Why RAR compression still popular ?

[BravoV]

I mean format like 7zip and maybe others that are freely available and open too.

Are there any real advantages, I mean for today, now in 2018 ? 

Its not like we're still in 90's or after early doomsday of Y2K era ? 

[ChunkyPastaSauce]

Recovery record is a big one.

[Red Squirrel]

Always found that odd too.  Worse is when they split it up in like 200 rar files.  Why do that?  There's no logical reason to do that now that floppies are obsolete.

[helius]

Always found that odd too.  Worse is when they split it up in like 200 rar files.  Why do that?  There's no logical reason to do that now that floppies are obsolete.

If by "they" you mean pirates, they have certain "rules" and old habits are hard to break. Long after floppies were not used, they still split archives to go through Usenet.

[rdl]

At least one file sharing site uses splitting to "encourage" you to pay for their service. If you are not a paying customer files are split into chunks and you can only download a part every hour or so with reduced download speed. If you subscribe, you can get the file all in one piece with no speed restriction.

Anyone that uses 7-Zip and is concerned with privacy should be aware that it saves a history of all files opened in the Windows Registry.

[Red Squirrel]

Always found that odd too.  Worse is when they split it up in like 200 rar files.  Why do that?  There's no logical reason to do that now that floppies are obsolete.

If by "they" you mean pirates, they have certain "rules" and old habits are hard to break. Long after floppies were not used, they still split archives to go through Usenet.

I've seen this on torrents (Linux distros. ) where they are split, but it's kinda pointless to do that since it's still just one torrent.  But yeah from what I heard before it sounds like it's an old habit that just never really died.

[Kjelt]

For newsgroups some blocks get lost, and it is much faster to repair 3 files of 100MB where a few blocks are lost than one file of 10GB with the same missing blocks in it. 

[rsjsouza]

Recovery record is a big one.

I use this particular recovery feature on my sensitive backups. It somehow gives me peace of mind relying in two companies to do my backups (compression + automation).

For online, certainly breaking files into smaller chunks is a great advantage. Not everyone or every corner of the world can count on high bandwidth or reliable availability.

[TerraHertz]

RAR has a particular feature that is very useful. You can attempt to open _any_ file with the RAR utility. It does not demand that the file suffix be .RAR, nor that the rar-file header and signature number be at the start of the file. It just starts scanning the file from the beginning, looking for a rar archive.

Huge benefit! It means you can take any existing file, and append a rar archive to it. For instance to a JPG image file. So you can create a file named book.jpg, which has a picture of a book cover at the start, and then an archive containing the book contents taking up most of the file size.
An image viewer utility will open the file like an image, showing the 'cover pic' and ignoring the rest of the data.
A RAR utility will find and open the archive of the book contents, ignoring the .jpg suffix and the cover image.
Hence the term "rar-book". It's a common practice in some circles.
A few examples here: http://everist.org/archives/scans/RAR-books/

Why most _other_ compression utilities won't do this, I have no idea. It's a stupid design decision imo.
(7-Zip does.) Edit: typo corrected. Wrote ALZip when I meant 7-Zip.

This leads into the topic of "features that should be standard practice in file systems in general, but aren't." But that's for another day.

[rdl]

Interesting.

7-Zip will do it if you navigate to the file using its own file manager, then double click the file. Nothing I tried within Windows Explorer worked though. It just wanted to compress it again.

[Halcyon]

Always found that odd too.  Worse is when they split it up in like 200 rar files.  Why do that?  There's no logical reason to do that now that floppies are obsolete.

It comes in handy, for example if you're transporting files on a medium that uses a FAT32 file system (many thumb drives) that doesn't support files over 2GB. It's good to have that option, you can turn it off.

I personally use RAR for the recovery record option.

[mariush]

The splitting into lots of files was also done for easy distribution in the piracy scene ... various "groups" rush to release something and whoever publishes the "release" first wins the "race", as long as the release respects some rules. So it's often easier to upload multiple files in parallel saturating your upload bandwidth instead of uploading a single file...

It's also easier to have auto upload bots pick up newly uploaded files and automatically upload them to other ftp locations and other file servers... no need to wait until the full file is uploaded.

Piracy groups also use checksum files, files which contain checksum hashes (crc32 , md5 , sha etc) and generally these checksum files are uploaded first, and then the ftp server can calculate checksum of a file as it's being received and automatically reject the upload if the final checksum doesn't match the checksum in the checksum file.  If you have 200 x 100 MB files, it's easier to just re-upload one 100 MB file instead of a single 20 GB file.
FTP doesn't allow you to position the file pointer at 5 GB into a 20 GB file and resume writing a finite amount of bytes, overwriting a part of the previously uploaded content, so you can't overwrite  a few bytes into a big file, you can only resume upload from one one, so if a byte was corrupt at 5 GB, the uploader would have to upload 15 GB again, from 5 GB to 20 GB. 

Way in the past, cracking groups would split big applications into 720KB / 1.44 MB floppy discs before uploading them to newsgroups and/or BBS sites  , and each archive would also contain a descript.ion file or README.DIZ or FILE_ID.DIZ  or some other files with special names.  BBS software or FTP clients or file managers like Norton Commander or DOS Navigator would automatically detect these files and show the contents of these files, making it easier to analyze contents of archives or stuff, like bragging about how smart you are to crack that application ... think of those as twitter of NFO files , where nfo files are "release notes" from the piracy group.

[BravoV]

I understand the need for breaking up into pieces, but c'mon, people still using FTP ? I mean for the closed private group sharing ?

