With the rapid development of domestic and international networks, 10G Ethernet will soon replace Gigabit Ethernet, and at the same time, 10G SFP+ optical modules will be more widely used in various network scenarios. The purpose of this article is to provide a brief introduction to 10G SFP+ optical modules, so that readers can have a clear categorization of 10G SFP+ optical modules.
10G SFP+ optical module is a kind of optoelectronic conversion module with transmission rate of 10G, encapsulation mode of SFP+, conventional wavelength of sfp+ 850nm/1310/1550, fiber optic interface of LC interface, and transmission distance ranging from 300m to 120km. 10G SFP+ optical module is connected with LC interface, inserted into switches, servers and other equipment, to complete the conversion of optoelectronic signals to each other. The compactness of 10G SFP+ optical modules makes them widely used in data centers, enterprise networks, metro networks and other network applications. This article will introduce 10G SFP+ optical modules in detail from several dimensions.
SFP: Small Form-factor Pluggable
From a superficial perspective, SFP+ module appears to be an upgraded version of SFP. However, in practical usage, they are quite similar in size and appearance, but correspond to different rates of optical modules. SFP packaging corresponds to hundred-megabit and gigabit optical modules, while SFP+ corresponds to ten-gigabit optical modules. Generally, the anti-static shielding of the SFP+ optical module housing produced by manufacturers is superior to that of SFP optical modules, and in terms of quality, SFP+ is much better than SFP optical modules. However, in everyday communication, some customers also refer to ten-gigabit optical modules as 10G SFP optical modules.
Each major category of optical modules has specific definitions from the perspective of transmission distance. For example, for 10G SFP+ optical modules, they can be defined as 10G SR, 10G LR, 10G ER, and 10G ZR based on the transmission distance.
10G SR optical modules are the most common type among 10G SFP+ optical modules. SR stands for short reach and is used with OM3 multimode fiber (MMF), capable of transmitting up to 300 meters. 10G SR multimode optical modules use VCSEL lasers, which have significant advantages in cost and power consumption. Some equipment vendors classify 10G SR multimode optical modules as 10G SRL, which stands for 10G SR lite, but they are essentially the same product.
10G LR optical modules are one type of 10G SFP+ single-mode optical modules. LR stands for long reach and uses a 1310 wavelength, capable of transmitting up to 20km over single-mode fiber. 10G LR optical modules use DFB lasers, and their cost has gradually decreased with increasing usage. Additionally, in 10GBASE-LRM, LRM stands for long reach multimode, mainly used for short-distance local area network connections up to 220 meters.
10G ER optical modules are the first type of optical modules designed for long-distance transmission in 10G SFP+. ER stands for extensive reach and operates at a wavelength of 1550nm, capable of transmitting up to 40km over single-mode fiber. These modules use EML lasers for modulation, providing greater stability.
10GBASE-ZR optical modules operate at the same wavelength as ER, which is 1550nm, but can transmit over longer distances, up to 80km over single-mode fiber. Some manufacturers have improved lasers to extend transmission distances up to 120km, but these are not widely available in the market.
Currently, there are two common interfaces for 10G optical modules on the market: one is the LC interface, and the other is the RJ45 interface. The aforementioned 10GBASE-SR, 10GBASE-LR, 10GBASE-ER, and 10GBASE-ZR are all typically LC interfaces. The optical modules applied with RJ45 interfaces are 10G copper port optical modules, known as 10GBASE-T COPPER RJ45.
The wavelength of 10GBASE SFP+ optical modules for 10G networks typically includes three types: 850nm, 1310nm, and 1550nm. Each of these wavelengths corresponds to different transmission distances for 10G optical modules. The 850nm wavelength is used in 10GBASE-SR SR multimode optical modules, with a transmission distance of up to 300 meters. The 1310nm wavelength is applied in 10GBASE-LR long-reach multimode optical modules, capable of transmitting up to 20km. The 1550nm wavelength is utilized in 10GBASE-ER and 10GBASE-ZR long-distance multimode optical modules, with a maximum transmission distance of 120km.
From the classification of 10G optical modules in the preceding text, it is clear that 10G optical modules have become quite mature products. With the widespread promotion and adoption of 10-gigabit Ethernet, 10G optical modules will be applied more extensively. Consequently, their production costs will decrease significantly, resulting in substantial savings for customers.
