One small correction to the below explanation. Actually for 56K to
work the Telco has to deliver digital to the ISP, with only one A/D
conversion between your house and the ISP. The ISP has to have the
necessary equipment to handle the T-1 digital and the 56K (V.90)
analog on the subscriber side.

> Hugh Vandervoort wrote:
>
> > Can anyone give me the lowdown on how faster than 33.6K connections
> > work?
> > **********************************************************************
> > I've sent alot of time trying to get my V90 modem to connect at faster than
> > 28.8 and have come to the conclusion it's in the hands of the Gods.
>
> The process isn't all that mysterious really.
>
> You have a modem, your ISP has a modem, in between the two modems is the
> telephone company's network.  The quality of the connection within the
> telephone
> company's network has a direct impact on the highest speed you can use with
> your modem.
>
> At your house, the modem is connected to an analog (read that as voice grade)
> telephone connection.  At some point, the phone company will convert that
> analog signal into a digital signal (usually the main trunk line).  And
> -ideally- will convert the signal back to an analog circuit just before it
> enters your ISP's building.  With this perfect scenario, you should be able to
> achieve near 56K speeds.
>
> Unfortunately most TEL COs do not have complete digital networks, so there will
> be several conversions from A to D and from D to A along the pathway.  Each
> conversion (in either direction) decreases the quality of the signal being
> sent,  thereby forcing the modems to transmit at a slower rate.
Dale Laluk / [log in to unmask]
P.O. Box 308
Hudson's Hope, B.C. V0C 1V0
250-783-9921

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