Blackboard can support numerous files and file sizes. However, your students may be connecting via a modem, making it slow and tedious to download large files. With this in mind, we recommend that files should be kept small enough for users with slower connections to be able to access the files in a reasonable amount of time.
The following table shows typical download times for various file sizes at various modem speeds.
| K/sec | 100K File | 1 MB File | 5 MB File | 10 MB File | |
|---|---|---|---|---|---|
| 14.4 Modem (older modem) |
1.5 | 66 sec | 11 min | 57 min | 114 min |
| 28.8 Modem | 3 | 33 sec | 6 min | 28 min | 57 min |
| ISDN | 7 | 14 sec | 2 min | 12 min | 24 min |
| T1 (on-campus) |
150 | 1 sec | 7 sec | 34 sec | 68 sec |
One of the easiest ways to reduce the file size of your documents is to compress any images for web delivery.
There are several things you can do in the event that you cannot limit the file size, such as:
- Compress the file using tools such as WinZip (some of which are free online).
- To eliminate any frustrations, simply provide the student with information about the file, such as the length of the file, estimated download time and the file’s importance to the course.
- Divide the existing file into smaller files allowing the student to download in multiple stages. For example, a large slide presentation of 40 slides can be divided into four files of ten.
Adapted from the Instructor's Hot Tips area of Blackboard.com.
