Integrated Services Digital Network - ISDN

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Integrated Services Digital Network - ISDN
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ISDN 1

• Uses pulse code modulation
• Analog values encoded using A-D converters
• Integrated services
• Voice
• Data
• Video

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ISDN 2

• 1 - Basic rate 128K bits/sec
• 2 - Primary rate 2M bits/sec
• Basic access rate - ISDN2
• F B1 D B2
• F frame
• B, B2 64K bps
• D Data 16 K bps
• One bearer 2 wires

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ISDN 3

• Basic rate
• Modes of operation
• 1-64K voice 1-64K Data
• 2-64K128K Data
• Modes programmable
• D channel used by Telco often
• Uses copper pair

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ISDN 4

• Primary rate access
• 30B (64K) channels (23-USA)
• 1D (64K) channel
• T1 line 2.048 Mbps
• In USA 1.544 M bps
• PABX private branch (business)
• exchange

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ISDN 5

• 128K is 1/8 of a Meg approx
• 64K is 1/16 Meg approx
• 2.048 M bps
• Available lines 30
• Connected lines 50
• Video phone uses 64K
• low resolution - 5 cm square

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ISDN 6

• Diagram of PABX
• ISDN6 6 64K 384K
• Good quality video conference
• Similar to VHS
• Video television quality 2.048M
• MPEG moving picture
• JPEG static picture

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Features 1 of ISDN

• Integrates voice, data and video
• Digital high quality digital transmission
• Improved, expanded, programmable services using
  B and D channels
• Greater efficiency several calls on same line
• Dial up service digital end to end

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Features 2 of ISDN

• Basic rate expensive in UK
• Users have not taken up ISDN because of cost in
  UK
• ISDN popular on mainland Europe, e.g. in Germany
• ISDN has defined sets of digital standards

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Features 3 of ISDN

• The facts
• ISDN equipment often does not interoperate
• ISDN equipment must be matched
• ISDN products offered in countries vary to some
  extent
• ISDN connections can be difficult to setup