<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns="http://www.w3.org/TR/REC-html40">
<head>
<meta http-equiv=Content-Type content="text/html; charset=us-ascii">
<meta name=Generator content="Microsoft Word 11 (filtered medium)">
<!--[if !mso]>
<style>
v\:* {behavior:url(#default#VML);}
o\:* {behavior:url(#default#VML);}
w\:* {behavior:url(#default#VML);}
.shape {behavior:url(#default#VML);}
</style>
<![endif]-->
<title>Ongoing misinformation about topology</title>
<style>
<!--
/* Font Definitions */
@font-face
{font-family:Tahoma;
panose-1:2 11 6 4 3 5 4 4 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0cm;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:"Times New Roman";}
a:link, span.MsoHyperlink
{color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{color:blue;
text-decoration:underline;}
p
{mso-margin-top-alt:auto;
margin-right:0cm;
mso-margin-bottom-alt:auto;
margin-left:0cm;
font-size:12.0pt;
font-family:"Times New Roman";}
span.EmailStyle18
{mso-style-type:personal-reply;
font-family:Arial;
color:navy;}
@page Section1
{size:595.3pt 841.9pt;
margin:42.55pt 39.7pt 42.55pt 42.55pt;}
div.Section1
{page:Section1;}
-->
</style>
</head>
<body lang=EN-AU link=blue vlink=blue>
<div class=Section1>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>I agree that the books are very vague
about networks and we can complain to the authors and I assume that many have,
but it doesn’t seem to be doing much to improve what is being written
about this topic.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>We need to remember that when we are
dealing with the concept of networks, that we cover the 3 areas of topology,
protocol and type of network separately and then the relationship between them.
We then also need to cover what is commonly used in organisations today (hybrid).
Often the books will say that a star network has a central fileserver, which is
confusing the topology (star network) and the type of network (possibly client
server). We need to make sure that the kids know the difference between these 3
areas and don’t confuse them further by only having the books as
examples.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>I did not know until about 2 years ago
that token ring was named for the protocol and not for the topology (star). I
thought that it used a token passing protocol on a ring topology. These lists
are fantastic for clearing up any misconceptions that we have, as it did for
me, so keep posting and people in the know will keep answering. <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>If we get these clear in our own minds
then we won’t confuse the kids.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Cheers Don Morelli<o:p></o:p></span></font></p>
<div>
<div class=MsoNormal align=center style='text-align:center'><font size=3
face="Times New Roman"><span lang=EN-US style='font-size:12.0pt'>
<hr size=2 width="100%" align=center tabindex=-1>
</span></font></div>
<p class=MsoNormal><b><font size=2 face=Tahoma><span lang=EN-US
style='font-size:10.0pt;font-family:Tahoma;font-weight:bold'>From:</span></font></b><font
size=2 face=Tahoma><span lang=EN-US style='font-size:10.0pt;font-family:Tahoma'>
is-bounces@edulists.com.au [mailto:is-bounces@edulists.com.au] <b><span
style='font-weight:bold'>On Behalf Of </span></b>Frank Van Den Boom<br>
<b><span style='font-weight:bold'>Sent:</span></b> Wednesday, 16 August 2006
12:36 PM<br>
<b><span style='font-weight:bold'>To:</span></b> is@edulists.com.au<br>
<b><span style='font-weight:bold'>Subject:</span></b> [Year 12 Its] Ongoing
misinformation about topology</span></font><span lang=EN-US><o:p></o:p></span></p>
</div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
<p class=MsoNormal style='margin-bottom:12.0pt'><font size=3
face="Times New Roman"><span style='font-size:12.0pt'><o:p> </o:p></span></font></p>
<p><font size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>There
have been several discussions over the past couple of years concerning the poor
understanding and confusion about network topology in texts, exam questions
etc. I was looking forward to new editions of the texts in the hope that we
would finally get it right.</span></font><o:p></o:p></p>
<p><font size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>I
was going through page proofs of the Thomson/Nelson book (new edition of
Building Information Systems), and this is what it says about Star network
topology.</span></font><o:p></o:p></p>
<p><font size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>"The
most common topology is the star network. The main type of star network has a
central computer, usually a server computer, and all computers and devices are
connected directly to it. This configuration is useful when the data to be used
is required by many people and needs to be centralised so that its integrity
and security can be easily managed. The access to the network is usually
controlled by the network operating system, that is run from the central
computer.This topology operates as a client/server network. A simple star
network is a network or segment of a network that is controlled by a switch or
hub. In this case the network is operating as a peer-to-peer network as there
is no central coordinating computer. There may be various servers operating on
