1- Limit connections so only one device (browser ) can view cam stream .
This one is more tricky than it might seem. Browsers can make multiple connections. You can close old connections when there is a new connection (Server_NewConnection) however you will probably encounter cases where the wrong connection is closed.
2. This line in Client.Astream_NewData reads the http request and makes sure that the client tries to connect to the root.
'filter out favicon calls
If line.Trim <> "GET / HTTP/1.1" Then
You can change it to:
if line.Trim <> "GET /SecretPath HTTP/1.1" Then
Now you will need to enter the following URL in order to connect: http://<ip>/SecretPath