How to Classify Fiber Optic Transceivers

With the technological advancements in fiber optic communication, service providers tend to choose fiber optic to achieve high-level data transmission. Fiber optics generally offer users higher bandwidth, more reliable data transfer and better overall performance, thus enabling a smooth and excellent communicating experience. Fiber optic transceiver, which is considered to be the core of optoelectronic device in the WAN, MAN or LAN infrastructure, plays an indispensable part in fiber optic networks for data communication and Ethernet applications. This article will explain how fiber optic transceivers are classified according to different criteria such as fiber mode, transfer rate and connector type.

Fiber Optic Transceiver Overview

First of all, let’s take a quick glimpse of what fiber optic transceiver is and how fiber optic transceiver works.

Fiber optic transceivers combine a fiber optic transmitter and a fiber optic receiver in a single module. They are arranged in parallel so that they can operate independently of each other. Both the receiver and the transmitter have their own circuitry and can handle transmissions in both directions. In fiber optic data links, the transmitter converts an electrical signal into an optical signal, which is coupled with a connector and transmitted through a fiber optic cable. The light from the end of the cable is coupled to a receiver, where a detector converts the light signal back into electrical signal. Either a light emitting diode (LED) or a laser diode is used as the light source.

Common Classification Methods

The classification of fiber optic transceiver falls into various categories based on their performance characteristics and end-use. Classified by characteristics, they often include: fiber mode, transfer rate and connector type.

Fiber Mode
Fiber mode is the most fundamental classification of fiber optic transceivers, here the “mode” refers to the type of fiber intended to be used with a transceiver. The two primary types of fiber mode types are single-mode fiber and multimode fiber.

Multimode fibers allow multiple modes of light to couple into the fiber. Since multimode applications are always short reach, very inexpensive transmitters and receivers are typically used in multimode transceivers. As shown in the table below, there are several popular types of multimode fibers in use today. OM1 and OM2 fibers are appropriate for low speed transmission, such as 100 Mbps to 1 Gbps, which often utilize LED transmitters. OM3 and OM4 are referred to as laser-optimized multimode fibers, as lasers are used as optical sources at 10Gbps and faster. For example, Cisco Meraki MA-SFP-10GB-SR transceiver can achieve 300 meters over OM3 multimode fibers.

Single-mode fibers, however, only allow a single mode of light to couple into the core. The most common type of single-mode fiber is termed “OS1” by the ITU and is also known as “standard single-mode fiber”. So most optical transceivers are simply specified for operation over OS1.

Transfer Rate
Fiber optic transceiver modules also can be categorized by their data transfer rates. There are five popular rate categories used in fiber optic transceiver classification: 100GBase, 40GBase, 10GBase, 1000Base and 100Base. These rates refer to the speed at which a fiber optic transceiver is able to transmit data over Ethernet.

• 100GBase—100 Gigabits per second (100GE, 100GbE, 100Gbps)
• 40GBase—40 Gigabits per second (40GE, 40GbE, 40Gbps)
• 10GBase—10 Gigabits per second (10GE, 10GbE, 10Gbps)
• 1000Base—1 Gigabit per second (1GE, 1GbE, 1Gbps, 1000Mbps)
• 100Base—100 Megabits per second (Fast Ethernet, FE, 100Mbps)

Connector type
Optical fiber connectors couple and align transceivers so that light can pass through the core. Based on their connector types,transceiver modules can be classified into different groups. There are four main types of fiber optic connectors used in conjunction with optical transceivers: SC, LC, MPO, and ST.

Connector types generally follow a color code system. If a boot is used over the connector, then a blue boot symbolizes compatibility with single-mode fiber and a beige boot symbolizes compatibility with multimode fiber.

Conclusion

Choosing which type of fiber optic transceivers mainly depends on your applications and requirements in reality. FS.COM offers you a full range of optical transceivers, such as SFP+ (SFP Plus) transceiver, X2 transceiver, XENPAK transceiver, XFP transceiver, SFP (Mini GBIC) transceiver, GBIC transceiver, CWDM/DWDM transceiver, 40G QSFP+ & CFP, 3G-SDI video SFP, WDM Bi-Directional transceiver and PON transceiver. All these fiber optic transceivers are 100% compatible with major brands like Cisco, HP, Juniper, Nortel, Force10, D-link, 3Com. They are backed by a lifetime warranty, and you can buy with confidence.

Selecting 10G SFP+ Optics Modules and Patch Cables

Nowadays, 10G connection in telecommunication network is gradually moving from the backbone to layer 2 and layer 3. Both technology and market of 10G optics modules are mature: the 10G optics modules have advanced from XENPAK which is the first generation of 10G transceiver to SFP+ which is now the most popular 10G optics. In addition, the price of 10G modules is getting lower. 10G modules are becoming affordable. Some genius guys even buy 10 SFP+ modules or SFP+ cable online to DIY private point to point 10G network. This article will offer basic information about 10G SFP+ optics modules and their connection instructions.

