Will there be any leftover optical modules

Yes, leftover optical modules are likely to be available, particularly as older models reach end-of-life or are replaced by higher-speed modules.

Reasons for Leftover Modules

End-of-Life and Upgrades: Optical modules such as the Cisco 400ZR OSFP are reaching end-of-sale and end-of-life dates, with the last order date in June 2025. After this, some units may still be available through certified refurbished programs or trade-in initiatives, but supply will be limited and on a first-come, first-served basis . Market Dynamics: As data centers and hyperscalers upgrade from 400G to 800G and 1.6T modules, older 400G modules are being phased out. These replaced modules, while still functional, may not meet the performance requirements for high-speed applications and often enter the secondary market for lower-speed or budget-constrained scenarios . Used and Refurbished Modules: Manufacturers and resellers often reintroduce slightly downgraded or used modules into the market. These modules may have minor cosmetic defects or slightly out-of-spec parameters but remain operational, providing a cost-effective option for internal monitoring, backup links, or smaller-scale deployments . Supply Chain Considerations: Market forecasts indicate that while 800G and 1.6T modules are ramping up, there may be temporary oversupply or leftover inventory if demand slows or if adoption rates vary among cloud and enterprise customers . This could result in additional availability of older modules in the short term.

Practical Implications

• For buyers: Leftover modules are most likely to be found through certified refurbished programs, secondary markets, or trade-in schemes offered by manufacturers.
• For data centers: These modules can serve as backup, testing, or low-speed interconnect solutions while newer high-speed modules are deployed.
• Timing: Availability is highest immediately after end-of-life announcements and during transitions to next-generation modules, but quantities diminish over time as inventory is absorbed or recycled. In summary, leftover optical modules will exist, particularly from older 400G lines and end-of-life products, but availability is limited and often tied to refurbished or secondary market channels .