15.566
Information Technology as an Integrating
Force in Manufacturing
Session 7 of 25
MASSACHUSETTS INSTITUTE OF TECHNOLOGY
Sloan School of Management
Prof. Brian Subirana
(*) Some of the transparencies used in these sessions are based on slides used by the IT group in previous years
Why build networks?
QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this p
A
B
QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this p
QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this p
C
D
QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this p
Full Connectivity doesn't scale!
Prof. Brian Subirana, MIT Sloan School of Management and IESE Business School -University of Navarra
SM
Networks are about sharing
Network
• The network allows an entity to switch its attention among a
large number of others
• Permits sharing of resources attached to the network,
including the resources of the network itself.
Prof. Brian Subirana, MIT Sloan School of Management and IESE Business School -University of Navarra
SM
Two forms of network connection
• Circuit or line switching
– A dedicated end-to-end connection is established for the
duration of the connection
– Used in telephone network
• Packet switching
–
–
–
–
–
Messages are divided into small packets
Each packet is separately routed to the destination
Different packets can take different paths and times
Missing or garbled packets are retransmitted, if necessary
Packets are reassembled into messages at the destination
Prof. Brian Subirana, MIT Sloan School of Management and IESE Business School -University of Navarra
Line switching
Local call
QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this p
QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this p
Limited capacity
between switches
QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this p
SWITCH
QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this p
SWITCH
QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this p
QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this p
QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this p
QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this p
QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this p
Limited
switching
capacity
Established phone
call: dedicated line
Limited
switching
capacity
Prof. Brian Subirana, MIT Sloan School of Management and IESE Business School -University of Navarra
QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this p
Packet Switching
2
4 3
1
QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this p
Host
Router
QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this p
Host
QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this p
Router
Communication
lines
Router
QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this p
QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this p
Router
Host
Router
Prof. Brian Subirana, MIT Sloan School of Management and IESE Business School -University of Navarra
Host
Packet Switching
4
3
1
QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this p
Host
Router
QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this p
Host
QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this p
Communication
lines
Router
Router
QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this p
QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this p
Host
Router
Router
Prof. Brian Subirana, MIT Sloan School of Management and IESE Business School -University of Navarra
Host
2
Comparison
Circuit switching
Packet switching
Minimum delay
Variable delay
Very inefficient use of
connection capacity
Much more efficient use of
connection capacity
When overloaded, unable
to make connection at all
Can almost always connect,
but may be long delays
Both ends of connection
must use same data rate
Data-rate conversion is easy
Prof. Brian Subirana, MIT Sloan School of Management and IESE Business School -University of Navarra