[SGVLUG] Linux Class

[David Lawyer]

On Sun, Jul 16, 2006 at 10:22:12PM -0700, Tom Emerson wrote:
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> David Lawyer wrote:
> > In ... the Textbook in: 14.2 Computer Networks and Internetworking it
> > reads: "When two or more computer hardware resources (computers,
> > printers, scanners, plotters, etc.) are connected, they form a computer
> > network."  This is wrong, but what it right?
> 
> Hmmm... per wikipedia at
>     http://en.wikipedia.org/wiki/Computer_networking:
> 
>      "Computer networking is the scientific and engineering discipline
> concerned with communication between computer systems. Such networks
> involves at least two computers, which can be separated by a few
> centimeters (e.g. via Bluetooth) or thousands of kilometers (e.g. via
> the Internet). Computer networking is sometimes considered a
> sub-discipline of telecommunications."

If this is correct, then the book is still wrong since the connection
of a printer to a computer would be a network per the book.

> ...at least TWO computers -- that fits the textbook definition of "TWO
> or more", so I'd say the textbook is "right".
It's not, see above.
> 
> of course, this begs the question as to whether or not the author of the
> above page on wikipedia is "correct" or not as well, but it's a wiki --
> go ahead and "correct" the page as you see fit...
> 
> > of a network has to be fuzzy.  If I connect 2 PC's together using a
> > network protocol, then it's a network in a sense, since it uses a
> > network protocol.
> 
> oh, wait, you're admitting the book is right, but still somehow
Not so.  See above.
> insisting it's wrong -- please clarify
> 
> > But I think that two devices connected together
> > point-to-point isn't a network unless the point-to-point connection
> > is part of a larger network (like PPP on the phone line to connect to
> > the internet via an ISP).  
> 
> ok, that's a clarification.  it is overly rigorous, which gives me the
> impression you are confusing The Internet (with a capitol I) with a more
> general "network" of computers. ("The Internet" proper refers to he
> world-wide interconnection of public and private networks, while the
> term "an internet" refers to the more general case of two [or more]
> disparate networks connected by some common gateway or hub; and "an
> intranet" typically refers to two or more private networks within one
> organization.)
> 
> > 
> > So what is a network?  3 or more devices connected together, not on a
> > bus, and using a network protocol of some type (including ethernet).
> > Am I right?
> 
> For more definitions, type the search term "define:network" into
> google's search box...
> 
> 
> Or, in deference to our last speaker, you could try Yahoo's community of
> people willing to give any sort of answer to any sort of question
> (limited to 110 chars, so be brief...)

I just don't think there exists anything except a fuzzy definition of
it.  It's defined, not by writings but by how people use the term.
There's a mathematical definition of a network consisting of nodes and
links.  So just 2 nodes connected by one link is a trivial network in
which solutions to network problems like shortest path, etc. are
trivial.  So is a trivial network a network?  Some might say yes,
others no, and others would say maybe yes, maybe no.

			David Lawyer