Leveraging 25G CWDM Transceivers in 5G Fronthaul Networks

What is a 25G CWDM Transceiver?

The 25G CWDM transceiver plays a crucial role in modern telecommunications, particularly in 5G fronthaul networks. Operating at 25 Gbps, it utilizes CWDM technology to transmit multiple signals over one fibre, optimising bandwidth. Specifically designed for 5G fronthaul, it supports 25G Ethernet and CPRI/eCPRI, with impressive 10km link distances over single-mode fibre. Fully compliant with SFP28 MSA, CPRI, and eCPRI standards, it typically operates within the wavelengths of 1270nm-1370nm and 1470nm-1570nm.

If you want to know more about the differences between the 25G CWDM module and other 25G SFP28 modules, you can check out this article: 25G SFP28 Transceiver Module Overview.

 Figure 1: FS CWDM SFP28 Transceiver

What is the 5G Transport Network?

The 5G transport network encompasses fronthaul, midhaul, and backhaul, connecting cell sites with one another, then with the core network, and ultimately with data centres.


As 5G technology continues to evolve, the significance of “fronthaul” in the telecommunications industry is on the rise. This fiber-based link, integrated within the Radio Access Network (RAN) infrastructure, plays a pivotal role in achieving faster speeds and reduced latency. With the introduction of Distributed RAN (DRAN) and Centralized RAN (CRAN) approaches, base station components such as the Central Unit (CU), Distributed Unit (DU), and Active Antenna Unit (AAU) are undergoing substantial restructuring to meet evolving requirements. Fronthaul acts as the vital connection between the active antenna unit (AAU) and the distributed unit (DU), ensuring smooth communication and efficient data transmission. Innovations like the 25G CWDM SFP28 transceiver are essential for facilitating seamless communication and efficient data transfer across 5G fronthaul networks.


Midhaul is a vital element of the telecommunications network, acting as the intermediary between the fronthaul and backhaul segments. It encompasses the transmission path from the Distributed Unit (DU) to the Centralised Unit (CU). In the context of 5G networks, base stations are structured into a distributed architecture. Here, the DU oversees the transmission and reception of wireless signals, while the CU manages communication with the core network. Acting as a pivotal link between these two units, midhaul facilitates the transfer of data from the DU to the CU for further processing and dissemination across the network.


In addition to fronthaul and midhaul, the 5G transport network also includes the backhaul. This component consolidates access to traffic from the Radio Access Network (RAN) and utilises various technologies such as Ethernet, microwave, and optical fibre to transport it to the central office or data centre. The backhaul serves as a crucial link, connecting the fronthaul and midhaul to the core network, facilitating seamless data transmission across extensive distances.

Figure 2: 5G Transmission Networks Architecture

Utilisations of 25G CWDM Transceivers

In the initial stages of setting up 5G networks, fronthaul predominantly relies on direct fibre links, along with extensive coverage of both high-frequency and low-frequency spectrums for additional access points. To optimise the utilization of existing fibre resources, CWDM optical modules play a crucial role. The 25G CWDM solution allows for the selection of 6 or 12 wavelengths from the 18 specified in the ITU-T G.694.2 standard, spanning from 1271nm to 1611nm. Adhering to this standard enables optical transmission equipment from various vendors to operate harmoniously within the same network, ensuring network stability and reliability while mitigating issues stemming from equipment mismatches.

  • 25G CWDM SFP28 6-Wavelength Solution

The 6-wavelength 25G CWDM solution opts for the initial 6 shorter wavelengths (1271nm~1371nm) due to the maturity of the industry chain and the lesser impact of transmitter dispersion penalties (TDP). It’s widely agreed upon that the AAU side utilizes wavelengths of 1271nm, 1291nm, and 1311nm, while the DU side employs wavelengths of 1331nm, 1351nm, and 1371nm, as depicted in Fig.3. Additionally, the optical module on the AAU side requires cooled directly modulated lasers (DMLs) to meet industrial-grade standards.

