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Calculating modem speed

By pandbm ·
Does anyone know how to translate modem speeds. I recently had a 56V.92 internal modem installed which should give me 56 Kbps download and 48 Kbps upload speed.
Modem status showed "Connect 31.5 Kbps" and when downloading the indicator showed between 2.8 Kbps and 1.2 Kbps.
Since then I included the string "AT&FX+MS=V90\G0" in the Extra String Command box. My Connection speed jumped up to 115.6 Kbps and my speed is now 3.92 Kbps average (1,754,674 bytes in 447,109 seconds), yet the log file reports "Reads: 36Kbps" and "Writes: 31.5Kbps"
Am I looking at right figures or is there a special way to calculate these speeds?

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Calculating modem speed

by TheChas In reply to Calculating modem speed

Windows sometimes gets it wrong when it calculates the modem speed.

The 31.5 to 36 kbps is likely correct.

You need to look at hardware to see what can be done to improve your speed.

Check your phone wiring first.
Any frayed or kinked phone cords?
How old and what shape is the wires in the walls?

Try disconnecting the phone-line to all phones at the junction box, and connecting your PC directly to the junction box.

If speeds increase, then you have a noisy phone, or bad wires in the house.

If speeds stay the same, the problem is either with the lines between your house and the central switch, or the central switch itself.

There are several DUN optimization software packages available.
The "Check-It" version that I got from Smiths Micro seemed to do a decent job, and gave me very reliable numbers.

You should also try other numbers for your ISP, and see what kind of speeds your neighbors get, and who they use.

My guess is that you have old wires and an older switch. Until the phone company upgrades those, you have little chance of a faster connection.


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Calculating modem speed

by Deadly Ernest In reply to Calculating modem speed

Two points to keep in mind with modems.

1. the best actual physical data transfer speed that they can get on copper telephone lines is 33.6 kbps when the lines are in good order. If there is any trouble with the lines or any of the switching systems it is going through, then the signla will degredate and the system will automatically slow down to try and counter this.

2. any reported speed faster than 33.6 kbps (ie 56K modems etc) is due to s compression program being run on the modem, this reduces the number of signals to send thus giving the appearance of a higher speed, however the compression process has a overhead which results in a performance around the 48 to 50 kbps mark in actual data transfer. Also any line problems and this drops dramatically as the system will often drop the compression to provide a higher level of data transmission quality.

What ever compression system you are using has to match that on the other end or they will both drop back to 33.6 kbps without compression.

3. the different in reading is often due to the fact that one will give you a figure of the data that you are sending and the rate that it is going out at, whilst the other will give you a performance reading that includes the operational overhead, ie the data the modem sends as part of its checking that all is well. Thus a file of say 10 MB may result in something like 11 MB of total transmission when the modem operational overhead is included.

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