Taking an In-depth Look at DWDM Transceivers

Updated on Jul 22, 2020 by

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It is no exaggeration to say that the advent of DWDM technology has almost changed the landscape of optical networks. With DWDM transceiver being one of its most important components, DWDM network has been widely employed in many different industries and areas to boost network capacity.

What Is DWDM Transceiver?

The DWDM transceiver integrates Dense Wavelength Division Multiplexing (DWDM) technology into an optical transceiver platform. It facilitates the multiplexing of multiple optical signals onto a single fiber using different wavelengths, optimizing fiber usage without requiring additional power. These transceivers are engineered for high-capacity, long-distance transmissions, supporting speeds up to 100 Gbps and extending transmission distances of up to 120 kilometers. Compliant with Multi-Source Agreement (MSA) standards, DWDM transceivers ensure compatibility across a wide range of network equipment.

How Does DWDM Transceiver Work?

DWDM transceiver functions just as other standard optical transceivers - to convert electrical signal to optical signal and then to electrical signal. The difference is that DWDM transceiver leverages DWDM technology to multiplex different wavelengths or several optical signal onto a single fiber to save valuable fiber resources. It is designed for single-mode fiber and operates at a nominal DWDM wavelength from 1528.38 to 1563.86 nm (Channel 17 to Channel 61) as specified by the ITU-T. Except from being applied in long distance transmission, DWDM transceivers can also be used in switch to switch interface, switched backplane applications and router/server interface etc.

the working principle of dwdm transceiver

Figure 1: DWDM Transceiver Working Principle

Common DWDM Transceiver Types

DWDM transceivers are available in different types, supporting transmission rate from 155 Mbit/s to 10 Gbit/s. Categorized by data rates and form factors, there are SFP DWDM transceiver, DWDM SFP+ transceiver, DWDM XFP transceiver, etc. as following.

Product	Description
DWDM SFP	DWDM SFP transceivers provide a high-speed serial link at signaling rates from 100 Mbps to 2.5 Gbps. The DWDM SFP modules meet the requirements of the IEEE802.3 Gigabit Ethernet standard and ANSI Fibre Channel specifications, and are suitable for interconnections in Gigabit Ethernet and Fibre Channel environments.
DWDM XENPAK	DWDM XENPAK is an important step in the evolution. It is the first 10GbE transceiver ever to support DWDM. DWDM XENPAK transceiver supports 32 different channels for up to 200 km with the aid of optical amplifiers known as EDFAs.
DWDM X2	DWDM X2 transceiver is a high performance, serial optical transponder module for high-speed, 10G data transmission applications. The optical module is fully compliant to IEEE 802.3ae standard for Ethernet, making it ideally suited for 10GbE datacom applications.
DWDM XFP	DWDM XFP transceiver complies with the current XFP MSA specification. It supports SONET/SDH, 10GbE and 10-Gigabit Fibre Channel applications. It is small in size and cheap in price.
DWDM SFP+	DWDM SFP+ is specifically designed for carriers and large enterprises that require a scalable, flexible, cost-effective network system. It is even smaller than the previous XFP and is the ideal choice for 10G highest-bandwidth application.

dwdm transceiver

Figure 2: DWDM Transceiver Evolvement

Wavelength Flexibility: Fixed vs. Tunable DWDM Transceivers

After covering the common types of DWDM transceivers, it's essential to address another key aspect: their wavelength flexibility. This characteristic is critical as it determines how these devices can be optimized for various network setups and applications.

Fixed Wavelength DWDM Transceivers

Fixed wavelength Dense Wavelength Division Multiplexing (DWDM) transceivers are designed to operate at specific and unchangeable wavelengths as dictated by the International Telecommunication Union (ITU) grid standards, such as the commonly used 1310nm and 1550nm wavelengths. These transceivers are particularly well-suited for network environments where channel allocation is static and well-defined. Their deployment is straightforward, as each transceiver is pre-configured for its designated wavelength, thereby eliminating the need for tuning during installation.

Tunable DWDM Transceivers

Unlike fixed wavelength transceivers, tunable DWDM transceivers offer the capability to dynamically select and adjust to any wavelength within the C-Band 50 GHz spectrum. This ability encompasses around 88 distinct channels with 0.4 nm spacing. Such transceivers are indispensable in scenarios that demand versatility and adaptability, such as rapidly changing network conditions or for application as spare modules in the event of equipment failure, thus ensuring robust and resilient network operations.

If you want to delve deeper into tunable DWDM Transceivers, you can check out this article: A Comprehensive Understanding of Tunable DWDM Transceiver.

Conclusion

In conclusion, DWDM technology has revolutionized optical networks by maximizing bandwidth efficiency and extending transmission distances, thanks to the versatility of DWDM transceivers. Whether utilizing fixed wavelength transceivers for stable, predefined channel allocations or opting for tunable transceivers for dynamic wavelength adjustments, these devices play a pivotal role in modern telecommunications, data centers, and other high-demand environments. As the demand for high-speed, long-haul optical solutions continues to grow, FS remains at the forefront, offering a comprehensive range of DWDM transceivers including DWDM SFP, DWDM SFP+, and DWDM SFP28 modules, ensuring seamless integration and robust performance in diverse network infrastructures.