Telecommunications and Networking

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Telecommunications and Networking
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Basic concepts

• Communication protocols (TCP/IP)
• Data transmission methods
• Asynchronous
• Synchronous
• Connecting
• Modem and TCU
• Hardwired and remote
• Data transmission channels (bps)
• narrow bands 5-30
• voice bands 1,000-9,600
• broad bands 100,000
• Types of communication lines
• simplex
• half-duplex
• duplex

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Networks

• Concept
• "a group of interconnected computers,
  workstations, or computer devices (such as
  printers and data storage systems).
• Network topology
• bus
• star
• ring
• Local-area networks
• bus Ethernet, carrier sense multiple access
  (CSMA)
• ring token passing method
• Distributed data processing
• "interconnects sites of one organization not only
  for communication of data and messages but also
  for the sharing of resources."

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Distributed data processing
TSS - Time Sharing Systems
MAINFRAME
CSS - Client Server Systems
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CSS architecture
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EDI Concepts

• EDI is a mechanism for electronic trading
• EDI replaces paper flow with online transactions
• EDI architecture ----gt see next slide
• EDI is for trading partners
• Implementation plan is a key factor
• Obstacles
• lack of transaction standardization
• high start-up costs
• EDI third-party suppliers
• ATT, Control Data, EDS, GE, Western Union, IBM,
  Martin Marietta Data Systems, etc.

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EDI architecture
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Basic Communications ModelStandards are needed
at all Layers
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Layering in Major Architectures
Basic Model
TCP/IP
IPX/SPX
OSI