You have posted many many questions about VIA and you should establish a simple workflow or consult your local SE if you have detailed questions. Here is how it should work:
1- User installs VIA or has VIA pre-installed on their computer
2- Users starts up VIA for the first time and is asked for a URL
3- User provides URL which points to the VIA controller which is distributing profiles: EDIT: There could be a single controller for profiles and VIA connectivity or the controller supplying profiles can be different than the controller actually terminating VIA clients.... Both are mutually exclusive.
4- The VIA controller asks for a domain username and password
5- User enters a username and password and authenticates information based on the VIA authentication profile
6- User passes authentication and VIA provides a profile to the user's client which will include the VIA servers they will authenticate to and the method a user should use to authenticate.
7- User chooses a server from the profile and connects using the method defined in the connection profile. If the VIA connection profile allows users to save credentials, the user will not be prompted for credentials subsequent times after the initial connection.
8- The server answers, and assigns the user an ip address from the pool configured on that server.
In general, that is the process. When the user launches VIA a second time, the user only goes through 7 and 8 moving forward. The user wouldn't have to go through 1-6. If you are distributing a single server using the connnection profile via DNS, that DNS a-record can be changed so that future users will connect to a different ip address using the same dns fqdn for that server.
In a simple sense, that is how it should work.