Typical ISDN Speeds?

[malanl]

Hey,
At the risk of soliciting advice from you speed freaks-I wondered if you could give me a sanity check-I realize the forum is more geared to cable modem and other such connections-but I was curious if anyone could answer a question re. typical ISDN 2-ch speeds.
I know that the settings on my Eicon Diva T/A determines the delay time and minimum data transfer rate for initiating the 2nd line kicking in (and I have yet to change those settings). I have increased my receive bufffer size to 32K (from 5K) with the autofix from PCpitstop (read: novice-I know, I know) and I have seen considerable improvement. I still am only getting a max of about 80kbps download speed when my connection rate is supposed to be supposedly 128K with both channels-which my T/A indicates that both are active during the test. I am wondering if the limitation is through the printer port speed-as that is how I connect.

Any suggestions or forehead slapping responses are welcome!

Thanks,
Larry

[Gamilon]

i assume this is an internal isdn ta i had these problems
when using an internal and external modems was not solved until i purchased a isdn router unknown why this fixed the problem
but i purchased a Netgear RT338 isdn router works great also brought my ping rates down in some cases by half
and i get full bandwidth all the time....

[p2ii]

you should probably be getting between 100 and 110 Kbps with a connection like that. Try the tcp optimizer mtu test, it will tell you what your maxmtu should be set at and that may help.

[DaveM]

Originally posted by malanl
I am wondering if the limitation is through the printer port speed-as that is how I connect.

You guys seemed to miss the most important part of his post.
The ISDN Modem connects to the Parallel port on his computer ?!?

That doesn't sound ight, but could be some really old type of ISDN connection.

If so, I'd think about upgrading to an ISDN adapter that connects via USB or at least RS-232 serial port. Or maybe, even an internal ISDN card.

[JeffL]

RS-232 serial

The serial port is slower than the parallel port...RS232 or not, its slower.

An ECP type parallel port can achieve a high enough transfer rate for 128k ISDN.


In any case, using the parallel or serial ports is CPU intensive and bogs down the system as data transfer rate increases.