What is ISDN?

How does it relate to a modem that uses traditional telephone lines?

Thanks,

Robert Liguori

Nope its a special line,

Its in between (kinda) dial up and broadband.

Comes in 2 flavours

64k and 128k

How do you connect?

Can you use an adapter for standard phone lines?

Can you adapt for cable lines?

Do you need a special modem?

How do you get out? ( i.e. if it's in your home PC. )

I don't understand.

What are the typical usages of ISDN, and why would anyone choose it over a traditional modem, or cable modem?

Thanks,

Robert

You contact the phone company and ask them to install an ISDN line. Its just a digital phone line, normal lines are analogue. BTW it stands for Integrated Services Digital Network.
I'm not sure if the lines are physically the same, I know ISDN runs a much higher voltage
Kind of, its called a terminal adaptor though. Modems MOdulate and DEModulate the digital signal comming to/from your PC into an analogue sign suitable for your phone line(the high pitch screaching you hear on connection). As ISDN is all digital no modulation/demoduation is required, you do however need to change the signal levels/rates to what ISDN expect - this is what the terminal adaptor does.
Get your ISDN line, get an ISDN terminal adaptor, phone your ISP/another ISDN terminal adaptor.
You would use ISDN if a traditional (read analogue) modem isn't fast enough but a cable modem/DSL isn't available in your area, or suitable for you needs. AFAIK if you can have normal phone line you can have ISDN, this is not the case with DSL which has far lower limits on how far you can be from the telephone exchange; clearly a cable modem requires you to have that service in your area which many don't. ISDN is also favourable if you need 'faster than modem' access directly to a company/location that doesn't offer VPN access over the internet.

As has already been mentioned you typically hear of 64Kb and 128Kb ISDN lines, the 128Kb lines are created by using two ISDN channels at once. Each ISDN line infact holds 2 ISDN channels which can be used independently of one another. Meaning you can talk on the phone using one channel, while surfing the web at 64K using the other channel. Or, you could use both channels to get 128K but not be able to use the phone until you hang up. Just like a normal phone line you are charge by the minute. If you have suitable terminal adaptors at both ends and enough lines you could use 2 ISDN lines (4 channels) to get 256K and so on.

Make more sense now?

Cheers

Jamie...

Hi,
This site may be of some help:

http://www.ralphb.net/ISDN/

An ISDN line must be ordered from the phone company. It is superior to a telephone (analog) line because it is conditioned for digital use. This is a big advantage if you live in the country, and are a number of miles from the CO.

The modem is a sore subject. You would need to check hardware compatability lists for your distro.

Your ISP must be able to support, and set you up for an ISDN line (This from memory, which may be faulty)

Getting out is simple with a Diva T/A ISDN modem. It even detected my spids automatically. I suspect black magic. God help me if I had to actually do the configuration.

We have ISDN because we are located seven load coils from the CO. An analog (telephone line) is slow and noisy. ISDN lets us use a router, and run several home computers.

If you can get ADSL, or live very close to the CO, or can get anything better, you probably don't want to pay for ISDN. This is strictly my opinion.

Sorry, when I posted this I did not notice that a much better answer had already been posted.