The .rar format is the output of an archival system that splits up large files into many smaller, compressed files. Posts in the multimedia groups usually are in this format and it is sometimes used in the MP3 groups. A shareware program called WinRAR is used to re-combine all the parts once you download them.

When you find a group of .rar files you are interested in, make sure that all the .r0* files exist before you start downloading them. You will need the .rar file and the .r00 through .rXX files to decompress the entire archive. If a RAR archive is split into more than 100 chunks, the file extension continues to .s00 through .s99 and then .t00 through .t99. Each piece of a .rar series will all be the exact same size except the .rar file itself, and the last one in the series, which will be smaller. So if you find a 15 part RAR archive, you will see a .rar, the .r00 through .r14 all being the same size, and a .r15 which will be smaller (or possibly the same size if it happened to be an even multiple of the file size but this is rare).

To combine all the pieces of a RAR archive, you need to download and install a shareware program such as WinRAR. They offer a free trial just like NewsBin does.

Use the "Find In Subject" feature to isolate the .rXX files using Regular Expressions (RegEx). This RegEx will show all the .r?? files: \.[rst][a0-9][r0-9]. In english, this means look for a "." (the "\" escapes the ".", otherwise it means "match any single character") then match an "r", "s", or "t", then match either an "a" or a digit 0 through 9, then match an "r" or a digit 0 through 9. If you are looking for a specific series like "amovie.rXX", use amovie\.r[a0-9][r0-9].

Notice that all the files are 15MB except for the .rar, which is 14.91MB and the last file in the series, .r30, which is 13.51MB. This is a complete post because all the files from .r00 through .r30 including the .rar exist.

Once you download all the .rar files, go to the "Downloaded Files" tab and double-click on the .rar file. This will automatically launch WinRAR which will combine the files for you (assuming you have installed WinRAR as we suggest above) into one big file. The resulting file can then be played with Windows MediaPlayer, RealAudio, or whatever player you have installed for the resulting file format.

Sampling downloads in RAR format.

RAR files are all those files which have ".RAR, .R01, .R02...." extensions on them. They're like ZIP files, they're files that contain other files. They require a program called "WinRAR" to decode them. We recommend using at least version 2.90 because earlier versions would ignore the "Keep Broken File" flag. The "WinRAR" program can be found at http://www.rarlab.com/.

The following steps work with WinRAR 2.90.

1) Download the ".RAR" file and double-click it in the downloaded files tab. If you have WinRAR installed, it'll get invoked. Same rules apply here as with the other sampling techniques. MPG, MPEG and MP3 and VCD.dat files are candidates for preview.

2) Click "Extract To" button.

3) Pick a download directory.

4) Click "Keep Broken Files" (this is very important).

5) Let it decode what you've downloaded. When it brings up the error window reporting missing files, just cancel out. You'll have a file waiting ready to view.

6) Download more of the file in order (r01,r02,r03...) and repeat to sample larger portions of the file.

Don't forget to rename the "vcdbla.dat" file to vcdbla.dat.mpg" to make it viewable in Mediaplayer.

NewsBin allows you to maintain multiple simultaneous connections to your news server or servers. Using the maximum of 8 connections does not necessarily mean you'll get the best datarate. There is a point of diminishing returns due to protocol overhead. With asymmetric internet connections such as Satellite, ADSL, and most cable systems, you may saturate your uplink (usually much lower datarate than your downlink) with network traffic - acknowledgments of packets. The answer is to experiment. Use one reliable server, queue up a significant number of downloads from the same group, and watch the datarate guage. Start with one connection and work your way up, 30-60 seconds at a time, watching the datarate. You most likely will see either a bell curve or a steady climb in datarate but leveling off. In our testing against a news server running on the same machine as NewsBin, we've attained datarates of 80Mbps with only 4 connections. The bottleneck for achieving high datarates will either be the quality of your internet connection, the quality of the news server, or, if you are on a 10Mbps or better internet connection, hard drive performance. Some news servers are limiting their per/connection datarates so no matter how fast your internet connection is, the best you can do can be calculated by multiplying the number of threads by the bandwidth limit.

Fine Tuning:

1) See comments under "TCP Window Size".

2) Use multiple servers: Most users find that their ISP news server is fast, but usually not the most complete. You can augment the quality of your primary news server by signing up for another news provider. By prioritizing your servers in the server window (click and drag), you can tell NewsBin to download from your primary server whenever it can and go to secondary servers as needed. This makes the most of your bandwidth because your primary server is usually the fastest.