Figure 3: 25G CWDM SFP28 6-Wavelength Solution
  • 25G CWDM SFP28 12-Wavelength Solution

The 12-wavelength 25G CWDM solution addresses a mixed transmission scenario involving both 4G and 5G networks. To enhance reliability and reduce component costs, the wavelengths ranging from 1271nm to 1371nm operate at a 25Gbit/s data rate for 5G fronthaul networks, while the wavelengths from 1471nm to 1571nm operate at a 10Gbit/s data rate for 4G fronthaul networks. This arrangement, illustrated in Fig. 4, facilitates the smooth transition from 4G to 5G base stations. However, in practice, the 25G SFP28 connector takes precedence due to its compatibility with both 4G and 5G networks, making the 12-wavelength solution less commonly used in real-world scenarios.

Figure 4: 25G CWDM SFP28 12-Wavelength Solution

Benefits of 25G CWDM Transceivers

  • Cost-effectiveness CWDM technology enables the transmission of multiple signal wavelengths over the same fibre optic cable, efficiently utilising fibre optic resources. With 25G CWDM optical modules, multiple data streams can be transmitted over a single fibre optic cable without the need for additional fibres, thus conserving fibre optic resources and reducing network construction costs.
  • Flexibility and Scalability Given the significant and ever-growing volumes of data typically associated with big data applications, networks must possess robust flexibility and scalability. By utilising 25G CWDM modules, users can dynamically select different wavelengths for data transmission, enhancing the adaptability and scalability of the network to meet the continuously expanding demands of big data processing.
  • Data Security In the realm of big data applications, the handling and processing of extensive volumes of sensitive data are routine, emphasising the critical importance of data security. 25G CWDM modules enhance data transmission security by segregating data streams of varying wavelengths into separate channels. This segregation reduces the risks of data leaks and interference, thereby enhancing the reliability and security of data transmission.


In brief, the 25G CWDM SFP28 is a critical optical transceiver that efficiently sends multiple signals down a single fibre optic cable using CWDM technology. It plays a pivotal role in providing effective data transmission solutions for 5G fronthaul networks. This technology not only optimizes how bandwidth is used but also meets the high-speed and low-latency demands of 5G networks. Moreover, it enhances data transmission security by segregating data streams into separate channels based on different wavelengths. Overall, its use ensures comprehensive protection for network performance, flexibility, and security, laying a solid foundation for the future of 5G communication.

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Overview of Dual Rate 10/25G Transceiver Module

In the realm of network communications, the increasing demands for data processing have posed a challenging task for many enterprises: integrating high-speed, stable, and flexible data transmission solutions. This article will explore a solution that not only addresses the requirements of modern data centres but also considers cost efficiency—dual rate 10/25G transceiver module. With its versatility and economic viability, the dual rate module signifies a strategic amalgamation of performance and scalability ideally suited for the evolving landscape of network infrastructure.

What is Dual Rate 10/25G Transceiver Module?

The dual rate 10/25G transceiver module is a form of optical transceiver capable of accommodating two distinct data rate options: 10 gigabits per second (Gbps) and 25 Gbps. Its design allows seamless interoperability with network equipment, dynamically adjusting between these speeds based on the connected devices’ capabilities and the network’s requirements.

These dual rate modules provide a high level of flexibility for network infrastructure, eliminating the need for multiple types of transceivers. This significantly simplifies the management of network upgrades and inventory, as the same module can be employed across various network segments operating at either 10Gbps or 25Gbps speeds.

Practically, a dual rate module typically adopts a form factor like SFP28 (small form-factor pluggable 28), commonly utilized in 25Gbps networking but also compatible with 10Gbps, ensuring backward compatibility with older equipment. This empowers IT managers to future-proof their networks and facilitates an upgrade path from 10G Ethernet to 25G Ethernet without necessitating a complete overhaul of the existing cabling infrastructure.

The dual rate functionality proves particularly advantageous for data centres striving to optimize bandwidth, manage costs efficiently, and prepare for escalating data traffic demands, all while maintaining compatibility with existing 10G network equipment.

