High Spead Leased Lines

When installing a leased line you would have used two copper wires in the past. You would have attached two 9600Bit/s modems which you would have replaced by two 33k6Bit/s or even 56kBit/s ones. Nowardays the German telecom uses to provide new digital high speed lines connections using 64kBit/s, 128kBit/s, 256kBit/s and 2MBit/s.

Well, they are high speed connections, but you can get the same speed with your old two (or four) wire copper wires. All you have to do is attach proper modems. The following listing gives a brief overview about what certain technologies can handle.

All solutions require that you have a two- or four-wire dedicated copper connection. There must not be ANY digital multiplexer or something between both ends. You can test this by connecting two wires on one end with each other and using a battery and a bulb at the other end.

The modems act as regular modems (thus you'll need to attach a router) with serial X.21 (up to 8MBit/s) interface or as bridge (thus you'll also need a router, but a regular pc is sufficient) with ethernet interface.

Features

ADSL

Distance up to 4km.
Speed up to 6.5/1.5MBit/s (asynchron).

IDSL

Distance up to 13km.
Speed up to 128kBit/s.

SDSL

Distance up to 6.5km.
Speed up to 1MBit/s.

HDSL

Distance up to 13km.
Speed up to 2MBit/s.

Radio

Distance up to 10km, need to be visible to each other, though.
Speed up to 4Mbit/s.

Distributors

There are not many distributors as only few people/organizations are able to use this kind of technology. Be warned, each modem is expensive. Expect 1.5kDM as basis.

The favourite producer of such modems is RAD Data Systems Inc. Another one is ZyXEL, a third one is Wavelan.