{"id":19485,"date":"2026-06-03T06:19:11","date_gmt":"2026-06-03T06:19:11","guid":{"rendered":"https:\/\/www.fibermall.com\/blog\/?p=19485"},"modified":"2026-06-18T03:42:45","modified_gmt":"2026-06-18T03:42:45","slug":"qsfp56-module-types-sr4-dr4-fr4-lr4-er4-selection-guide-2026","status":"publish","type":"post","link":"https:\/\/www.fibermall.com\/blog\/qsfp56-module-types-sr4-dr4-fr4-lr4-er4-guide.htm","title":{"rendered":"QSFP56 Module Types: SR4, DR4, FR4, LR4 & ER4 Selection Guide (2026)"},"content":{"rendered":"\n

The wrong QSFP56 module costs more than the part. It costs a fiber plant rebuild.<\/p>\n\n\n\n

We’ve seen it happen. A data center in Texas ordered 80 QSFP56 SR4 modules <\/a>for inter-rack links. The fiber runs measured 120 meters. SR4 tops out at 100 meters on OM4.<\/p>\n\n\n\n

The team faced a choice: re-cable the whole floor with OM5 at $8,000 in materials and labor, or swap every module to DR4. Either way, the “savings” of picking the cheapest module evaporated.<\/p>\n\n\n\n

That mistake is exactly why this guide exists.<\/p>\n\n\n\n

Most articles list QSFP56 module types with a spec table and call it done. They don’t tell you which module fits which distance. They don’t cover which fiber type you actually need. They skip how much power each one burns in a fully loaded switch.<\/p>\n\n\n\n

This guide covers all five QSFP56 variants \u2014 SR4, DR4, FR4, LR4, and ER4 \u2014 with per-module power data, a selection decision tree, and real deployment scenarios. You’ll know exactly which module to order before you touch a fiber cable.<\/p>\n\n\n\n

\"QSFP56<\/figure>\n\n\n\n
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