Applications of Dual Rate 10/25G Transceiver Module

The dual rate 10/25G transceiver module is an optical transceiver that can operate at two different data rates, 10 Gbps and 25 Gbps. This versatility allows the module to be used with a wide range of networking equipment and in various scenarios to meet the demands of modern data centres and enterprise networks. Here are some applications where a dual rate 10/25G transceiver module may be particularly beneficial:

Transitioning to 25G Network via Dual Rate 10/25G Transceiver Module

Businesses transitioning from 10G to 25G networks can employ dual rate modules to ensure seamless compatibility throughout the process, facilitating a gradual migration and minimising downtime. Data centres requiring high-bandwidth connections between servers, storage systems, and network switches can benefit from the increased data rates of 25G, while dual rate capability ensures compatibility with existing 10G equipment.

Optimising High-Density Networks

In high-density network environments where rack space is limited, dual rate modules can optimise port density and reduce space requirements by allowing connection consolidation and gradual speed upgrades. Enterprises needing a mix of 10G for legacy devices and 25G for newer, high-throughput applications can utilise dual rate 10/25G transceiver modules for flexible connectivity options.

Enhancing Hybrid Cloud Environments

Organisations operating within hybrid cloud environments can employ dual rate transceivers to facilitate efficient data transfer between different network segments operating at varying speeds. This flexibility enables seamless integration between on-premises and cloud infrastructures.

Versatile Solutions for Telecom Networks

Telecom operators and service providers can leverage dual rate modules to offer customers a range of services operating at either 10G or 25G, providing adaptable solutions tailored to diverse requirements and network demands.
Essentially, dual rate 10/25G transceiver modules assist in offering flexibility, scalability, and investment protection for network infrastructure. They enable network managers to balance performance requirements with budget constraints, and they can be a strategic option for phased network upgrades, ensuring compatibility between different generations of networking equipment.

Introducing FS Dual Rate 10/25G Transceiver Module

FS dual rate modules have earned high acclaim in the market owing to their outstanding reliability, excellent compatibility, and effective cost management. These modules are distinguished as the preferred option for enhancing network performance and efficiency. Below is a parameter comparison of FS dual rate 10/25G transceiver module FS 10/25G dual rate module.


With the continuous evolution of network technology and the growing demand for flexibility in data centres, dual rate 10/25G transceiver modules are poised with immense potential. Offering a cost-effective solution, they address the challenges of rate adaptability and future compatibility, making them a wise choice for constructing advanced and dependable network infrastructure.

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Migrate to 25G Network With 10/25G Dual Rate Transceiver

The rapid adoption of the 10G-25G upgrade path has spurred the development of 10/25G dual rate fiber optics, offering a simpler solution to accommodate the prevailing migration trend in contemporary Ethernet networks.

Challenges in Transitioning from 10G to 25G Network
25Gbps has been deemed a cost-effective and minimally disruptive method for upgrading from 10Gbps to the higher speed of 100Gbps by numerous forward-thinking enterprises and data centres. Over recent years, there has been a remarkable surge in the 25Gbps market and the technological significance of deploying 25G networks. Nonetheless, the transition from 10G to 25G may present supplementary challenges.
The commonly utilised transceiver modules typically support a single rate, such as 10G SFP+ transceivers and 25G SFP28 transceivers. Given that both ends of a 10G-25G link necessitate simultaneous upgrading, transitioning from 10G to 25G networks entails replacing the entire transceiver and cable infrastructure, leading to significant costs in capital expenditure, time, and energy.
To tackle the challenges encountered in the migration path from 10G to 25G, dual-rate transceivers supporting both 10G and 25G are being introduced.

10/25G Dual Rate Transceiver – Solution to 10G-25G Network
Dual-rate transceivers, often referred to as multi-rate transceivers, denote a type of optical transceiver that supports dual rates, as opposed to the commonly used single-rate transceivers. As the name suggests, 10/25G dual-rate transceivers accommodate two rates – 10Gbps and 25Gbps. In terms of appearance, the dual-rate transceiver resembles a 25G single-rate transceiver – both conform to the SFP28 form factor.
However, the dual-rate transceivers are compatible with either 10G SFP+ ports or 25G SFP28 ports, making them more versatile than single-rate transceivers. Furthermore, when employed with a breakout cable, they have the capability to operate with 40G/100G networks.
The ensuing chart will juxtapose 10/25G dual rate optical transceivers with 10G/25G single-rate transceivers, utilizing the FS 10/25GBASE-SR transceiver as a reference.

