The U.S. Department of State – BT Federal helps mitigate risk

The U.S. Department of State’s Microsoft Exchange environment consists of 300 Exchange sites worldwide, servicing over 40,000 users. As the Exchange environment became operational and usage grew, DoS experienced severe impacts to performance. Administrators noted that the message-based directory replication within Microsoft Exchange was heavily contributing to the message traffic. Of the 120,000 messages traversing the backbone servers, 80,000 of these messages were in support of the Microsoft Exchange directory replication processes. This situation was further aggravated each time one of the local site administrators initiated a replication of a directory.

The DoS experienced two major and costly outages to the entire enterprise. A local site administrator testing changes to their local Microsoft Exchange directory, inadvertently caused numerous directory replication messages to flood the network.

BT Federal proposed to replace the Exchange directory replication with its directory technology, including synchronization services to each of the 300 Exchange sites. Not only did the solution solve the replication problem; it also accommodated the logistics of phasing the implementation at the local sites.

BT Federal designed a highly available directory infrastructure consisting of six directory backbone servers. The backbone servers replicate changes among themselves allowing the local site a single interface to one of the six backbone servers. Once a day, each local site initiates an automated replication request to the backbone server during non-business hours. This design implements DoS standards and policies via the synchronization scripts and provides highly reliable, consistent and up-to-date local address lists worldwide.