Adapting GDOI for balanced batch-LKH
Juan Hernandez-Serrano
This document presents a new algorithm method for rekeying multicast groups. It takes advantage of the mathematical properties of modular reduction in order to reduce the number of messages needed for rekeying. Moreover the technique is very suitable for batch processing. It achieves greater bandwidth reduction than other existing batch techniques. Batch processing techniques are specially suitable for benchmarks scenarios where a great amount of users can join or leave the group at once (typically single source broadcast). One of the most important items to take into account when performing batch rekeying is that key trees must be kept balanced all the time. Current methods for batch rekeying assure tree balancing by adding an additional method to usual rekeying. We propose a batch rekeying method that allows members to change their position in the key tree. This change has to be notified to single members with the updated keys. An adaptation of the GDOI protocol in order to contain this information is finally proposed.