Transceiver TypeMax. Data RateMax. Cable DistanceClock and Data Recovery (CDR)Compatibility With SFP+ PortCompatibility With SFP28 Port@10GCompatibility With SFP28 Port@25G
10/25G SR Transceiver10Gbps and 25.78Gbps100m @ OM4 MMF, 70m @ OM3 MMFTX & RX Built-in CDR SupportedYYY
10G SFP+ SR Transceiver10.3125Gbps400m@OM4 300m@OM3NYYN
25G SFP28 SR Transceiver25.78Gbps100m @ OM4 MMF, 70m @ OM3 MMFTX & RX Built-in CDR SupportedNNY

Apart from dual rate transceivers in SFP28 transceivers, there are also other dual rate transceivers with different form factors and data rates such as dual rate SFP+ transceivers supporting 100M/1000Mbps data rates.

Advantages of 10/25G Dual Rate Transceiver

10/25G dual rate optical transceivers include advantages as follows:

Backwards Forward Compatibility

As previously mentioned, 10/25G dual rate transceivers are compatible with either 10G SFP+ ports or 25G SFP28 ports. They can be configured to operate at either 10G or 25G, depending on the switch ports’ support.

Future-Proofed Networking

For those deploying a 10G network without an immediate need to upgrade to 25G, utilizing dual rate SFP28 transceivers future-proofs the network. This makes it easier to upgrade the network whenever necessary without requiring new infrastructure.

Protection of Investments

The functionality of a 10/25G dual rate transceiver combines that of a 10G SFP+ transceiver and a 25G SFP28 transceiver. There is no need to change cables or transceivers when upgrading from 10G to 25G network, thus minimizing upgrade costs. Moreover, for network operators reluctant to upgrade the entire 10G network infrastructure at once, dual rate transceivers present a cost-effective solution.

Streamlined Network Upgrades

Implementing 10/25G dual rate transceivers eliminates the complexity associated with changing transceiver modules and cables. This saves significant time and effort for network operators, particularly in high-density data centres where altering a wide range of deployments can be cumbersome.

Dual Rate Transceiver Application for 25G Network

10/25G dual rate transceivers can be used to replace single rate 10G or 25G transceivers in data centres or enterprises, connecting distribution switches to access switches, ToR, MoR, EoR switches to servers or leaf switches based on the transmission distance they allow.

As the figure shows, when the switches are upgraded from 10G to 25G switches, the dual rate transceivers and cables need no change or addition, which helps to upgrade from 10G network to 25G network seamlessly. Whether in data centres or enterprises, when network operators are deploying 10G networks but require future migration from 10G to 25G, the 10/25G dual rate transceiver can help the deployment with its 10G/25G dual rate capability.

FS.com supports 10G/25G dual rate transceiver portfolio and network switches that support dual rate transceivers such as S5860-20SQ switch with 10G/25G SFP28 dual rate ports for multiple uses in 10G or 25G Ethernet networks.

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25G Ethernet–A New Trend for Future Network

As the demand for bandwidth in Cloud data centres is experiencing a notable surge, the networking and Ethernet industries are pivoting towards a fresh direction, namely 25G Ethernet. It appears that 25GbE holds greater favour and adoption among end users when juxtaposing upgrade paths of 10GbE-25GbE-100GbE and 10GbE-40GbE-100GbE. What prompts the selection of 25GbE? What advantages does it offer? This tutorial will comprehensively elucidate the merits of 25G Ethernet.

The Emergence of 25G Ethernet

Network engineers were once taken aback by the notion of a 10GbE link. However, virtualisation and cloud computing have introduced fresh networking challenges necessitating greater bandwidth. Top of Rack (ToR) switches, commonly boasting the highest number of connections in data centres, are swiftly surpassing the capabilities of 10GbE. Subsequently, the IEEE sanctioned standards for 40GbE and 100GbE to meet these demands. Nevertheless, 40GbE proves to be less cost-effective and power-efficient in ToR switching for cloud providers, while the deployment of 100GbE remains comparatively arduous and expensive.

