Classification Guide to Fiber Optical Module

Owing to the rapid progresses made in fiber optical technology, more and more networking infrastructure installations and upgrades choose fiber optic links for high-data-rate transmission. There is no question that compared with copper solutions, fiber optics provides greater bandwidth, more reliable data transmission, and immunity to electromagnetic interference and radio-frequency interference (EMI/RFI), crosstalk, impedance problems, and more. For constituting such fiber optic links, fiber optic module, one of the fast-growing transmission components, are instrumental, and work well in these applications where high-bandwidth and long-distance transmission are needed.

Along with the fiber optical technology advances, fiber optic module has been constantly designed and reinnovated, so as to better facilitate electrical-optical-electrical signal conversion. They are classified into several categories according to different standards regarding package, transmission mode, data rate and power supply. This text will talk about every classification standard in details.

Based-on Different Package Standard

MSAs (Multi-Source Agreements) are agreements between multiple manufacturers, system integrators, and suppliers, specifying parameters for system components and their guideline values, such as the electrical and optical interfaces, mechanical dimensions and electro-magnetic values. The equipment vendors follow these MSA defined values for designing their systems to ensure interoperability between interface modules. The form-factor or the MSA-type is needed so that the transceiver can mechanically and electrically fit into a given switch, router, etc. Transceiver MSAs define mechanical form factors including electric interface as well as power consumption and cable connector types. There are various MSA types: SFP (eg. E1MG-TX), SFP+, QSFP and so on.

fiber optical modules

By Transmission Mode Standard

When talking about this standard, single mode optical modules and multi-mode optical modules come to the central point.

  • Single Mode Fiber Optic Module

Single-mode optical modules, or single-mode transceivers, just as their name show, are designed to work over single mode fibers (SMFs). Compared with multimode fiber (MMF), SMF fiber core is smaller and the wavelength of the laser is narrower, meaning that while transmitting optical signals, SMF is able to deliver higher bandwidth at the much longer distances, like 2km, 10km, 40km, 60km, 80km and 120km transmission. Commonly-seen single-mode transceiver types include 10GBASE-LR, 1000BASE-LR, 1000BASE-BX, etc..

  • Multimode Fiber Optic Module

Multimode optical modules, or multimode transceivers, operate over MMF which uses a much bigger core and usually uses a longer wavelength of light. Thus, the optics used in MMF has a higher capability to gather light from the laser, for short distance transmission, with distance reach ranging from 100m to 500m. 10GBASE-SR is one of the most widely-used multi-mode transceiver types, such as AFBR-703SDZ-IN2. This Avago Intel compatible 10GBASE-SR SFP+ transceiver listed in FS.COM works over MMF with 850nm laser light for 300m distance reach.

AFBR-703SDZ-IN2, 10GBASE-SR SFP+ fiber optic module

According to Data Rate & Power Supply Standard
  • The connection between two network devices is realized with the help of protocols. It is imperative to know which protocol and data rate the switch or router supports. There are various protocols such as Ethernet, Fiber Channel (FC), InfiniBand, SONET/SDH, CPRI and so on. Each of these protocols supports their own data rates. For example Gigabit Ethernet (GbE) can range from 1Gb/s to 100Gb/s, while FC ranges from 1GFC (1.0625Gb/s) to 16GFC (14.025Gb/s).
  • As for power supply, there are built-in switching power transceiver and eternal power supply transceiver. The built-in switching power transceiver is designed for the carrier grade power. It supports equipment power protection, filters, and a wide power supply voltage regulator, reducing the external point of failure arising from the mechanical contact. By contrast,the external power supply transceiver is made for multi-use civilian equipment, and it is compact and cheap.
  • Of course, the classification standards of fiber optic module is not limited to those three points mentioned above. Other standards are also workable, such as the network management standard. It’s known that there are managed optical modules and unmanaged optical modules. The former type allows additional network monitoring with fault detection, free from configuration function. By contrast, the latter, without monitoring function, allows automatic communication of the devices that are connected to unmanaged optical modules.

When your networking projects call for fiber optic module for fiber optic links, these classification standards will work, since they help you to choose the right fiber optic modules for applications to ensure the reliable data transmission. FS.COM offers an ocean of fiber optic modules which are fully compatible with major brands, including the Brocade E1MGTX, and Avago Intel AFBR-703SDZ-IN2 mentioned above.

