noun
message-submission abstract-operation
A technical term used in computing, likely from OSI or similar protocol specifications, referring to an abstract operation for submitting a message.
このプロトコルでは、メッセージ発信抽象操作が定義されている。
In this protocol, a message-submission abstract-operation is defined.
A compound of メッセージ (message), 発信 (transmission), 抽象 (abstract), and 操作 (operation), likely a direct calque from English technical terminology.