If you mean a tool that can record traffic from every device in your network then it requires some fairly complicated server like paid tool but if you just want the total of bandwidth used by all devices in a network then all you need is a router with SNMP but most consumer level routers lack it so you will have to go with 3rd party firmware like DD-WRT or OpenWrt or buy some older wired router(I remember my old tplink TD-8840T having this feature) having this feature.Is there a tool which can monitor bandwidth traffic from every device? This tp link has an app called Tether in which one can connect to their personal router via cloud and access the devices connect but it isn’t recording traffic.