An integrated post-locking, multi-versioning, and transformation scheme for consistency maintenance in real-time group editors

Intention preservation is an important aspect of consistency maintenance in distributed group editors. In this paper, we first introduce a classification framework for various kinds of intentions, then propose LOVOT (post-LOcking, multi-Versioning and Operational Transformation), an integrated scheme for intention preservation. With this scheme, individual users' compatible intentions are preserved by operational transformation, individuals' conflicting intentions are preserved by multi-versioning, and the preservation of a syntactically and semantically consistent group intention is facilitated by post-locking. An algorithm for preserving individual users' intentions is discussed in detail. The integrated scheme is fully distributed, highly responsive, non-blocking and capable of avoiding any locking overhead.