Basic of 10G SFP+ Optics

10G SFP+ transceiver has the same form factor of Gigabit SFP transceiver. Thus, many SFP+ modules can support 1/10G data rate to increase its flexibility during practical using. A SFP+ transceiver usually has two LC ports (as shown in the following picture). While 10G BiDi SFP+ transceiver, which transmitting and receiving signals from the same fiber optic cable, only has one LC port.

Apart from fiber optic transceivers, there are also various factory terminated copper-based or fiber optic based cables which are terminated with a SFP+ module on each end of the cable. There are mainly three types of these 10G cables: 10G SFP+ passive direct attached copper cable (like HP J9283B), 10G active direct attached copper cable and 10G SFP+ active optical cable. These 10G cables eliminate the used of additional patch cable and can be directly plugged into the SFP+ ports on switches. It is acceptable that these cables are an cost-effective and reliable solutions for 10G connections in short distance.

Optical Standards of 10G SFP+ Transceiver

According to IEEE standards, there are a variety 10GBASE SFP+ transceivers. For short distance transmission, 10GBASE-SR SFP+ and 10GBASE-LRM SFP+ can support transmission distance up to 300 meters and 220 meters over multimode fiber optic cables separately. 10GBASE-SR SFP+ modules is the most commonly used transceiver for short distance. It is suggested to work over wavelength of 850 nm.

There are a lot of 10G SFP+ transceivers that support long distance, like 10GBASE-LR SFP+, 10GBASE-ER SFP+, 10GBASE-ZR SFP+, CWDM SFP+, DWDM SFP+, BiDi SFP+, etc. These transceivers can support transmission distances ranging from 10 km to 120 km over single-mode fiber optic cables.

There is another special type of 10G SFP+ transceivers which has been mentioned in this post, which is known as dual-rate SFP+. For example, dual-rate 1000BASE-LX and 10GBASE-LR SFP+ transceiver can be adjusted to support both 1G and 10G data rate up to 10 km over wavelength of 1310 nm.

Fiber Patch Cable Selection Guide for 10G Transceivers

As 10G SFP+ DAC and AOC eliminate the using of additional patch cords. This part will introduce the selection guide for 10G SFP+ transceivers. During the selection of fiber optic patch cables for 10G transceivers, the transmission distance is the first element to be considered. Single-mode patch cable is used for long distance transmission and multimode is designed for short distance transmission. Then the ports on the transceiver for receiving and transmitting should be considered. As mentioned, most 10G SFP+ transceiver use duplex LC port, while BiDi SFP+ use simplex port. Thus, simplex LC patch cords or duplex LC patch cords are used according to the port type on the transceiver.

Conclusion

Although newer standards for higher speed, like 40Gbps and 100Gbps have already been launched, it can still be predicted that, 10G connections especially the SFP+ based optics and cables are bound to continue to dominate the market for the next 10 years or more.

AOC—the Ideal High-Speed Interconnect Solution

What is the Ideal High-Speed Interconnect Solution?

The ideal high-speed interconnect solution should have such features as optimized for short distances, low cost, low power consumption, small cable bend radius, low cable weight, high density, and low link latency. The only one solution which can meet all the requirements is the direct attach active optical cables.

Direct attach active optical cables, or active optical cables for short, are direct-attach fiber assemblies with optical transceiver (SFP+, XFP, QSFP+, CXP etc.) connectors. They are suitable for short distances and offer a cost-effective way to connect within racks and across adjacent racks. Nowadays the Active Optical Cable (AOC) is accelerating data connectivity for storage, networking, and HPC applications. It leverages fiber optic technology for the transmission of data while reducing the weight, density and power consumption of traditional copper solutions. For example, the 40G active optical cable (AOC) is a type of active optical cable for 40GbE applications that is terminated with 40GBASE QSFP+ on one end, while on the other end, besides QSFP+ connector, it can be terminated with SFP+ connectors, LC connectors, etc. 40G active optical cables have great advantages over 40G copper QSFP+ cable when transmission distance reaches up to 7 meters. Moreover, 40G AOC has lower weight and tighter bend radius, which enables simpler cable management.

Advantages of Active Optical Cables

The AOC assemblies provide the lowest total cost solution for data centers by having the key advantages as following:

• Low weight for high port count architectures;
• Small bend radius for easy installations;
• Low power consumption enabling a greener environment.

Compared to Active & Passive Copper Cable Assemblies

1. Longer reach (> 7 meters)

2. Lower weight and tighter bend radius enable simpler cable management

3. Thinner cable allows better airflow for cooling

4. Lower power consumption

5. No need for power-hungry conditioning ICs on the host board

6. Can be used in architectures with challenging cable routing

Compared to Optical Transceivers

1. Datacenter/Consumer friendly: No cleanliness issues in optical connector

2. Cost-optimized: Not constrained by optical interface specifications driven by longer reach applications

(Note: However, the active optical cables cannot be routed through fiber patch panels.)

