On my laptop (Compaq Presario 1625 w/Win98), I use a Psion Dacom Gold Card 56k+Fax PCMCIA modem card. When I dial in to AOL, I get the message, “Connection at 115200 bps”. When I dial up on my home computer (HP Pavilion w/WinME), which has a generic 56k Winmodem, and I get the message “Connecting at 45333 bps”.
How is it possible for a 56k modem to connect at this higher speed? Or am I misinterpreting the info?
This is the maximum possible that it will connect at and not what it actually connected at.
The modem you describe and the laptop config. probably do not show you what you actually connected at.
This also happened to me.
You can ‘calculate’ your speed by looking at the data speed coming in and divide by 8 to get bits per second.
How can I do this?
Um… modems and other telecom stuff are already in bits per second.
On an external modem, anyway, the 115 200 b/s is the bitrate of the link between the serial port on your computer and the modem itself. The computer’s serial-port driver reports this to the OS.
The modem itself transmits at lower rates, typically maximums of 33 600 b/s send and 53 000 b/s receive for a “56k” modem. A bad day on the phone lines–noise, whatever–will reduce these throughput rates.
Since the link back to your computer is faster, it doesn’t bottleneck the modem.
Note that I am ignoring any data-compression that the modem might be doing.
I think that a PCMCIA modem is treated as an external modem.
I believe that the original internal modems did the same thing across the connector between the motherboard and the modem card, just without a cable.
A ‘Winmodem’ is a different beast. It takes the transmit/receive functions that the original modems implemented as hardware–the buffering and parallel-to-serial enconding and decoding–and reimplements them as a software driver. This driver drives the transmit and receive lines directly. (Current computers are powerful enough to do this without loading the system too much.)
Winmodems are much simpler than ‘real’ modems, just interfaces to the phone lines really, and manufacturers love to put them in preconfigured systems because the hardware is cheap.
Winmodems annoy people who use Linux and other PC operating systems a lot, because they are often unstandardised and rather proprietary, and they only come with Windows drivers.
Anyway, since there is mo serial interface between your computer and the Winmodem, the driver reports the bit-rate that you are actualy seeing on the phone line.
[sup]I want high-speed…[/sup]
Hmmm, how can you calculate the speed.
Try (and it’s been a while since I was on W98, so forgive me if I mislead you).
You should have a program called sysmon.exe
Fire it up either by finding the file sysmon.exe and double clicking or START - RUN - SYSMON
You should be able to (I think) EDIT - ADD and then look for a Dial Up Adaptor selection.
Choose the Bytes Received / Second and add it.
This ‘should’ show you the actualy bytes coming in to your modem (pretty sure it will work for a PCMCIA card modem).
As they are BYTES per second, divide by 8 and you will get BITS per second.
This ‘should’ give you an indication at any particular time what speed you are ACTUALLY receiving data.
Remember that even though you may have connected at (say) 48K, you will not always receive data at that speed, so watching the sysmon should show you what you are actually getting.
Hmmm. I hope this makes sense and I hope it helps.
What is being reported is the established speed between computer and modem, not between modem and other modem. You can be certain your real speed is under 56K.
This is correct. But as the modems are probably using compression algorithms, the data rate between your computer and the internet can be greater than the bit rate between the two modems. How much greater depends on how compressible the data is. If the data is highly compressible then a data rate of 115200 is not unreasonable given a line speed of 56K.
To find your true connection speed click Start, Programs, Accessories, System Tools, System Moniter. If Dial Up Adaptor: Connection Speed is not displayed, click on Edit, Add Itme. From the selections, pick Dial Up Adaptor on the left and Connection Speed on the right. Back in my dial up days this is how I kept track of my connection speed.
Unless I’m mistaken, a “line speed” of 56K isn’t possible. IIRC, the li’l copper wires that run to your phone jack won’t physically carry an analog signal much faster than around 34K bps, and it’s only through compression algorithms that a “perceived” download speed of something close to 56K is possible. No phone modem that I know of will even approximate 115K bps.
I’ve seen that, too, on internal modems.
Then why would it ever say 12400 like it sometimes does for my internal one?
It is possible that AOL simply lies. 
56K modems are different in that they connect not to another similar modem but to a digital system. As only one analogue to digital conversion takes place, the resultant (“quantisation”) noise is reduced and you get a little extra speed out of the line.
The modem really does run at 56K (in one direction anyway), and you can run the same compression algorithms over the link that you could with a 33.6K modem.
They will, but it depends on the data. You may occasionally notice your browser reporting speeds greatly above 56K when you browse a large page of text. But other data, for example JPG files, will hardly compress at all.
Just to make it absolutely clear, the 115200 refers to the data rate, not the modem’s bit rate, which will not exceed 56K.
>> I’ve seen that, too, on internal modems.
I am not sure what you are implying. Internal modems have a speed to communicate with the computer, just like external modems. Look in the properties where you can set the speed.
The DUN icon in the system tray generally reports the connection speed which is the speed the two modems have handshaked (handshanken?). That is the actual speed you are getting. Saying you can get more by using compression is a bit misleading.
Sometimes the DUN icon report the speed the modem is using to communicate with the computer. That information is pretty useless.
I’ve got connection to display and here’s what I got:
Last value: 10000000 Peak value: 10000000
There’s also a graphic representation. It’s a solid bar that tops off at just under 9.7M and it’s solid all the way across the screen.
If 9.7=9,7000,000 bits per minute then that would equal 1,212,500 bytes per minute.
Again I say, whaaaaaaa?
:smack:
That should say bits per second.
Bump. Just wanna see if anyone can explain my findings without having to start a new thread.
I assume these figures are from the “System Monitor” program?
If so, did you add the correct items/graphs, i.e. “Dial-Up Adapter: Bytes Received/Second” & “Dial-Up Adapter: Bytes Transmitted/Second”?
I added all the items under “Dial-Up Adapter” to the System Monitor Program and the only graphs that had figures like yours were the “Dial-Up Adapter: Total Bytes Transmitted” & “Dial-Up Adapter: Total Bytes Received”.
Any chance you might be looking at the wrong graphs?
And, I believe that the “Dial-Up Adapter: Connection Speed” graph in the SysMon program will give you the same number that you see when you click on the DUN icon on your system tray, which on your laptop would be that mostly meaningless 115,200 connection speed reading.
Okay, I had to switch computers. Here’s what I get when I add the stuff El Gui suggests:
Connection speed: 9.5M
Bytes transmitted: 68.2K
Bytes received: 364.7K
Interpretation?
Note to self: I REALLY need to educate myself more about this stuff.
"Connection speed: 9.5M"
- I’m stumped on this one. No idea why such a high number would show. But I doubt its slowing your connection at all.
**“Bytes transmitted: 68.2K” **
- Oh oh . . . Now is this “Total Bytes transmitted: 68.2K” or “Bytes transmitted**/second**: 68.2K”?
"Bytes received: 364.7K"
- Same as above. Is this the total reading or the per second reading? From the figures, you more likely looked at the Total figures, but to get the speed, you should look at per second readings . . .
I now have the System Monitor and the SDMB viewable at the same time. When I reloaded this page, here’s what I got:
Bytes received/second: got as high as 988
Bytes transmitted/second: about the same