The Evolution of 10GbE Cabling Technologies

Since Ethernet technology is born in 1970s, it has evolved continuously to meet the never-ceasing demands of even faster rates of data transmission, such as 10 Gigabit Ethernet (GbE). Along with this ongoing evolution, the cabling technologies that support the 10GbE applications have also advanced, so as to provide greater bandwidth to transmit data with reasonable cost and decreased complexity. Maybe you have few insights in this evolution. Don’t worry. This text mainly talks about the evolution of 10GbE cabling technologies, including fiber and copper cabling technologies.

The Institute of Electrical and Electronics Engineers (IEEE) 802.3 working group has published several standards regarding 10GbE, including 802.3ae-2002 (fiber -SR, -LR, -ER), 802.3ak-2004 (CX4 copper twin-ax InfiniBand type cable), etc. Actually, the evolution of cabling technologies have walked in step with that of 10GbE standards, especially associated with the difference between IEEE802.3ae and IEEE802.3ak standards.


Ratified in June 2002, the IEEE802.3ae standard outlined the following port types.

10GBASE-SR—It supports 10GbE transmission over standard multi-mode fiber (MMF) with distances of 33m on OM1 and 86m on OM2. Using 2000 MHz/km MMF (OM3), up to 300-m link lengths are possible. Using 4700 MHz/km MMF (OM4), up to 400 meter link lengths are possible. Like SFP-10G-SR-S (shown below), this Cisco 10GBASE-SR module listed in Fiberstore is able to support up to 300m using OM3 at the maximum data rate of 10.3125Gbps. In addition, SR is the lowest-cost optics (850nm) of all defined 10GbE optics.

SFP-10G-SR-S, supporting 300m link length using OM3

10GBASE-LR—This port type uses higher cost optics (1310nm) than SR and requires more complex alignment of the optics to support 10km link length over single-mode fiber (SMF).

10GBASE-ER—It’s a port type for SMF and uses the most expensive optics (1550nm) lasers, enabling a reach of 40km over engineered links and 30km over standard links.


Approved in February 2004, this IEEE802.3ak standard only defined 10GBASE-CX4—the first 10GbE copper cabling standard.

10GBASE-CX4—It’s a low-cost 10GbE solution intended for copper cabling with short-distance connectivity. Its affordability and wide availability makes 10GBASE-CX4 ideal for wiring closet and data center connectivity.

The CX4 standard transmits 10GbE over four channels using twin-axial cables which originated from Infiniband connectors and cable. The CX4 standard committee defined that the cables should be tighter in electrical specifications. Therefore, CX4 standard is not appropriate when longer length (>10 Infiniband cable is required. And It’s recommended to use only cables that are designed to meet IEEE 802.3ak specifications.

Another aspect of the CX4 cable is the rigidity and thickness of the cable. The longer the length used, the thicker the cable is. CX4 cables must also be factory-terminated to meet defined specifications.

After comparison between IEEE802.3ae and IEEE802.3ak standards, here goes a picture about the cabling cost and distance considerations.

 cabling cost and distance considerations

Besides IEEE802.3ae and IEEE802.3ak standards, there also exists IEEE802.3an standard. Proposed in November 2002, IEEE802.3an defined 10GBASE-T using unshielded twisted-pair (UTP) style cabling. The goal of this copper standard is to improve the performance and distance of copper cabling at a cost that is lower or similar to fiber.

From the above introduction, the evolution of cabling technologies is associated with the evolution of 10GbE standards. As 10GbE deployment becomes a commonplace, it’s of great importance to make wise cabling strategies.


Spurred by the demand for faster application speeds, cabling technologies evolved to support the 10GbE standards, thus to better accommodate bandwidth-intensive applications and traffic types. With 10GbE technology being pervasive, it’s necessary to understand the the different 10GbE standards and cabling technologies (mentioned above). Fiberstore supplies 10GbE application solutions, transceivers, copper and fiber cables all included, like AFBR-703SDZ-IN2, a 10GBASE-SR SFP+ transceiver. For more information about 10GbE system solutions, you can visit Fiberstore.