Re: TI-H: Networking


[Prev][Next][Index][Thread]

Re: TI-H: Networking




>From: Grant Stockly <gussie@alaska.net>
>>SHIVANJJS@aol.com (SHIVANJJS@aol.com) wrote:
>>
>>>i thought it was possible, don't large companys alow their employees 
to dial
>>>up to their networks with modems to connect to company resources
>>
>>Yes, they do.  But they have digital lines that can support many
>>connections through the same phone number.  It works like how you dial
>>into an ISP.

Not always, you can do the same thing with standard analog lines.

>its a phone switching station.  Any house can have 50 phones on the 
same
>line.

if the owner can pay for it. :)

>Digital lines go into it (I think about 68) and you get analogue phone
>lines on the other side.

Around here (texas) its called DigiLine, a form of ISDN PRI, 23
digital bearer (B) channels, plus two signaling (D) channels.
You can run it directly into a PM3 with up to 48 digital "modems"
and bypass the final D->A conversion (helps to reach that magical
56k line speed).

>Usually you have analogue signals installed to your house, your line 
goes
>to the phone utility, then your call is translated to digital signals,
>routed, then changed back into analogue.

Yep.  Usually the analog line from your house is routed to a
substation with a few miles of your house, where it may or may
not be converted to digital before being placed on a trunk.
Most calls go through at least 4 A<->D conversions before reaching
their destinations.  Many go through as many as 12.  The more
A-D conversions a call goes through, the less likely it is that
you will be able to reach high connection rates (56k is not
possable where I live, too many conversions, best is around 34k).

DK

______________________________________________________
Get Your Private, Free Email at http://www.hotmail.com