Ideal High-Speed Interconnect Solution

Today’s enterprise data centers and networking environments are undergoing an infrastructure transformation, requiring higher speeds, greater scalability, and higher levels of performance and reliability to better meet the demands of business. As speed and performance demands increase, the AOC assemblies have become an integral part of the overall system design. However, AOC design margins and parameters vary widely, and can be the difference between an optimized, highly reliable fabric and the incompatibility issues that drive up support costs. There are various types of AOC assemblies for 10G, 40G, and 100G applications on the market. Judging from the cost performance, FS.COM can provide the most ideal high-speed interconnect solution of AOC assemblies including 10G SFP+ AOC, 40G QSFP+ AOC, 40G QSFP+ to 4×SFP+ AOC, 40G QSFP+ to 8×LC AOC, and 120G CXP AOC.

Learn to Identify Various Fiber Patch Cables

Fiber patch cable, also called fiber patch cord is the most fundamental component in today’s fiber optic network. It is the core of fiber optic connectivity in communication systems. However, many people are only familiar with the most common standard fiber patch cable. In fact, various kinds of fiber patch cables with unique and special functionality are already available in the market. This article will introduce several types of these fiber patch cables and tells you how to identify them.

How to Select Standard Fiber Patch Cable?

When selecting the standard fiber patch cables, the followings are the most frequently asked questions.

• What’s the fiber type of the patch cable? The available selection are Multimode (OM1, OM2, OM3, OM4) and single-mode (OS1 and OS2).
• What’s the connector type and connector polishing type on the two ends of fiber patch cable? Currently the most commonly used fiber patch cables are usually terminated with LC, SC and MPO connectors. For example, an SC LC fiber patch cable is terminated with one SC connector on one end and one LC connector on the other end, while the LC LC cable is with two LC connectors on each end.
• What’s the fiber count of the patch cable? Simplex (one fiber) and duplex (2 fibers) fiber patch cable are very common. For fiber patch cables terminated with MTP/MPO connector or breakout fiber patch cables. Their fiber count would be larger, sometime up to 24 fibers or more.
• What’s the material of the fiber patch cable jacket? PVC, LSZH, Armored, and OFNP are the choice of most situations.

Not All Fiber Patch Cable Are Created Equal

With the wide deployment of fiber patch cables in fiber optic communication, the requests for fiber patch cables are gradually being refined. Fiber patch cables are expected to provide more functions to satisfy various application environments. Actually, many specially made fiber patch cables have been created to meet these requirements. Here are some unique but useful fiber patch cables for your references.

Bend Insensitive Fiber Patch Cable for Lower Signal Loss

Bend loss issues are always a headache problem for most fiber optic network designers and installers. Why? Cause signal loss caused by bend loss issues are really hard to handle. In addition the bend loss issues are difficult to locate. That’s why bend insensitive fiber patch cables are created. Literally, it tells us that this type of fiber patch cable is not as sensitive as other fiber patch cables. The secrets is lays on the fibers which is made of bend insensitive glass. More and more data centers and FTTH systems are tend to use these bend insensitive fiber patch cables, because they do not provide lower signal loss, but also provide a much more durable and easy to maintain networking environment. Fiber optic installer is able to save installation cost with faster installation due to easier fiber optic cable handling.

Keyed LC Fiber Patch Cable for Data Security

Keyed LC fiber patch cable, is also called secured LC fiber patch cable. Because fiber optic connectors on the two ends of fiber patch cables are specially designed as LC connectors, which can ensure the data security at the mechanic level. Keyed LC fiber patch cable is identified by the connector color. Keyed LC fiber patch cable is just a part of the Keyed LC connectivity product family. It should be used with the same colored fiber adapters or fiber adapter panels. Each color of a set of keyed LC connectivity products represents a unique keying pattern that only allows matched color mating. This is how keyed LC fiber patch cable can provide data security for fiber optic network.

Uniboot LC Fiber Patch Cable for Easier Cable Management

Uniboot LC fiber patch cable is a fiber patch cable with two fibers wrapped in the same strand of cable. A duplex LC fiber optic connector which can provide easy polarity reversal is terminated on each end of the uniboot LC fiber patch cable. The following picture show the polarity reversal of a typical uniboot LC fiber patch cable. With less cabling space are require, better cooling is available. With easier polarity reversal, no additional tools are required. And easier cable management can be enjoyed.

HD TAB Fiber Patch Cable for Space Saving

HD (high density) TAB fiber patch cable is a fiber patch cable with its connectors attached with a push pull tab, which can provide easier finger access and cable locating. Today’s fiber optic network is increasing depended on high density which results in difficult finger access and difficult cable management. With a push-pull tab attached on the connector, problem are solved easily. The connecting and disconnection of fiber patch cables will be easier without affecting other surrounding links. Currently most HD TAB fiber patch cables available the market are terminated with LC and MTP/MPO connectors.

HD Uniboot LC Fiber Patch Cable—Space Saving to the Extreme

HD uniboot LC fiber patch cable combine the advantages of uniboot LC fiber patch cable and HD TAB fiber patch cable. Combining two optical fibers in a single cable strand and attaching a push-pull tab on the connectors, HD uniboot LC fiber patch cable can minimize the required cabling spaces to extreme. It is an ideal solution for high density cabling environment.