Sample Noaaport Statistics

The data in the table on the left is taken at five minutes intervals during one hour. The table on the right is a calculated average per second. The columns in the table on the left side represent the following quantities:

1. the total number of bytes received in each interval (in Mega bytes)
2. the total number of frames in the interval
3. the total number of products in the interval
4. the first column divided by the second column, i.e., the average size of each frame (in bytes).

Taking averages here can be a bit misleading. For example, some of the satellite images are made of more than 3000 frames, some of the frames being very small (because they are transmitted in compressed form), and some of average size. Thus while this table suggests that each product contains, on average, a few (4 or 5 ) frames, there are exceptions that deviate substantially from this pattern.

Nevertheless, to get an idea indicative of how much a noaaport system can stress the computer, the per-second average of these quantities is given in table on the right-hand side. It is important to keep in mind that, as already mentioned, some products are made of several (2-4) thousand frames, and to be able to not miss a single one imposes a significant requirement on the computer assigned to this job.