Wlan interface bridge

RouterOS Beginner Basics
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  1. Do I need to bridge wlan interface for me to have a basic home setup?
  2. What’s the advantage of the default setup where eth2 and wlan1 are bridged?
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You can have anything you want. Basic home setup is to have one big LAN where all connected devices see each other, because that’s what home users usually need. But if you don’t like it, no problem, you can split it any way you want. Separate wired and wireless LAN, isolated guest LAN using virtual AP, … anything.