Against such a backdrop, the 25G Ethernet standard was developed by the IEEE 802.3 Task Force P802.3by, designed for Ethernet connectivity to enhance Cloud and enterprise data centre environments. The 25GbE specification utilises single-lane 25Gbps Ethernet links and is founded on the IEEE 100GbE standard (802.3bj), achieving 100GbE through 4x25Gbps lanes.

25G Ethernet Optics & Cables

The 25GbE physical interface specification supports two main form factors—SFP28 (1×25 Gbps) and QSFP28 (4×25 Gbps). Commonly used transceivers are 25GbE SFP28.

The 25GbE PMDs (Physical Medium Dependent) specify low-cost, twinaxial copper cables, requiring only two twinaxial cable pairs for 25Gbps operation. Links based on copper twinaxial cables can connect servers to ToR switches, and serve as intra-rack connections between switches and routers. Fan-out cables (cables that connect to higher speeds and “fan-out” to multiple lower speed links) can connect to 10/25/40/50 Gbps speeds, and can now be accomplished on MMF (multimode fibre), SMF (single-mode fibre), and copper cables, matching reach-range to the specific application needs. Commonly used cables are 25GbE DAC and 25GbE AOC.

Physical LayerNameReachError Correction
Electrical Backplane25GBASE-KR1 mBASE-R FEC or RS-FEC
Electrical Backplane25GBASE-KR-S1 mBASE-R FEC or disabled
Direct Attach Copper25GBASE-CR-S3 mBASE-R FEC or disabled
Direct Attach Copper25GBASE-CR5 mBASE-R FEC or RS-FEC
Twisted Pair25GBASE-T30 mN/A
MMF Optics25GBASE-SR70 m OM3 / 100 m OM4RS-FEC
Table 1: Specification of 25GbE Interfaces.

Why Choose 25G Ethernet?

While 10GbE is adequate for many current setups, it lacks the necessary bandwidth efficiency and demands extra devices, substantially raising costs. Additionally, 40GbE isn’t economically viable or power-efficient in ToR switching for Cloud providers. Hence, 25GbE was developed to overcome this dilemma.

Number of SerDes Lanes

SerDes (Serializer/Deserializer) is an integrated circuit or transceiver used in high-speed communications for converting serial data to parallel interfaces and vice versa. The transmitter section is a serial-to-parallel converter, and the receiver section is a parallel-to-serial converter. Currently, the SerDes rate is 25 Gbps. That means only one SerDes lane at 25Gbps is required to connect one end of a 25GbE card to the other end of a 25GbE card. In contrast, 40GbE requires four 10GbE SerDes lanes to establish connections. Consequently, communication between two 40GbE cards necessitates as many as four pairs of fibres. Furthermore, 25G Ethernet offers a straightforward upgrade path to 50G and 100G networks.

Figure 1: Numbers of Lanes Needed in Different Gigabit Ethernet.

More Efficient 25GbE NIC for PCIe Lanes

At present, the mainstream Intel Xeon CPU only provides 40 lanes of PCIe (PCI Express) 3.0 with a single-lane bandwidth of about 8 Gbps. These PCIe lanes are used for not only communications between CPU and network interface cards (NIC), but also between RAID (Redundant Array of Inexpensive Disks) cards, GPU (graphics processing unit) cards, and all other peripheral cards. Therefore, it is necessary to increase the utilisation of limited PCIe lanes by NIC. A single 40GbE NIC needs at least one PCIe 3.0 x8 lane, so even if two 40GbE ports can run at full speeds at the same time, the actual lane bandwidth utilisation is only: 40G2 / (8G16) = 62.5%. On the contrary, a 25GbE NIC card only needs one PCIe 3.0 x8 lane, then the utilisation efficiency is 25G2 / (8G8) = 78%. Clearly, 25GbE is significantly more efficient and flexible than 40GbE in terms of the use of PCIe lanes.

