When ServiceNow is not able to access the Tachyon Server (Master Stack) over the internet then you require a MID Server. In this scenario both the Tachyon Server and the MID Server are installed on the local network and able to communicate, the MID Server can then access ServiceNow on the Internet, thereby acting as a bridge between the two.
Tachyon Users and Roles
1E Core provides ServiceNow with access to Tachyon instructions in order to provide functionality to 1E ServiceNow solutions (such as 1E ITSM Connect and 1E Service Catalog Connect). 1E Core has two roles - one for 1E Core administration and another that is inherited by the 1E solutions' accounts.
The following table describes the 1E Core app roles.
Compatibility matrix for ServiceNow apps with 1E Core and Tachyon Platform