NZB files
can be thought of as a road map to specific files
located somewhere on your news provider's server. When a
file is posted to a Usenet, it is usually broken up into
small segments by the posting program because news
servers set limits on the size of file they will accept
(These days, there are programs intended solely for
posting large files to Usenet). Because of the limits
imposed by the news server, large files have to be
broken up into sizes that the news server will accept.
For example, a large file like a Linux ISO might be
broken into 5-MB rars and posted in over a hundred RARs,
with each RAR being broken-up by the posting program
into many, smaller, segments, usually 384 KB each,
resulting in several hundred small pieces. Individually,
these segments are useless. It would take some effort on
the part of the person downloading the ISO to find and
assemble all of the pieces back into the original file.
If a single segment were missing you would have to find
the file's name and look for it on other servers or find
someone to repost it. (that's how it used to be done).
The NZB file (with the help of the news client and in
conjunction with PAR2 <more_info>)
does all that work for you.
A short primer on XML and NZB files (you can
skip this if you don't care).
Carriage returns, linefeeds and other characters were
traditionally used to denote the
beginning/ending/content of records. This sometimes
caused different platforms to misunderstand or
misinterpret data. XML solves this by telling whatever
is reading the record the beginning and end points of
each piece of data, what it's called, and the actual
content of the data. Without XML, different platforms
would interpret the meaning of a NZB file differently.
XML is a sort of "international language". Years ago,
French used as the official diplomatic language. There
is very little ambiguity in French, so the opportunity
for misunderstandings was reduced. Just as the French
language leaves no room for ambiguity, XML leaves no
room for ambiguity either.
Think of an XML record as a textual representation of a
small database. The NZB file is an XML record which
gives the client all the information required to find
and download all the files associated with a specific
post. The NZB file contains the news server, group, file
name, individual parts, and encoding of the file as it
was posted to Usenet (along with other information). The
NZB client takes this information, connects to your
Usenet account, downloads and then assembles the file.
To understand why this works, you need to understand
what XML is and what it does. XML is a markup language,
it defines data in a very specific way. Standardizing
how data is expressed is important because different
email readers may have different ways of interpreting
instructions to download a given file. XML records tell
whatever is reading them what the beginning, ending, and
content of certain data is. This includes the group the
data was posted to, what the subject was, who posted it,
and so on. For instance, in the groups tag, the NZB file
tells the newsreader where to look for the specific post
like this:
<groups>
<group>alt.binaries.opensource-linux-os</group>
</groups>
What this is saying is that the file was posted to one
group (note just one line between the "<groups>" and
"</groups>" tags, and the (fictional) group name "alt.binaries.opensource-linux-os"
is denoted between the beginning and ending "<group>"
and "</group>" tags. All of the data in a Usenet post is
described this way.
When properly placed into an XML record, any client
which is capable of parsing XML records can read and
interpret the data inside the record, regardless of
operating system it's running on. The client will know
exactly which group to download from, what subject to
look for, and which files to pull with that subject. It
will also know how to decode the data and reassemble it
because it has a complete list of all the pieces. All
you have to do is load the file into your client and
wait for the download to complete.
Choosing a Newsreader
To use an NZB file, you will need a newsreader
capable of parsing NZB files. Newsreaders intended for
parsing NZB files and downloading the binaries differ
somewhat from traditional newsreaders like Mozilla or
Outlook Express or Agent. There are several popular
choices for NZB capable newsreaders, and the originators
of the NZB have provided a table showing which of them
support the NZB file-type, you can see that table
here: (The link will open in a new window.) Most of
these readers are not intended for posting, so you'll
have to keep your current newsreader for reading and
posting to USENET. Personally, I prefer "BNR2"
<http://www.bnr2.org>, which is easy to set up and free.
It doesn't hurt that it was written in Delphi, a
language near and dear to my heart. Holy wars have been
fought over newsreaders, so don't worry too much about
which one you choose. At their core, they all do the
same thing; follow the NZB roadmap to the Usenet-posted
files you want, and then download them to your hard
drive.
Using NZB files
In addition to an NZB-capable newsreader, you will need
some way to obtain NZB files for the stuff you want to
download. Many posters are including NZBs with their
posts, as some of the newer versions of PowerPost, by
Assert and Alain, will generate an NZB if the poster
wishes it. But if the poster didn't include an NZB you
will need to register at
www.newzbin.com
and pay a very small fee (They accept
various forms of payment). It amounts to a few
cents per day and if you download much, is well worth
while, helping also to support the source of the NZBs.
If you're really short of cash, you can apply to be an
editor on the site (they get the NZB files for free).
For now we will assume that you're going to be a paying
member (and that you have a working news account). Once
you have logged into the site and paid your membership
fee, you have to search for whatever you're looking for.
The site is very easy to use and self-explanatory. The
search will present you with a display formatted into a
table with everything that matched your search.
Sometimes the search will have a link to an NFO file, or
a link to a website, but there will always be a link to
download the NZB. Just click the link, and wait for your
NZB file to download. If you have a newsreader like
Newsbin Pro that is associated with NZBs you can simply
"open" the NZB automatically.
Otherwise you now have an NZB file saved to your hard
drive. To download your files from Usenet, you have to
load (import) the NZB file into your newsreader. In my
example I'm using BNR2, which has a simple mechanism to
import NZBs. As noted, some NZB-capable newsreaders can
be associated with NZB files. Once you have imported the
NZB file, (assuming you configured the newsreader
correctly), download can begin. Once the download has
finished, navigate over to the folder take a look at
your files. Depending on how the uploader split the
file, you'll see zips or RAR files numbered or lettered
sequentially. If you're a seasoned downloader, you'll
know what to do next. If you're new at this, you should
take a look at The WarezFAQ's excellent tutorial on
handling archived files.
That's really all there is to it! |
