ISDN -  Integrated Services Digital Network

    What You can do with an ISDN Connection ?

   An ISDN user can set up two simultaneous independent Telecom calls on the existing 0pair 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 !!

   With an ISDN line you can do video-conferencing with another ISDN subscriber on dial up basis.
   Two types of Video conferencing are being offered.

•    Ordinary video conferencing (128 Kb/s), operating on one ISDN line.
•    High quality video (384 Kb/s), requiring simultaneous use of three ISDN lines.

    What Equipment you need for ISDN ?

   
   a)  an ISDN Phone Set,
   b)  a PC through an ISDN data card or digital
         Modem,
   c)  Video Conferencing equipment - for
         conference over long distances.
   d)  Digital-G4 FAX - a much faster and better
         quality of FAX sending with another G4 FAX.
         How to connect an ordinary phone or FAX ?
         No problem. Connect to the NT1 through a
        Terminal Adapter ( TA ).

    BRIEF LOOKS

    ISDN Feature Phone :- It looks like a feature phone with hands-free operation, memory dialling, LCD
                                             display etc. It can display the dialed No. calling party No. for an i/c call, & short
                                             text message. It can store the calling No. in case of “no reply” for later retrieval
                                             (log-in facility). It is also used for programming of MSN, CF etc. ( discussed
                                             later ). While signaling a “Call Waiting” it can display the waiting caller’s                                              Phone No. also.

                                             It enables use of many ISDN facilities using existing Phones, Fax machines,
                                            Modem etc. The TA may have two types of connectors.

       Analog connector :- Connect ordinary phones, Modems, FAX, Answering machine, Cordless
                                             Phones etc.

       Data Port :- Any serial port of the PC can be connected to this port. Data transfer using standard
                             software packages like TELIX, XTALK or PROCOMM is possible at 64 Kbps or faster
                             speeds upto 128 kbps. Additional Modem is not required.

      ISDN PC card :-   This card is fitted in a standard PC expansion slot. Data Transfer speed
                                     supported is 64 kbps & above.  It consists of a PC with a VDU, a Video Camera
                                     and associated controller cards plus software. The system is connected to the
                                     Exch. via 1 to 3 ISDN lines (depending on the Model). The equipment establishes
                                     connection to a similar equipment on the other side by dialling. Video images of
                                     the conference participants & / or Video tape  movies as well as conversations
                                     can be sent / received. Data transfer can also be  done simultaneously. Both the
                                     transmitted & the received pictures can be viewed on  two windows on the PC
                                     Monitor.

     On one ISDN line after the NT1 you can connect a maximum of 8 Telecom gadgets using RJ45
     plug and sockets. The internal wiring in the  subscriber premises is terminated on RJ45 sockets,
     all in parallel on a 8-wire S-bus. However, only two gadgets at a time may be used on one ISDN
     connection. Video conferencing will, of course, be only one at a time.

      “PHONE PLUS” facilities on an ISDN Line :

     ISDN also supports a whole new set of additional facilities boosting the versatility of usage.