A protocol solution for replication of information in a NATO tactical directory

Abstract

This document describes a tactical X.500 (ref. (24)) or ACP 133 (ref. (25)) Directory protocol solution, which may be used for replication of data between NATO Directory systems over links/networks with reduced throughput capacity (lower than 20 Kbps). The benefits of replication come from improved performance during retrieval, since copies of data can be located nearer to the end user. However Directories often need to be updated in order to reflect the changes in the stored information. This also applies to Directories used in tactical environments where the communications systems often have low throughput. Since we are focusing on tactical systems with reduced data-rate and which are not built for interactive traffic, we are only discussing the protocol DISP for replicating information between DSAs. Our assumption is that each tactical unit has its own DSA. We also assume that most of the Directory information of the tactical user is downloaded upfront, using higher bandwidth communication systems, CDs or other means, and that all the traffic sent over the low data-rate tactical connections are updates or “incremental refresh” only. The protocol solution proposed in this report is based on the authors protocol proposal for tactical MMHS, which is described in the NATO STANAG 4406 Ed. 1 Annex E (ref. (1)).