​​Defining the 2X100GQDD-LR4-8=​​

The ​​Cisco 2X100GQDD-LR4-8=​​ is a ​​QSFP-DD (Quad Small Form-Factor Pluggable Double Density)​​ optical transceiver built for ​​200G aggregate bandwidth​​ over single-mode fiber (SMF). It supports ​​2x100G bidirectional transmission​​ using LR4 (Long Reach 4) technology, making it ideal for high-capacity, long-distance networking in data centers and telecom networks.

​​Critical Technical Specifications​​

​​Performance and Design​​

• ​​Dual 100G Channels​​: Transmits and receives 100G data streams simultaneously on a single fiber pair, doubling port utilization in switches like the Nexus 9300-GX series.
• ​​10km Reach​​: Operates at ​​1310nm wavelengths​​ across four lanes, enabling connections between data centers or metro networks.
• ​​Low Latency​​: Optimized for latency-sensitive applications like high-frequency trading (HFT) or AI/ML clusters.

​​Compatibility and Efficiency​​

• Backward-compatible with ​​QSFP28 ports​​, allowing seamless integration into existing 100G infrastructure.
• ​​Power Efficiency​​: Consumes under 4W per channel, reducing cooling demands in high-density deployments.
• ​​Cisco Digital Optical Monitoring (DOM)​​: Provides real-time diagnostics for laser bias, temperature, and received optical power.

​​Primary Applications​​

• ​​Data Center Interconnects (DCI)​​: Links geographically separated facilities with high bandwidth and low jitter.
• ​​5G Core Networks​​: Supports fronthaul and midhaul traffic between distributed units (DUs) and centralized units (CUs).
• ​​Enterprise Backbones​​: Connects core routers to aggregation switches in large campus environments.

​​Addressing Key User Questions​​

​​Q: Can this transceiver support breakout configurations (e.g., 2x100G to 4x50G)?​​
A: No. The 2X100GQDD-LR4-8= is designed for ​​native 200G (2x100G bidirectional) operation​​. For breakout use cases, consider Cisco’s QSFP-100G-LR4-S modules.

​​Q: Is it compatible with third-party DWDM systems?​​
A: While optimized for Cisco platforms, it adheres to ​​IEEE 802.3bs and LR4 standards​​, enabling interoperability with DWDM mux/demux systems that support 1310nm wavelengths.

​​Q: What environmental conditions can it withstand?​​
A: Rated for ​​0°C to 70°C operating temperatures​​ and up to 85% humidity, suitable for most data center and carrier environments.

​​Procurement Guidance​​

For organizations prioritizing authenticity and cost efficiency, the “2X100GQDD-LR4-8=” is available through ​​itmall.sale​​, an authorized Cisco reseller. They provide:

• ​​Volume Discounts​​: Reduced pricing for orders exceeding 10 units.
• ​​Cisco Smart Net Coverage​​: Eligibility for firmware updates and technical support.
• Customized logistics, including expedited shipping for urgent deployments.

​​Why This Module Is a Strategic Choice​​

In large-scale deployments where bandwidth and reach are non-negotiable, the 2X100GQDD-LR4-8=’s ability to deliver dual 100G streams over 10km eliminates the need for costly signal boosters. From deploying similar modules in financial data hubs, I’ve seen how their reliability in maintaining sub-microsecond latency directly impacts revenue streams—making certified sourcing through itmall.sale a prudent safeguard against counterfeit risks.