COS 440

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COS 440 Computer Networks An introduction to
data communication and computer networks
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Course Overview - in a nutshell
This course provides a general introduction to
the fundamental concepts of computer networks
and data communications. Basically it describes
the different organizations in terms of component
parts - both software (from low- to high-level)
and hardware - and explaining and justifying why
they are so organized. Finally, a number of
high-level applications, such as e-mail and the
WWW, will be described in these terms.
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Course content Major topics ? Basic elements of
communications systems ? Physical communications
options ? OSI and TCP/IP models (Protocol stacks
- layers) ? Physical layer of protocol
stack ? Data Link layer ? Network layer ?
Transport layer
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? Session and presentation layers ?
Application layer ? Wide-Area Network (WAN)
architectures ? Local-Area Network (LAN)
architectures ? Modern high-speed networks
based on ATM and Frame Relay ? Interconnection
of LANs ? Applications such as e-mail and WWW ?
Broadband/Wireless networks
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Rules and Regulations (or How Not to Upset
Me!) - Attend all classes gtgt Marks will be
deducted for class absences! gtgt Persistent
absences ? dropped from class - Late arrival -
Dont! Be on time for class gtgt Will be
treated as a class absence! - Leaving class
during lecture - Dont! gtgt Will be treated as a
class absence! - Active participation -
contribution to class discussions, ask
questions, etc. - Switch off cell phone before
class!
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Methods of Assessment - Three Practical
Assignments - based on cnet and socket
programming - must get at least 60 otherwise
you will get F grade overall! Note missing
even one assignment can seriously damage your
grade - Two Written Tests - N.B. No
makeups! - must get at least 60 otherwise
you will get F grade overall! Note doing
badly on even one test can seriously damage
your grade
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Assignments Practical work, i.e
programming - cnet - a network simulator -
need to know basic use of Unix - network
programming via sockets Grading - Work is due
at the beginning of the specified class. - Late
work will be penalized.
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Academic Honesty - All answers to assignments
and tests must be your own work. - You must not
look at or copy someone elses work, or let
someone look at or copy your work. - You may
consult with me for guidance, clarification, etc.
without penalty - Academic dishonesty will be
heavily penalized.
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Code of Ethics - Students must read and take
heed of the AUBG Code of Ethics for use of
computers at AUBG, issued by the Office of
Communications (OCC) and Computing. - Any
transgression will be heavily penalized
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Course Web pages .LRN web site for course. Web
pages will contain - copy of lecture
slides - homework assignments - previous
years tests - etc.
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Textbook Computer Networks by Andrew
Tanenbaum Available on reserve in the library.
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Summary of individual student responsibilities
Attend class regularly. Turn off cell phones
before class. Be punctual - for lectures, for
any appointments. Participate actively in
class discussions. Revise class material
regularly. Read the slides and assigned readings
from the textbooks. Try out the previous years
tests. Check and read your e-mail regularly.
At least twice a day!
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Monitor the contents of the course website
regularly for any updates.
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Keep me informed if special circumstances
arise - If you are unable to attend a
scheduled class session or meeting, report
absences to me. - In case of an illness or
emergency that will affect your attendance and/or
performance in this course, notify me as soon as
possible.
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Questions?
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"The first communication revolution of the 20th
Century gave us telephone-based
communications. The second gave us computer-based
communications, including e-mail and the
Internet. The 21st Century, though, will bring us
a knowledge-based communications
revolution. Bell Labs Aside
Knowledge-based intelligent many more ideas
from artificial intelligence will be employed to
cope with the information explosion which is
now occurring with the Internet and WWW. E.g. the
new Web - Semantic Web
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In all large corporations, there is a pervasive
fear that someone, somewhere is having fun with a
computer on company time. Networks help alleviate
that fear. John C. Dvorak
Programming today is a race between software
engineers striving to build bigger and better
idiot-proof programs, and the Universe trying to
produce bigger and better idiots. So far, the
Universe is winning. Rich Cook