datagram confidentiality service

A data confidentiality service that preserves the confidentiality of data in a single, independent, packet; i.e., the service applies to datagrams one-at-a-time. Example: ESP. (See: data confidentiality.)

Usage: When a protocol is said to provide data confidentiality service, this is usually understood to mean that only the SDU is protected in each packet. IDOCs that use the term to mean that the entire PDU is protected should include a highlighted definition.

Tutorial: This basic form of network confidentiality service suffices for protecting the data in a stream of packets in both connectionless and connection-oriented protocols. Except perhaps for traffic flow confidentiality, nothing further is needed to protect the confidentiality of data carried by a packet stream. The OSIRM distinguishes between connection confidentiality and connectionless confidentiality. The IPS need not make that distinction, because those services are just instances of the same service (i.e., datagram confidentiality) being offered in two different protocol contexts. (For data integrity service, however, additional effort is needed to protect a stream, and the IPS does need to distinguish between "datagram integrity service" and "stream integrity service".)