used for multimode fiber based equipment, while GLC-LX-SM SFP is more suitable for single-mode fiber based infrastructure and GLC-T SFP is often deployed with copper cable, like Cat5 Ethernet cable. Besides these aspects, you should also take your budget into consideration. As we all know, Cisco brand SFP transceiver is expensive, but with the increasing popularity of third-party modules, we have a good alternative. Fiber-mart provides a wide range of Cisco compatible SFP modules at affordable prices. If you have related needs, please visit fiber-mart.COM for more information.

Why Should You Use MTP Cassette in Your Network?

The increasing demand for bandwidth and fast speed have driven the advent of 40G and 100G application on the market. As the increasing created data needs amount of cables and devices to achieve the transmission, which could be a headache for IT manager to create a high-density data center. To handle these requirements, MTP technology offers an ideal condition for setting up high-performance data networks in data centers. This post tends to introduce an indispensable device used in MTP system—MTP cassette and to indicate why should you use it in your network.

What Is MTP Cassette?

MTP cassette is a modular module which is used to break out the 12-fiber MTP connectors terminated on trunk cables into simplex- or duplex-style connectors, then the simplex- and duplex-style jumpers can be used to patch into transceiver terminal equipment ports, patch panels or client ports. The MTP cassette is made of simplex or duplex port adapters across the front and one or two 12-fiber MTP connector adapters across the back. A factory-installed and tested optical fiber assembly inside the module connects the front adapters to the back MTP connector adapter. (Note: alignment pins are pre-installed in the MTP connector located inside the cassette.) Generally, according to the amount of 12-fiber MTP connector adapter used on the back of cassette, there is 12-fiber MTP cassette and 24-fiber cassette as shown below. (Note: a special type of 24-fiber MTP cassette only uses one 24-fiber connector adapter on the cassette back.)

What Can MTP Cassette Bring for Us?

Simplify the Installation: In order to satisfy the ever-increasing need for human beings, the technology will face refresh every 12 to 18 months. Plug-n-Play MTP cassette provides great adaptability for the changing data center environment. If the connector requirements change in the future, we just need to swap the cassette and leave the existing backbone infrastructure intact. Besides, 12-fiber MTP to LC and 24-fiber MTP to LC cassettes provide a quick and efficient way to deploy up to 12 LC or 24 LC fiber ports in a single module respectively. Since MTP to LC cassette with MTP or MPO trunk cable offers great flexibility for different applications, it is possible to add the exact fiber requirement with no excess fiber installed. With such quick and easy installation, the additional fiber links can be added at a time that suits the demands of your business. The image below shows equipment inter-connect (LC to LC) with MTP cassette and MTP trunk cable.

Minimize Space-Occupying: As more and more devices are used in data center, IT managers are turning to equipment which can provide high density. That’s why switch equipment manufacturers are focusing on increasing the fiber port density in their switches, which has driven the need to be able to increase the number of fibers per 1U in fiber management products. Normally, 1U MTP patch panel can accommodate up to three MTP cassettes, resulting in a maximum of 72 terminations in it, while 4U MTP patch panel can accommodate up to 12 MTP cassettes, give a high connectivity of 288 fiber termination per panel as shown below. This high-density design not only minimizes the space-occupying to the extreme, but also offers a flexible solution to the end user with the a full array of adapter types, enabling users to incorporate a multi functional panel which allows easy easy access during installation or re-work with no disturbance of the existing cable or fibers.

Easy Cable Management: As networking equipment becomes denser and port counts in the data center increase to hundreds and thousands of ports, managing cables connected to these devices becomes a difficult challenge. Traditionally, connecting cables directly to individual ports on low port-count equipment was considered manageable, but applying the same principles to high port-count equipment will make the task more tedious. With MTP cassette, any port from any device can be connected to any other port, which can make the cable management easier as we can see from the following image.

Conclusion

For high density application, MTP cassette is an dispensable component that you should apply. With the advantages that MTP cassette takes we have talked above, it is time to use MTP cassette in your network. fiber-mart.COM provides a series of MTP cassettes and MTP trunk cables for your practical application. If you have any need, just come to fiber-mart.COM.