Encryption in transit protects data while it’s moving between the user’s browser (or mobile app) and the server. The standard protocol is TLS (Transport Layer Security), the successor to SSL. Modern portals must use TLS 1.2 minimum; TLS 1.3 is preferred.
A portal claiming security should redirect all HTTP traffic to HTTPS, enable HSTS headers, use modern cipher suites, and score at least an A on tools like SSL Labs’ SSL Server Test. Without encryption in transit, every credential, message, and document moving through the portal is potentially readable by anyone on the network path.
See our secure client portal article for full encryption patterns.