Hi,
As per my knowledge , When we use Logon function from xtk:session, after successfully login sessionToken generated for that user with values as
<sessionInfo>
<serverInfo defaultNameSpace="cus" instanceName="demo" majNumber="6" securityTimeOut="86400" serverDate="2021-10-18 12:11:29.342Z" servicePack="0" sessionTimeOut="86400" useVault="false"/>
In this you can see couple of values auto populated with 86400 which is set in serverconfig.xml file. So that means for this user this generate sessionToken , Security token timeout is 86400 sec and Session timeout is 86400 sec.
So in short these are the parameters which help to maintain for how long sessionToken is valid for a user.
Thanks,
Kapil