Default value of the config.vmacore.soap.sessionTimeout

Hi,

On vcenter v6 I have faced with the situation when opened vcenter soap session failed after period of idleness with the soap error:

<?xml version="1.0"?>

<NotAuthenticatedFault xmlns="urn:vim25" xsi:type="NotAuthenticated">

        <object type="VirtualMachine">vm-5967</object>

</NotAuthenticatedFault>

I suppose it happens due to the expired soap session and the question is what is default timeout value for the vcenter soap session? I've found some forum threads and KB articles where 30 min interval is mentioned. But when I try to keep session untouched for more then 30 minutes it doesn't fail (from these tests timeout value seems to be more than couple of days). I tried to get this settings from vcenter via Get-AdvancedSettings cmdlet but the parameter value is not presented in the output. Meanwhile as soon as I set this settings (via vpxd.cfg) to 5 minutes using of any session that was untouched more then 5 minutes causes the NotAuthenticated error.

Could anybody please point me to the documentation where this default value is mentioned or suggest reliable way how to identify it?

Thank you