In section 6, the conditions are relaxed, and the protocol to handle token loss, processor failure and restart, and network partitioning and re-merging is presented. The protocol is described using a finite-state machine model. Data structures used, as well as pseudocode for the work performed by processors during different states of the model, are also given. Sections 7 and 8 present the recovery protocol that maintains extended virtual synchrony during recovery after a failure, and the flow control mechanism that avoids message loss due to buffer overflow. Section 9 addresses implementation and performance.
Future work is mentioned at the end of the paper.
The important works on the subject are included as references. The Digital Library is published by the Association for Computing Machinery.