DWDM Optics

DWDM optical transceivers transmit data using tightly spaced wavelengths (channels) on a single strand of single-mode fiber, allowing dozens or even hundreds of high-capacity signals to travel simultaneously over long distances.

They are a cornerstone technology for metro, long-haul, and DCI networks where fiber capacity and reach are critical.

🔑 Key Characteristics

• Wavelengths: ITU-T grid in the C-band (≈1530–1565 nm)

• Channel Spacing: 50 GHz, 100 GHz (and flex-grid for coherent optics)

• Fiber Type: Single-mode (OS2)

• Reach: 40 km to 1,000+ km (with amplification)

• Amplification: EDFA / Raman amplifiers

• Multiplexing: Used with DWDM MUX/DEMUX systems

📦 Types of DWDM Transceivers

🔹 1. Direct-Detect DWDM Transceivers

• Speeds: 1G, 10G, 25G

• Form Factors: SFP, SFP+, SFP28

• Reach: 40–80 km (up to ~100 km with amplification)

• Use cases: Metro access, enterprise DCI, legacy transport

Examples:

• 10G DWDM SFP+ (C-band)

• 25G DWDM SFP28

🔹 2. Coherent DWDM Transceivers

• Speeds: 100G, 200G, 400G, 800G

• Form Factors: QSFP28, QSFP-DD, OSFP

• Reach: 80 km to 500+ km (even 2,000 km+ in long-haul systems)

• Use cases: Metro/core networks, hyperscale DCI

Examples:

• 100G/400G ZR & ZR+

• Coherent pluggables with tunable wavelengths

🧩 Common DWDM Form Factors

Form Factor	Speed	Typical Application
SFP+ DWDM	10G	Metro & enterprise links
SFP28 DWDM	25G	5G fronthaul / metro
QSFP28 DWDM	100G	Metro & DCI
QSFP-DD / OSFP	400G / 800G	Core & hyperscale DCI

🌐 Where DWDM Optics Are Used

• Metro aggregation networks

• Long-haul backbone networks

• Data Center Interconnect (DCI)

• 5G backhaul and fronthaul

• Submarine and ultra-long-haul systems (coherent)

📈 Key Trends in DWDM Optics

• Shift from fixed wavelengths → tunable DWDM transceivers

• Rapid adoption of 400ZR / ZR+ pluggable coherent optics

• Replacement of proprietary transport shelves with open line systems

• Increased spectral efficiency using advanced modulation

• Convergence of IP + optical layers

⚖️ Advantages

• Massive fiber capacity expansion

• Long-distance transmission

• Lower cost per bit at scale

• Efficient use of existing fiber infrastructure

⚠️ Challenges

• Higher cost and power consumption (especially coherent)

• Requires precise optical planning and management

• More complex troubleshooting compared to grey optics

🔑 Summary

DWDM optical transceivers enable the highest-capacity, longest-reach fiber networks, making them essential for modern telecom backbones and data center interconnects.

GigOptics - Your Trusted Source for Optics

At GigOptics, we offer a wide range of DWDM optical transceivers; all tested to ensure quality and reliability. For more information, contact us at info@gigoptics.com.