
Scaling Issues 195
The problem is that if the interval is too long, information is lost in the average. However, as
the interval gets smaller, it becomes more binary, which is also difficult to interpret.
Specifically, looking at a link over a 24-hour interval clearly highlights the problem. A link that
is full for the entire eight-hour business day, but otherwise unutilized, would show up as 33%
utilization. No hard-and-fast rule exists for selecting intervals.
Figure 8-7 Scalability of Balloons and Home Agents
A busy-hour profile for one or more classes of users needs to encompass all four factors, as
discussed in the sections that follow. You can ...