This figure shows the replication requirements of an administrative VOB hierarchy. The figure displays the same administrative VOB hierarchy shown in figure 4. The administrative VOB hierarchy is located at a site in Boston. The \dev VOB is replicated to San Francisco. Because \dev is replicated to San Francisco, the VOBs higher than it in the hierarchy, \admin_dev and \admin, must also be replicated to San Francisco. An arrow points from \dev in Boston, BOS@\dev, to the replica of \dev in San Francisco, SFO@\dev. This arrow is annotated with the word replication to indicate that the replication operation is occurring. The replica SFO@\dev has a parent administrative VOB, SFO@\admin_dev, that was replicated from the \admin_dev VOB in Boston, BOS@\admin_dev. An arrow points to SFO@\admin_dev from BOS@\admin_dev to indicate that SFO@\admin_dev is a replica of BOS@\admin_dev. The replica SFO@\admin_dev has a parent administrative VOB, SFO@\admin, that was replicated from the \admin VOB in Boston, BOS@\admin. An arrow points to SFO@\admin from BOS@\admin to indicate that SFO@\admin is a replica of BOS@\admin. A dotted line separates the Boston and San Francisco replicas. A lightning bolt-shaped arrow is drawn from SFO@\dev to SFO@\admin_dev, and another from SFO@\admin_dev to SFO@\admin to show the administrative VOB hierarchy. End of Figure 5.