--- description: TIP OpenWiFi 2.0 --- # Multi-PSK \(MDU Shared Key\) Multiple Pre Shared Key is a popular configuration option in Multi Dwelling Unit, dormitory or similar environment where it is costly to implement complex 802.1x security however that same level of per-client security is highly desired. A SSID when configured for multi-psk can have multiple PSK/VID mappings. Each one of them can be bound to a specific MAC or be a wildcard. ```text "ssids": [ { "name": "MDU Wi-Fi", "wifi-bands": [ "5G", "2G" ], "bss-mode": "ap", "encryption": { "proto": "psk2", "ieee80211w": "optional", "key": "OpenWifi" }, "multi-psk": [ { "key": "akey", "vlan-id": 100 }, { "key": "bkey" "vlan-id": 200 } ], "roaming": { "message-exchange": "ds", "generate-psk": true } } ] ``` {% hint style="info" %} Note: M-PSK passwords must be unique per `vlan-id` as the device will attempt to match security key to assigned virtual lan. In the above example, a password of `OpenWifi` will match the untagged interface of the SSID and unique password of `"akey"` will match client\(s\) to virtual lan 100. {% endhint %}