Figure 2: 25G NIC Deployment.

Lower Cost of 25GbE Wiring

40GbE cards and switches utilise QSFP+ modules with relatively costly MTP/MPO cables not compatible with LC optical fibres of 10GbE. If upgrading to 40GbE based on 10GbE, most of the fibre optic cables will be abandoned and rewired, which can be a huge expense. In comparison, 25GbE cards and switches use SFP28 transceivers and are compatible with LC optical fibres of 10GbE due to a single-lane connection. If upgrading from 10GbE to 25GbE, rewiring can be avoided, which turns out to be time-saving and economical.

Distinct Benefits of 25GbE for Switch I/O

Firstly, 25G Ethernet has an excellent maximum switch I/O (Input/Output) performance and fabric capability. Web-scale and Cloud organisations can enjoy 2.5 times the network bandwidth performance of 10GbE. Delivered across a single lane, 25GbE also provides greater switch port density and network scalability. Secondly, 25GbE can reduce capital expenditures (CAPEX) and operating expenses (OPEX) by significantly cutting down the required number of switches and cables, along with the facility costs related to space, power, and cooling compared to 40GbE technology. Thirdly, 25GbE using a single lane 25Gbps Ethernet link protocol leverages the existing IEEE 100GbE standard which is implemented as four 25Gbps lanes running on four fibre or copper pairs.

Future 25G Ethernet Market Forecast

Over the past few years, 25G Ethernet has garnered escalating recognition, with 25GbE products undergoing notable advancements and securing an augmented market share. Anticipations hold that 25GbE will pursue a broader market in 2020 and will continue to flourish in the foreseeable future. Over the long term, 25GbE is forecasted to emerge as a future-proof trend in high-speed data centre networks, owing to the versatility of 25GbE adapters capable of operating at 10GbE speeds.

Additionally, 25GbE switches offer a more convenient pathway for migration to 100G or even 400G networks, circumventing the need for a 40GbE upgrade. Whilst the importance of industry consensus building cannot be overlooked, it is worth noting that currently, 25GbE is predominantly utilised for switch-to-server applications. Should the adoption of switch-to-switch applications be significantly encouraged, the potential for further advancement of 25G Ethernet is evident. In summary, the transition to 25GbE is gaining momentum.


Regardless of market research findings or user attitudes, 25G Ethernet appears to be the favoured choice moving forward, given its lower cost, reduced power consumption, and enhanced bandwidth. Considering the tangible advantages of 25G Ethernet, it is anticipated to continue advancing unquestionably in the future.

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Quick Guide to Buying 10G CWDM/DWDM SFP+ Transceivers

As optical communication technology rapidly advances, 10G CWDM/DWDM SFP+ transceivers have become essential components in modern networking solutions. These transceivers facilitate high-speed data transmission over optical fibres by utilising either Coarse Wavelength Division Multiplexing (CWDM) or Dense Wavelength Division Multiplexing (DWDM) technologies. In this article, we’ll delve into the characteristics and applications of both 10G CWDM and DWDM SFP+ transceivers, aiming to provide insights into which solution best aligns with your specific networking requirements.

Understanding 10G CWDM/DWDM SFP+ Transceivers

10G CWDM SFP+ Transceiver

The 10G CWDM SFP+ transceivers are optical devices designed for efficient data transmission in fibre optic networks. Leveraging CWDM technology, they enable simultaneous transmission of multiple optical signals across different wavelengths over a single optical fibre. This enhances the fibre’s capacity, allowing for swift data transfer. Additionally, these transceivers offer a transmission distance ranging from 20km to 80km, making them suitable for various network configurations and requirements.

Figure 1: FS 10G CWDM SFP+ Transceiver

10G DWDM SFP+ Transceiver

The 10G DWDM SFP+ transceiver plays a crucial role in fibre optic networks, utilizing DWDM technology. This innovative approach allows multiple optical signals to travel concurrently down a single optical fibre, each with its own distinct wavelength. Consequently, significant amounts of data can be transmitted efficiently over a single fibre. Moreover, these transceivers support transmission distances of up to 80km, ensuring their suitability for a wide range of network configurations and requirements.

