The Anatella software in-itself does not access the network.
However, some ODBC drivers (for example: the MySQL ODBC drivers) and some OleDB drivers are accessing their database through a network connection. For these reasons, you should configure your firewall to allow Anatella to access your network (or at least, to allow access to the required database).
There are also some specific Anatella Actions that are accessing the network when used (This is a normal and expected behavior): Such Actions are:
Query SMS Delivery Status, 
Geocoding & Reverse Geocoding, 
TCP-IP Receive table, 
Get Email, 
InfoOnIp, 
Send Email, 
TCP-IP Send table, 
Send SMS HTTP, 
Send SMS SMPP, Hadoop HDFS storage.
Anatella also uses cURL to run the following actions: These actions are accessing different Cloud services using the cURL:
The 
DownloadAndUpload action (see section 5.23.1), The 
Multiple DownloadAndUpload action (see section 5.23.2), The 
generic REST API call action (see section 5.23.3), The 
VAT check action (see section 5.23.4), The 
Tableau Publish action (see section 5.23.5), The 
S3ListFilesInBucket action (see section 5.23.6), The 
S3DownloadFile action (see section 5.23.8), The 
S3UploadFile action (see section 5.23.9), 
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