the computers." </span></font><o:p></o:p></p>
<p><font size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>I
won't put in the text on Bus and Ring networks other than they do focus more on
the protocol and cabling topology. I don't know what the above treatment of
star network is based on and I find it all very confusing. There are a ton of
questions I would love to ask about this paragraph. For starters - when was the
last time any of us saw/installed/used or even read about a star network where
all the devices were connected to a central computer? I won't bother with the
rest of the questions for now...</span></font><o:p></o:p></p>
<p><font size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>In
looking at the new Janson/Dawson book, at least the focus is largely on the
protocol.</span></font> <br>
<font size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>I have
not looked at any other of the new books on this topic but I am not confident
that this confusion will go away.</span></font> <o:p></o:p></p>
<p><font size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>So
are we really clear on what we are teaching about "topology" ? I'm
not. The way the protocol works? The way the cabling is arranged?</span></font><o:p></o:p></p>
<p><font size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>Do
we all realise that even 10 years ago, it was common to find a 24-port token
ring hub, which used a star cabling topology to connect its devices, which
could have connected to it a bunch of PC's functioning on a peer-to-peer basis as
well as a database server which was being used by the same PC's for a
client-server application. </span></font><o:p></o:p></p>
<p><font size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>So
often, I read about this stuff in our IPM and IS texts in a way which treats
them all as mutually exclusive options.</span></font> <o:p></o:p></p>
<p><font size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>The
classic table that all of us have seen showing a list of advantages and
disadvantages for each of these topologies in many cases is just a lot of
rubbish in my view. For example, bus topologies are cheaper to implement
because they use less cable - might be true for coax but not an old UTP/hub
installation.</span></font><o:p></o:p></p>
<p><font size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>I
just had a quick look at the VITTA Networking CD to see how it treats protocol
- more consistent in what it considers topology to be, but there are still
things there that are oversimplified. For example, "</span></font>A
disadvantage of a ring topology is that if any device is added to or removed
from the ring, the ring is broken and the segment fails until it is
reconnected." In theory that is true, but most places would have used a
token ring hub for years, in which case it is irrelevant. But we are not really
in a position to show our students this when we teach it, and it is also
meaningless in my view.<o:p></o:p></p>
<p><font size=3 face="Times New Roman"><span style='font-size:12.0pt'>I am not
a trained communications person, and only built up an understanding of some of
these things in a large network environment that I worked in a few years ago.
So there is a good chance that some of my definitions/understanding are not
quite right. But I can assure you that the IPM and IS books that I have used
for the past 5 years have done very little to clarify much of this.<o:p></o:p></span></font></p>
<p><font size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>It's
probably too late for the authors of the new texts to review this area. Is
there some other way we can build a body of content that we agree with,
understand and can teach to kids in a meaningful way on this subject?</span></font><o:p></o:p></p>
<p><font size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>Does
anybody else out there feel the same way about this as me???</span></font> <o:p></o:p></p>
<p><font size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>Frank</span></font>
<o:p></o:p></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>_______________________________________________ <br>
<a href="http://www.edulists.com.au">http://www.edulists.com.au </a>IT Systems
Mailing List kindly supported by <br>
<a href="http://www.vcaa.vic.edu.au">http://www.vcaa.vic.edu.au </a>- Victorian
Curriculum and Assessment Authority and <br>
<a href="http://www.vitta.org.au">http://www.vitta.org.au </a>- VITTA Victorian
Information Technology Teachers Association Inc<o:p></o:p></span></font></p>
</div>
<p><font face="Arial" size="2">*******************************************</p></font><p><font face="Arial" size="2"><b>Important - </b>This email and any attachments may be confidential. If received in error, please contact us and delete all copies. Before opening or using attachments check them for viruses and defects. Regardless of any loss, damage or consequence, whether caused by the negligence of the sender or not, resulting directly or indirectly from the use of any attached files our liability is limited to resupplying any affected attachments. Any representations or opinions expressed are those of the individual sender, and not necessarily those of the Department of Education & Training.</font></body>
</html>