Figure 2: FS 10G DWDM SFP+ Transceiver

Differences Between 10G CWDM SFP+ and 10G DWDM SFP+

Wavelength Range

CWDM SFP+ transceivers typically operate within the wavelength range of 1270 to 1610 nanometers, whereas DWDM SFP+ transceivers operate within a narrower range, typically between 1525 to 1565 nanometers. CWDM systems utilise a broader wavelength range, allowing them to transmit fewer optical signals. This helps reduce signal interference in the optical fibre, leading to improved spectrum utilisation. On the other hand, DWDM systems transmit more optical signals within a narrower wavelength range, enabling higher channel density.

Channel Count

Due to the differences in wavelength spacing, CWDM systems typically support fewer channels (usually between 8 to 18 channels), while DWDM systems can support a higher number of channels (typically between 40 to 80 channels). Choosing the right transceiver can be adapted to actual needs, thus providing a more flexible network configuration.

Power Consumption

The power consumption of CWDM systems is significantly lower compared to DWDM. In DWDM systems, the cooler and control circuitry used in the laser consumes about 4W per wavelength, whereas CWDM lasers, which do not require a cooler, consume only around 0.5W. For instance, a 4-wavelength CWDM optical transmission system typically consumes about 10-15W, while a similar DWDM system can consume up to 30W. As the total number of multiplexed wavelengths and single-channel transmission speed increases in DWDM systems, managing power consumption and temperature becomes critical in circuit board design.


10G SFP+ CWDM is ideal for shorter-distance data transmissions and scenarios where there’s a lower need for multiple channels. This includes applications like campus networks, data centres, FTTH (fibre to the Home), as well as 1G and 2G fibre channels, and 10 Gigabit Ethernet setups in metropolitan area networks (MANs), alongside security and surveillance systems.10G SFP+ DWDM is better suited for long-distance data transfers and scenarios requiring higher channel density, such as inter-city or international long-haul data transmissions and interconnecting data centres. Additionally, DWDM systems offer compatibility with future all-optical networks, ensuring robust and reliable networking solutions.

Tips on Choosing the Right 10G CWDM/DWDM SFP+ Transceiver

When you’re planning or expanding a fibre optics network, there are many things to consider. The networks grow in complication very quickly, and any miscalculation can prove expensive, if not serious. The following tips are important factors to consider when choosing the right 10G CWDM/DWDM SFP+ transceiver.


CWDM technology is commonly used to boost fibre network capacity, especially when maximising spectral efficiency and achieving long-distance coverage aren’t top priorities. For such scenarios, opting for FS 10G CWDM SFP+ Transceivers is ideal. However, if you need higher speeds, greater channel capacity, or applications that require amplifiers for data transmission over longer distances, FS 10G DWDM SFP+ Transceivers would be a suitable choice.

fibre Optic Types

G.652 and G.655 fibres are both suitable for DWDM systems, particularly when transmitting data at speeds exceeding 10Gbit/s. However, to ensure optimal system performance, it is recommended to use G.655 fibre in DWDM configurations. Additionally, when the DWDM system operates on the L-wavelength, G.653 fibre can also be used. In the case of an 8-wavelength CWDM system, where specific fibre requirements are not defined, G.652, G.653, and G.655 fibres are all viable options.


There is a difference in cost-effectiveness between CWDM and DWDM systems. Due to their wider wavelength spacing and fewer channels, CWDM systems typically have a lower cost. In situations where budgets are limited or there isn’t a high demand for communication bandwidth, CWDM systems may be the more cost-effective choice.


In summary, 10G CWDM/DWDM SFP+ transceivers play a crucial role in modern networks, facilitating high-speed fibre optic data transmission. CWDM is suitable for prioritising spectral efficiency and short-distance transmission, while DWDM is ideal for long-distance and high-density channel requirements. When choosing, factors such as transmission distance, fibre type, and cost-effectiveness should be considered. A thorough understanding of their characteristics and applications can assist you in making informed decisions.

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