Datagram Transport Layer Security (DTLS ) is a protocol used to secure datagram-based communications. It's based on the stream-focused Transport Layer Security (TLS ), providing a similar level of security. As a datagram protocol, DTLS doesn't guarantee the order of message delivery, or even that messages will be delivered at all. However, DTLS gains the benefits of datagram protocols, too; in particular, the lower overhead and reduced latency.