FREQUENTLY ASKED QUESTIONS

• What is a hash function?
  
  A hash function (or hash algorithm) is a way of creating a small digital "fingerprint" from any kind of data. The function chops and mixes the data to create the fingerprint, often called a hash value. The hash value is commonly represented as a short string of random-looking letters and numbers.
  
  
• What is a CRC function?
  
  A cyclic redundancy check (CRC) is a type of hash function used to produce a checksum - which is a small, fixed number of bits - against a block of data, such as a packet of network traffic or a block of a computer file. The checksum is used to detect errors after transmission or storage. A CRC is computed and appended before transmission or storage, and verified afterwards by recipient to confirm that no changes occurred on transit. CRCs are popular because they are simple to implement in binary hardware, are easy to analyze mathematically, and are particularly good at detecting common errors caused by noise in transmission channels.
  
  
• What kind of hash algorithms/CRCs is Iside capable of displaying?
  
  lside can compute almost all existing hash algorithms. Currently it supports ADLER32, CRC32, CS16/32, HAVAL128, HAVAL160, HAVAL192, HAVAL224, HAVAL256, HMAC-SHA1, MD2, MD4, MD5, RIPEMD160, SHA1, SHA256, SHA384, SHA512, TIGER, WHIRLPOOL algorithms.
  
  
• Is Iside capable of computing a single hash code for more than one file?
  
  Yes. By selecting "Multifile Hash" from the "Tools" menu, you can select any file and the compute their checksum. The hash function is calculated on the bytes of all the input files as if they were a single entity.
  
  
• What are the uses of hash functions?
  
  Basically, hash functions determine if two files are actually the same. For instance, when downloading a file from Internet, sometimes on the site we can find the hash code of that file (usually MD5). With Iside we can easily check the file against that code to be sure that we downloaded exactly that file, bit per bit. That is, the file on our computer is the same as the file on the Internet server. This kind of check is also known as "file integrity check".
  Of course, there are a lot of other uses. For instance in Configuration Management or Versioning Systems, where we want to make sure that documents or source code are not the same version.
  Finally, by computing the hash codes of a computer folder or directory we can synchronize remote directories.

• How can I discover the hash code of a file?
  
  Just drag the file over a Iside window. To do that click with the left mouse button on the file and, by keeping it clicked, drag its icon over Iside. That's it.
  
  
• Ok, I just computed the hash code of my file. Now what?
  
  Most users just copy it in the clipboard system for future uses. To do that just double-click on the hash code and right click with the mouse. Select 'Copy'. You are now able to use your hash code everywhere. You can also save it for future use.

• How can I easily determine if two files are equal?
  
  With Iside you can right click on one file, select "Iside Copy" and then right clicking on another file discover if their contents are equal by just clicking "Iside Verify". The magic happens by computing the hash codes of the two files. You can of course confront them also with Iside application, by just dragging the files in the opened Iside window.
  
  
• I want to export the MD5 codes of my CDROM (or directory, or remote folder, or else) so that the user can check its integrity. How can I do this with Iside?
  
  The most convenient way to do so is to save the md5sum list along with the other CDROM files. To do so, select "Md5Sum/Generate" in the "Tools" menu. User will be able to open it, and, by choosing "Md5sum/Verify" he can control your CDROM integrity.
  
  
• How can I compare folder contents with Iside?
  
  By starting "Iside Folders" from Iside Start menu. With this application you enter two different directories on your computer or LAN. If the number of items (files and subdirectories) in the two folders are equal, then a comparison can be launched. Iside can find differences very fast and report them in a variety of way, included HTML or RTF.
  
  
• What Iside stands for?
  
  Iside answer the question "Is it the same?" Iside = "Ee-see-dah"