Your task in this assignment is to investigate and report on one only of the following topics in relation to Internet application-level protocols. Each of the topics has a "theory" section, where you must briefly report on the requested aspect of the protocol under investigation, and a "practical" section where you have to demonstrate the operation of the specified aspects of the given application protocol. You may, if you wish, combine your "theory" and "practical" sections -- for example, by describing in turn each of the requested aspects of the protocol and then illustrating it with an example.
Note also that additional topics might appear on this page as they are suggested to me. It could be worth checking back regularly if you don't like any of those given below.
NB: Students using MS-Windows systems might find these telnet hints useful.
telnet, or the Unix
libwww GET command to obtain a selection of
Web pages along with their HTTP response headers -- you may, in
fact, prefer to use the HTTP "HEAD" method, since the protocol
response headers will be the same, and they're what you're
mostly interested in. If you're within La Trobe, you will have
to obtain pages via the university's proxy server at port 8080.
Document the HTTP/1.1 cache-control headers
which are present in the responses for each of the pages that
you fetch. Be sure to obtain pages from a variety of sites to
ensure that you observe a range of cache-control header
types.
telnet or the Unix libwww
GET command to demonstrate the "file
download" operation -- although not from a mail server. To do
this, you will need to discover an Internet file download site
which uses the same download technology as the Web-based email
servers -- this may not be easy! Then you should be able to
isolate the URL of a downloadable file, and fetch it using one
of the aforementioned utilities. The interesting aspect of this
is, of course, to document the relevant response
headers present in the download.
Network News Transfer
Protocol (NNTP) in the usenet
"news" system. NNTP is the basis of usenet and has many
interesting features. You should restrict yourself to the
features which relate to simply reading and posting articles:
descripion of the entire usenet system's
operation is too big a task.
telnet to connect to port 119 on a
nearby news server -- within La
Trobe,news.latrobe.edu.au is available. If
you have commercial Internet access at home or work, your ISP
will probably have informed you of the name of your news server
when you signed up. It's often something like:
news.ISP-NAME.com.au -- substitute your own
ISP's name in the obvious place.. Most NNTP servers support a
"HELP" command so you can easily discover what features they
offer. Use the protocol to learn what newsgroups are carried on
the news server, to obtain a list of article headers, and to
deliver an article. If you're really keen, try using the
protocol to post an article to one of the "test" newsgroups
(eg, latrobe.test).
telnet to connect to a POP server. If
you're on a La Trobe campus, you can probably use
students.latrobe.edu.au. Exercise some of
the protocol features mentioned in the "theory" section.
telnet. Explain why you
can't fully debug an "active-mode" FTP session using
telnet alone. For maximum possible marks,
demonstrate a "passive-mode" FTP file transfer (or directory
listing) using passive mode and telnet.
You can submit your assignment in either traditional hard copy (paper)
form, or as an email attachment of MIME type
text/html sent to
cnsubmit@ironbark.bendigo.latrobe.edu.au. Your choice of
submission format will not affect the mark gained for your assignment.
Submissions must, as usual, adhere to the requirements of the La Trobe
University, Bendigo Assignment Guide.
This assignment carries 15% of your mark for Computer Networks.
Due Date:9th May, 2003 (end of week 9)
Lecturer: Phil Scott, 5444 7277, p.scott@latrobe.edu.au.
