The prevention of error propagation in dictionary compression with update and deletion

In earlier work we presented the k-error protocol, a technique for protecting a dynamic dictionary lossless compression method from error propagation as the result of errors on the communication channel or compressed file. Experiments showed that in practice this approach is both fast and highly effective against a noisy channel or faulty storage medium. This past work addressed dictionary-based methods where new strings are added over time. Here we address the issue of dynamically deleting strings. Although without modification most standard methods used in practice (e.g., LRU strategies) perform poorly with respect to error propagation, we propose and analyze some that are very robust, including a strategy based on leaf pruning