3) Tell NewsBin about server limits: Most news servers limit the number of active connections you can have. You can tell NewsBin about these limits under the "Servers" menu. If you have hit your limit, you will see error messages in the "Status Messages" tab.

4) Use good, quality servers. Our favorites right now (changes frequently) are Easynews and Usenetserver.

See Menu > Preferences > Setup > Network Tab

To optimize use of high latency connections, NewsBin provides a setting on the "Network" tab of the "Settings" screen. A high latency connection is a connection where the download datarate is much higher than the upload datarate. The setting we provide is the "TCP Window Size". This setting configures the network connection to send more data down on the fast link for each packet acknowledgment on the slow uplink. For example, say you have a 100MB download and your TCP window size is 16K. You will be acknowledging 6250 packets with your slow uplink connection. If you crank your TCP window size up to 50K, you will only be sending 2000 acknowledgments. The tradeoff is that there is more room for bit errors in 50K than in 16K. On a clean link asymmetric link ADSL, one-way cable, and possibly Satellite on a clear day, you can take advantage of large TCP window sizes. On dialup, marginal cable modems, wireless modems, or satellite on a rainy day, you may want to keep your TCP window size smaller. Of course experimentation is the only way to truly optimize this setting.

What are CHUNK files and what should I do with them (if anything)?

When NewsBin downloads a multipart file (a file requiring more then one post to complete) it saves parts of the file as CHUNK files in the "SPOOL" directory. This directory is under the install directory. Each CHUNK file is the decoded binary of one Post. If a file is made up of 30 parts, then when the file's completely downloaded, there'll be 30 chunk files in the spool directory. NewsBin combines these chunks together to create the actual file. It knows what order to combine them in because the CHUNK file's actual extension is the index of the chunk.

What good are Chunk files?

If you lose a connection 1/2 through a download, NewsBin will use the CHUNK files to resume the download right where it left off. For example if you had downloaded 20 parts of a 40 part MPG, then your system crashed. When you restarted and re-selected the file for download, It would ignore the 20 chunks that were already downloaded and start downloading at chunk 21.

How are chunk files cleaned out?

The most common way a chunk file gets deleted is when the download finishes. In the case of terminated downloads or crashes, chunks get left behind on disk. If the chunks get more then 3 days old though, they're automatically deleted when NewsBin starts up.

Can I delete CHUNK files?

You can do whatever you want with the chunk files, delete them, move them, whatever. If you delete chunks out from under a download though the download will fail when it's time to assemble the file.

Can I save CHUNK files?

If you set "Save Chunk" mode in the advanced tab, the chunks won't get deleted. If you set "Save Chunk Text" mode, the encoded data is saved in the spool directory. If you see corrupt data errors, you could examine the text file to see if the encoded data's any good.

How can I manually assemble chunk files?

Because of the way the chunks are named, the Master Splitter assembler will combine chunks together. They don't all have to be there either. You could use "Chunk Download Mode" to download what parts (incomplete posts) you can get then. Reassemble the partial file. You activate the Master Splitter copies in the downloaded files list right click menu under "Combine Files".

There are a couple file types that can be played even when there's only a part of the file downloaded to your disk. These files are mpg, mpeg, mp3 and VCD.dat files.

VCD's are often posted with a .DAT extension. They're really MPG files so, all you have to do is rename it to "vcdbla.dat.mpg" to play it.

Most other files like AVI, ASF,ZIP and RAR files are useless if the while thing isn't on the disk (please let me know if there are other file formats the can play partial files).

With NewsBin 3.32 it was possible to preview the downloading files (those that support partial file decoding) by dragging a copy of the file out from under the downloader and playing the partial file. Because of the redesign of the download layer, this is no longer possible but, you can still sample the files.

Here's how…

Say you have a 20 meg MPG or 5 meg MP3 file you want to sample.

1) Mark it for download.

2) During download, watch the download progress bar. When the progress bar shows

[03/20] Filename size

This means 2 of 20 chunks is in the spool directory.

3) Go into the download list tab, right click and specify "Combine Files".

4) Click the browse button, go to the spool directory which's under the directory where you installed NewsBin. Pick one of the downloaded chunks.

5) Press the "Reassemble" button. It copies the chunks together.  Remove the "chunk" extension and you have a viewable file.

6) Don't like the file? Terminate it. Want to see more? Wait till more chunks download and repeat.

Yes this is kludge, but, it's what you've got until we can automate the process.