Technical guides

• What a 'Coded' SFP Module Is, and Why Switches Accept It

  An explanation of how EEPROM coding on SFP/SFP+ modules works, why Cisco, Huawei and H3C switches see them as supported modules, and the limits worth knowing about

  Updated 2026-09-06

• How to Choose the Right 10G SFP+ Module: SR, LR, ER or a DAC Cable

  A comparison of 10GBASE-SR/LR/ER modules and DAC cables for 10-gigabit links, with the real distances on OM3/OM4 fiber and the mistakes people make most often when they pick the wrong type

  Updated 2026-09-03

• Replacing a UPS Battery Yourself: Signs of Wear, Service Life and the Hot-Swap Procedure

  How to spot a worn UPS battery, the real service life at Thai temperatures, how to find the RBC code from an APC model, and the steps for swapping the battery yourself, hot and safely

  Updated 2026-08-28