Hello, This may not be a question of Freeradius, but I post it here to see whether someone ran into the same issue before and found a way to fix it. We're running H3C switch, configure eap authentication, client is windows 10 and uses certificate authentication. Initially windows 10 can be online and soon after that it goes offline. By checking freeradius log, we can see that accounting Acct-Status-Type is Start and later becomes Stop. We use wireshark to capture packets of windows 10 and find that, after it's successfully online, Switch sends EAP-Request/Identity to it and expects a response. Yet windows 10 ignores it. Switch sends a 'Stop' to Freeradius when it's timeout. The whole process is listed http://www.h3c.com/en/Support/Resource_Center/Technical_Documents/Home/Switches/00-Public/Configure/Configuration_Guides/H3C_S5130S-HI[EI]_S5110V2_S3100V3-EI-6W103/08/201909/1227641_294551_0.htm [ EAP relay ] section. 11. After the client comes online, the access device periodically sends handshake requests to check whether the client is still online. By default, if two consecutive handshake attempts fail, the device logs off the client. 12. Upon receiving a handshake request, the client returns a response. If the client fails to return a response after a number of consecutive handshake attempts (two by default), the access device logs off the client. This handshake mechanism enables timely release of the network resources used by 802.1X users that have abnormally gone offline. So it's quite weird, why does Windows 10 ignore it ? Appreciated for any help. Thanks.