Axiom Memory CAB-DAC15M-Q28B4-AX 100G QSFP28 to 4 SFP28 Passive DAC

Break out one 100GBASE-CR4 QSFP28 connection into four SFP28 connections for short-reach 25G link aggregation at the rack level. The 1.5 m passive direct-attach copper assembly places one QSFP28 interface at the 100G end and four SFP28 interfaces at the breakout end. 100GBASE-CR4 uses four electrical 25G lanes, allowing a single 100G port to connect to four individual SFP28 ports without separate optical transceivers and fiber jumpers. CAB-DAC15M-Q28B4-AX is QNAP-compatible and suited to installations that require a coded passive breakout cable for QNAP networking equipment. Its fixed 1.5 m length fits adjacent equipment, top-of-rack switching, storage shelves, and closely located servers where excess cable length can obstruct airflow or cable routing. Passive DAC construction keeps the signal path within the copper cable assembly rather than adding active electronics to the cable. This specific assembly differs from a straight QSFP28 DAC by changing interface density: one 100G QSFP28 connection fans out to four SFP28 connections. It also differs from optical breakout assemblies by using direct-attach copper for short equipment-to-equipment runs. Confirm that the host QSFP28 port supports 100GBASE-CR4 breakout operation and that the four destination ports accept SFP28 connections before deployment.