For distribution and downloading, I thought torrent (or it's many variants) now days are far more efficient and "relatively" more secured ? Talking about congesting your bandwidth & recovery, I thought manual FTP-ing multiple files even with concurrent sessions can't beat torrent ? CMIIW

From recovery, ok, I did it my self,  all my important optical discs archives are heavily PAR-ed. But only in early 90s and also early 2000's where optical discs were preferred personal archival media as the cloud thingy was not popular back then, or even decent & reliable "personal" RAID storage solution were still infancy or at least not within personal budget.

Ok, fine, for those underground or like warez scenes, that they still can't change because of habit.


What I don't understand is even in formal and legit distributions still using RAR ? How come ? 

Tons examples out there, here a popular well known name, just see the Rigol's firmwares distribution using RAR ? WTF ? 

[Yansi]

Rar popular what? No way here. All of my friends prefer 7z.  And i prefer plain zip. Rarely do I see or use a rar. (Pun intended).

[TerraHertz]

Interesting.

7-Zip will do it if you navigate to the file using its own file manager, then double click the file. Nothing I tried within Windows Explorer worked though. It just wanted to compress it again.

Oops. I meant to say 7-Zip does it. ALZip does not.
You can just right-button drag the file to 7-Zip too.

The whole MSWindows file type associations system sucks. ONE action for file type? So restrictive, and built into the Registry, so _deliberately_ not portable.

Ha, using one of my RAR-book scans as an example. Those are part of an experiment.

[Kjelt]

For distribution and downloading, I thought torrent (or it's many variants) now days are far more efficient and "relatively" more secured ?

You have to realize that with torrents the stuff you downloaded is also shared back to the net and there is some bookkeeping. So in case there is a copyright or other rights involved you then act illegally.
Now laws change so in many countries downloading contents with 3rd party rights are already considered illegal by it self, however the companies enforcing the laws can only detect ip addresses that are "sharing" the files themselves, not the ones downloading the files since this would mean they have to suspoena the newsserver company in a different country.
Anyway if you do not have those files with rights you are right it is more effective.

[BravoV]

Anyway if you do not have those files with rights you are right it is more effective.

This is what I mean, the excuses of correcting even just few bytes in the middle Giga bytes download is not a big deal with torrent that has quite nice recovery and error checking mechanism, the client simply just re-request the offending near by small pieces to correct that.

Regarding legality, don't see if anyone is using torrent means they're bad/naughty, there are lots of legit stuffs also served in torrent style, its damn efficient and reliable compared to uploading/downloading small chunks of files, and also bandwidth utilization is also really good either for uploading or downloading, the bandwidth can be easily saturated or throttled down efficiently if you want to.

[HighVoltage]

One benefit:
The .RAR encryption is very good and can only be broken trough brute force. Try that on a 20 digit odd passphrase, it will take forever. As far as I know, all the other compression utilities have weak encryption and can be cracked within seconds.
 

[BravoV]

One benefit:
The .RAR encryption is very good and can only be broken trough brute force. Try that on a 20 digit odd passphrase, it will take forever. As far as I know, all the other compression utilities have weak encryption and can be cracked within seconds.

I guess you agree with this argument, if you really ... I mean really want a good encryption, you better not to rely only at the built-in RAR encryption, am I right ? 

[Vtile]

Why not?

[HighVoltage]

WINRAR is using 128bit AES encryption and this is really a good and strong encryption for "normal" and quick protection.

Is it the best encryption you can get?
For sure not!
But nevertheless it is a good and reliable encryption.

If I want really good encryption, I use TrueCrypt.
Even better, use WINRAR and TruCrypt together and it is probably very safe

If I need the best encryption between research friends, I am using a self built
system with "one time pad" and a 1GB key.

[apis]

If I need the best encryption between research friends, I am using a self built
system with "one time pad" and a 1GB key.

Yup, that is the only truly 'safe' encryption scheme, assuming you got a good (true) random number generator for the key.

Otherwise it's a question of how much effort/resources you think your adversaries are willing/able to spend on defeating your protection.

If a script kiddie can crack something in matter of minutes it's pretty useless. If there is no officially published method for cracking the algorithm you use (like aes128) then it's probably safe unless you are afraid of an adversary with government level resources.

[coppice]

RAR is often useful when emailing files into or out of corporate accounts. RAR files are often not detected and deleted by the security system. I'm not sure why. They seem to pick up every other kind of compressed file bundle these days.

[cheeseit]

Unless you're truly skilled and have a background in cryptology you really shouldn't roll your own cryptography for anything of importance. Encryption is tough to get right without leaking information or being susceptible to a multitude of attacks beyond brute force.

[HighVoltage]

Unless you're truly skilled and have a background in cryptology you really shouldn't roll your own cryptography for anything of importance. Encryption is tough to get right without leaking information or being susceptible to a multitude of attacks beyond brute force.

Encryption to me is like a real "Fire Safe", it is only safe for a certain temperature and time but eventually it will get hot inside.

Cryptography has been only a hobby for me for many years, not a profession.
But I have tried to crack some protected RAR files with no success, as long as the passphrase is long and complicated enough. Well, if a government powered brute force is used, I have no idea how long they would need on a RAR file?

But, there is not too much encryption software that we can really trust.
Probably the last good one was PGP in the last DOS version.

Using one time pad is not that difficult.
It all comes down to a truly random key.
And if you make that key 1GB is size, people have to go through a lot of effort to get that key from you.
You just have to hide the key very well and do not exchange it over the internet.