We are looking to install an Iridium / Inmarsat satellite link to the WAN port of our Transit Cat 18 for ocean passages. The link is slow at 100 kbps and expensive at $10/MB.
I would like to only allow whatsapp traffic through this link. The only way to filter and enforce outbound WAN by application is to send the traffic through Speedfusion Cloud (which we subscribe to). I understand that a few packets of data gets transmitted to Speedfusion servers before filtering takes place. Can anybody quantify how much data this is before unintended traffic is dropped?
Another way would be to enforce by protocol/port and destination IP. However, I understand Whatsapp uses quite standard ports and the IPs are always changing. Has anybody managed to workout a ruleset that only allows Whatsapp data?
Thanks in advance