Recall broadcast

In a system of recall broadcast, each message contains a set of message identifiers called its recall set. The recall set of a message identifies all previously received messages upon which the message is based. When a message is received by a process and displayed to an external user, all messages in its recall set are also displayed to the user. The authors discuss a class of recall broadcast systems where each message is broadcasted only once, and each process stores a small number of previously received messages because these messages may be recalled in future messages.<>