- 1950 - 1965:
"Batch" processing
- Institutes have one (or a few)
powerful and
expensive
stand-alone
main frame computer:
(The IBM 360 --- with tape drives as storage)
- A computer was very expensive
(millions of dollars !!!)
- Jobs (programs)
are processed one at a time
(batch process):
- Very few universities and corporations coulg afford to buy a computer
- Institutes have one (or a few)
powerful and
expensive
stand-alone
main frame computer:
- Further information:
- IBM main frame history page: click here
- 1965 - 1978:
time shared computing
- Computers still very expensive
(millions for a
main frame and
hundreds of thousands
for mini computers)
- The computer was
accessed by
many users
at the same time
through dumb terminals
(I have used this "classic" VT100 terminal)
- The computer
executes multiple programs
at the "same" time
using the time sharing
technique
(The time sharing technique switches programs rapidly --- take the course CS355 if you want to learn more...)
- More
universities and corporations can now afford a
mini computer !!!
- Computers still very expensive
(millions for a
main frame and
hundreds of thousands
for mini computers)
- 1978 - 1982:
personal computing
(8080 Intel chip !)
- 1978:
The first
general purpose micro-chip CPU
Intel 8080
(and later the
Motorola 6502)
made personal computers a reality !
- A personal computer
was relatively cheap
($5000 for an Apple II)
(The popular Apple II personal computer - 1980)
- IBM PC introduced in
1982:
- Computers are
more proliferate.
- People have data files that
they like to share
- Data (files) must be transferred between computers to be shared
- People have data files that
they like to share
- Initial attempt
of file sharing:
- Through copying files using floppy disks
The floppy disk through the history:
(8 inch, 5 1/4 inch and the 3 inch floppy that does not "flop")
- 1978:
The first
general purpose micro-chip CPU
Intel 8080
(and later the
Motorola 6502)
made personal computers a reality !
- 1980's - 1990's:
- Very cheap
(personal) computers
- proliferation of
workstations and
personal computers !
- Tons of people want to share files...
- There is a need to
share
information (files)
more easily
then copying to
floppy disks !!!
- Connected computers
and develop software to
allow computers to
exchange
messages !!!
- This is the start of computer networks !!!!
- Connected computers
and develop software to
allow computers to
exchange
messages !!!
- Very cheap
(personal) computers
- Aptly saying:
- Neccesity is the mother of all inventions.....
- The first computer network
was:
- the ARPA net
(Advanced Research Project Agency)
The ARPANet built around 1969.
- the ARPA net
- Motivation:
- ARPA has sponsored
a number of research centers
with large
computing centers (super-computers
Problem:
- How to let researchers at other sites gain access to these super-computers ???
- ARPA wanted to create:
- a communication network that allows remote users to use the computers at the ARPA-sponsored computing centers
(Super-computers were extremely expensive)
- ARPA has sponsored
a number of research centers
with large
computing centers (super-computers
- The initial
ARPANET consisted of
four nodes:
- UCLA (Leonard Kleinrock)
- Stanford Research Institute's Augmentation Research Center (Douglas Engelbart)
- UC Santa Barbara
- University of Utah's Computer Science Department
- Kleinrock (UCLA) and the first
Interface Message Processor
(router) at UCLA:
