Optical Transceiver Interoperability and Compatibility Guide

Posted on March 18, 2020
July 4, 2020
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Countless compatible fiber optic transceivers have been employed in network deployments. However, there still exists the concerns about the quality, interoperability, and compatibility issues when choosing the optical transceivers. A wise selection is of great significance in today's crowded OEM-compatible transceiver market. Will the optical transceivers I purchased work smoothly with my other modules? Will the modules be compatible and operate flawlessly on my switches? This article will lead you to figure out the interoperability and compatibility nature of the optical transceivers.

How to Ensure Interoperability Between Two Optical Transceivers?

When it comes to the connection between two fiber optic transceivers, the following four factors should be taken into considerations: wavelength, speed, fiber type, and the connection to switches.

Prerequisite 1: Identical Wavelength

In a fiber link, the data is transmitted from one end to another, and fiber transceivers are responsible for electrical signals into optical signals and vice versa. Therefore, the optical transceivers should support an identical wavelength at both ends in order to realize the process. Specifically speaking, the wavelength of optical transceivers need to be matched on each end. The unmatched wavelength may cause loss and degradation in data transmission. For example, a 1310nm transceiver won't talk to an 850nm transceiver. In addition, the working mode of modules should also be matched at each end. A full-duplex transceiver should be paired with another full-duplex transceiver. The transmission will be unavailable if connecting a full-duplex module with a half-duplex one.

Prerequisite 2: Same Speed

It is likely to mix two modules with similar appearances or insert the same-sized transceiver into the wrong switch port. In these cases, the connection won't be realized as expected or won't work at all. Take 1G SFP and 10G SFP+ for an example. Having the same size, an SFP module can fit seamlessly into the SFP+ port on the switch and vice versa. If you plug an SFP+ module into an SFP port, it will work but the transmission speed will be limited at 1 Gbps. Contrariwise, when an SFP module is inserted into an SFP+ port, it will fail to connect. As a result, most fiber optic transceivers with different speeds can't cooperate with each other. 10GBASE-T module is an exception that can support 1000Mbps, 2.5Gbps, 5Gbps, 10Gbps by using Cat5e/Cat6/Cat6a cables.

Prerequisite 3: Correct Fiber Type

After possessing the above-mentioned conditions—not to mix up the supporting wavelengths and the speed of the two optical transceivers, selecting the corresponding fiber cables is also critical. Normally speaking, multimode fiber optic cables can be classified into OM1, OM2, OM3, OM4, and OM5 fiber types, and all of them are used for short-range transmission. If a module is connected with OM1/OM2 fibers, while the other one is connected with OM3/OM4 fibers, then the connection won't be succeeded. Identifying them through the standardized colors on the outer jacket of fibers may help. Read Multimode Fiber Types: OM1 vs OM2 vs OM3 vs OM4 vs OM5 to learn more about their differences. If the correct fiber type is adopted, the connector types won't be restricted. An SC on one end and an LC on the other end is feasible.

Prerequisite 4: Flawless Operation on Switches

The aforementioned conditions have made a firm foundation for the following in-field experiment. On the one hand, make sure that the compatible modules that you purchased have been tested on the original-brand switches. For instance, a Cisco compatible fiber optic transceiver must be tested on Cisco switches to avoid abnormal operations. On the other hand, figure out that your devices will support the modules you want to use. Because the switches of some brands are not compatible with the modules from other vendors effortlessly.

Connection to the Switch.jpg

How to Ensure Optical Transceiver Compatibility?

The first and foremost requirement for an optical transceiver to operate perfectly on network switches is—compatibility. As mentioned in the last part, some of the industry manufacturers will encrypt their devices, which may increase the difficulty of the module compatibility. To make sure a third-party transceiver can work on the OEM switch, choosing a reliable vendor with a rigorous testing system for transceivers is crucial.

An Elaborate Testing System

The testing system can be roughly divided into twofold: test for the semi-finished modules & test for the finished modules. The former can be further separated into basic appearance inspection (accessories, packaging, craft, etc.) and parametric performance tests. The latter has various testing items including optical power tests, spectral tests, eye diagram tests, digital diagnostic function tests, high and low temperature tests, etc. The finished modules will be double-checked of the outlook and have the switch connection tests for DDM, compatibility, and connectivity results. For compatibility tests, the compatible modules will be tested on the OEM switches. Consequently, conducting a series of rigorous tests of compatible transceivers can guarantee flawless operations on devices like switches.

Tests for Optical Transceivers.jpg

A Trustworthy Third-party Supplier

How to evaluate a third-party supplier? Firstly, the overall qualification assessment. A reliable third-party compatible supplier requires the investment of comprehensive equipment like switches and servers, the capabilities of the testing environment, an abundance of experienced staff, and the thorough documentation of the testing parameters and results. Besides, the compatibility issue will trouble many users. Therefore, maintenance and other after-sale services are critical. A professional staff team is also required to answer technical consulting if there is something wrong with the compatible modules.

FAQs

Will two optical transceivers from different brands/vendors connect with each other?

If the wavelength, the speed, and the fiber type of the modules are the same, plus operating normally on the original switches separately, then adopting two modules from different brands will work.

Can I use 1G SFP and 10G SFP+ modules together?

The answer is yes. Under the condition that both of them are sharing the same specifications like speed and wavelength and choosing the corresponding fibers. Note that, the transmission speed will be restricted at 1G instead of 10G.

If I pick compatible modules, will they affect the performance of my OEM switches?

MSA standards ensure that all the optical transceivers adhere to defined specifications. If the compatible modules are built to the same standards as the OEM's self-produced ones, then they won't impact the host systems' performance.

Will the compatible fiber optic transceivers invalidate my warranty with the vendor branded switches?

No, adopting compatible modules won't void any warranty. Vendors can't demand that only their original parts may be used with their OEM systems to retain the warranty.