In optical transport networks (OTNs), wavelength division multiplexing (WDM) technology has been warmly welcomed by network users. It is a technology that multiplexes multiple optical carrier signals of different wavelength lasers on a single optical fiber. By using WDM technology, SFP optical modules can allocate different wavelengths. There are two main types of wavelength division multiplexing (WDM) systems: coarse wavelength division multiplexing (CWDM) and dense wavelength division multiplexing (DWDM). But what are the differences between DWDM transceiver module and CWDM optical transceiver?
CWDM optical module is an optical transceiver using CWDM technology. It is similar to a traditional SFP module and supports hot-plugging. CWDM SFP optical transceiver can be inserted into the SFP port or slot of the switch or router to connect the port to the optical fiber network. The appearance of CWDM SFP optical module is shown in the figure below.
As we all know, CWDM optical module has 8 type of wavelengths, ranging from 1470nm to 1610nm. According to the 8 different wavelengths, 8 different colors of optical modules are designed. For example, the wavelength of the optical module with purple pull ring is 1490nm, and the wavelength of the optical transceiver with yellow pull ring is 1550nm, so we can identify fiber optical modules with different wavelengths according to the color of the pull ring.
DWDM (Dense Wavelength Division Multiplexing) SFP fiber optic module is a dual-fiber bidirectional 10G optical module that can provide high-capacity bandwidth in the network and has 32 fixed wavelengths that can support the International Telecommunication Union (ITU) 100 GHz wavelength.
The channel spacing of DWDM SFP optical modules has different spacing such as 0.4nm, 0.8nm, 1.6nm, etc. according to the needs. Its spacing is small, so additional wavelength control devices are required, and the cost will be higher. However, DWDM SFP optical modules have a key advantage, that is, its protocol and transmission speed are irrelevant.
CWDM optical module is widely used in point-to-point networks of Gigabit Ethernet and Fiber Channel network equipment in telecommunications and data centers. DWDM optical module is mainly used in long-distance optical synchronous digital transmission networks, such as Ethernet/Fiber Channel with 80km to 200km.
From a cost perspective, CWDM transceiver module is cheaper than DWDM fiber optical module. CWDM optical module provides a convenient and low-cost solution for adopting Gigabit Ethernet and Fiber Channel.
On the other hand, DWDM usually uses denser channel spacing and is used in large optical networks with longer distances. If you are looking for SFP modules for long distances and want better scalability, DWDM fiber module is an ideal choice.
CWDM SFP optical module is a multi-rate optical module with transmission distances of 20km to 40km, 40km to 80km and 80km to 120km. Different colors mark optical modules with different wavelengths, which can better meet customer requirements. UnitekFiber is an experienced professional fiber networking solution provider, providing all kinds of fiber optic transceiver, media converter, fiber optic patch cord or fiber optic patch panel for data center. UnitekFiber has got you covered. For any inquiries or further information, please don't hesitate to reach out to us at sales@unitekfiber.com