ISDN - Integrated Service Digital Network An ISDN user can set up two simultaneous independent Telecom calls on the
existing pair of telephone wires. The two simultaneous calls can be of any
type - speech, data, image or video. Using an ISDN line the data transfer rate with another ISDN line on dial-up basis
is a fantastic 64 Kbps ! It can go upto 128 Kbps !! Features of ISDN  | Universality : | Various facilities in the same interface. | | Portability : | Shifting of terminal possible during call. | | Integration of Services : | Speech, facsimile or data can be transmitted through the same channels. | | Flexibility of Services& : | Disconnecting / connecting the services needed by the subscriber is possible. | | Broad band : | ISDN can provide broadband connections (more than 64 kbps) also. | | | | | | The interface between the ISDN subscriber and the network is called User Network Interface. There are two types of User Network Interface :- |
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