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Assume that the total tag count on the tier-1 historian is 15,000.

The tier-1 historian receives 15,000 tags from I/O Servers of the following types and data rates:

• 12,000 4-byte analog delta tags changing every 2 seconds: (10,000 always fitting the real-time window and 2,000 falling outside of the real-time window being 50 minutes late).

• 2,800 1-byte discrete delta tags changing every 2 seconds

• 200 variable-length string delta tags of 32-character length changing every 30-seconds

The tier-2 historian stores the following:

• 6,000 tags with hourly analog summary calculations performed at the top of each hour (using 6,000 4-byte analog tags as tier-1 tags)

• Another 6,000 tags with 1-minute analog summary calculations performed at the top of each minute (using 6,000 4-byte analog tags as tier-1 tags)

• 1,500 tags replicated (as simple replication) to tier-2 (using 1,400 1-byte discrete tags and 100 variable-length string delta tags as tier-1 tags)

• Another 1,500 tags only stored on tier-1 (using 1,400 1-byte discrete tags and 100 variable-length string delta tags as tier-1 tags)