INTERNET TEST SET (1996 Version)
Testing Image Transfer
When the calibarated image starts to appear for the first time, measure the seconds it takes to display. The calibrated Image scale shows the number of Bytes displayed. If the image appears slowly time seconds between scale points. To STOP your Browser Loading PRESS ESC (Netscape & Explorer).
(Important: If testing a second time your Browser Cache may store this page giving false transfer results, which may give a useful indication of the time taken to display the calibrated image already in your computer. You can use RELOAD (View menu Netscape) or clear or switch off the Cache to test transfer again.)
Work out image transfer as follows: bytes divided by seconds, eg: 20000 bytes / 10 secs = 2000 Bytes per sec
See below GETTING HIGHER PERFORMANCE
|
|
Calibrated image:
 | 4000 |
| 8000 |
| 12000 |
| 16000 |
| 20000 |
| 24000 |
| 28000 |
| 32000 |
| 36000 |
| 40000 |
| 44000 |
| 48000 |
| 52000 |
| 56000 |
| 60000 |
| 64000 |
| 68000 |
| 72000 |
| 76000 |
| 80000 |
|
(Important: Do not confuse Bytes per second with BPS which means Bits Per Second for data connections.)
WHAT PERFORMANCE CAN YOU EXPECT ?
One Byte = 8 Bits, a modem can use as little as 3 Bits to transfer one Byte depending upon degree of compression and communication method. Yes, 28.8K modems can out perform ISDN 64K connections. Please see the following table.
| HIGHEST PERFORMANCE YOU CAN EXPECT |
| Connection |
IMAGES
(5% compression
except ISDN) |
TEXT
(60% compression
except ISDN) |
ADinDEX
average
60% Text
40% Images |
| effective bytes per second (do not confuse with BPS - Bits Per Second) |
| 14.4K modem | 1700 | 4250 | 3230 |
| 28.8K modem | 3400 | 8500 | 6460 |
| 33.6K modem | 4200 | 10500 | 7980 |
56K modem
typical | 5400 * | 13500 * | 10260 * |
56K modem
best | 7350 | 17500 | 13500 |
64K ISDN
digital | 7100 | 7100 | 7100 |
128K ISDN
digital | 14200 | 14200 | 14200 |
Note: numbers in red outperform 64K or 128K ISDN (ISDN 2)
* Based on average 56k modem performance tests on standard voice telephone lines. Achieving BEST performance is dependant upon local telephone exchange, line and connection technical issues.
|
GETTING HIGHER PERFORMANCE:
You will see from the above table that dial up modems can compress Text 60%depending upon what is being sent. A number of WWW Sites (including ADinDEX) use Compact Image Techniques so overall page data is made up of around 60% text (ADinDEX current average 1996). This means you can get much higher effective performance from such Sites, as the above table shows, close or better than ISDN speeds.
A large number of Sites do not use the same Compact Image Techniques with the result you wait much longer for pages to arrive, the available Internet capacity is more quickly used up, slowing the system down for every one else.
Click HERE for professional help speeding up a web page or site.
GETTING THE MOST FROM YOUR CONNECTION:
When you have finished testing you will find more information by clicking on the Faster Access button at the top of the Internet Test Menu.
Click HERE to return to Internet Test Menu...
NB: this page is deliberately plain to enable a more accurate Image Transfer Test.
|