What is a Cheksum Utility and What are md5-hashes?

[ErichVon]

What is a Checksum?

Quote:

Originally Posted by EtherealN

Regarding downloads, find a program that can check file md5-hashes and you can check that the installers are fine without re-downloading. You'll find hashes for the files on the donwload link. No need to re-download. This one should work: http://www.fastsum.com/press/md5-hash.php

 

My first and initial reaction is: don't install into Program Files. Windows is extremely jealous of that folder. Try installing into something like C:\Games, remember to run installer as administrator, and see how that goes.

 

Hi,

 

(This topic came up in the DCS Black Shark forum, my Message #9 to this thread:

 

http://forums.eagle.ru/showthread.php?t=77444

 

I ask it again here for maybe better coverage by educated people, including EtherealN.)

 

I am totally ignorant of this subject.

 

Would you mind elaborating or enlightening me as to what a checksum is and what the program does? Do not go nuts as to too much detail, just enough basics so I may proceed with the utility.

 

http://www.fastsum.com/press/md5-hash.php

 

I cannot be the only one that has encountered this situation with the 1.0.2 Patch in English, a Russian guy speaking comments and English written subtitles.

 

If I do not run this patch in, "Run as Administrator" a whole mess of errors are reported starting up and I cannot even open the OPTIONS menu.

 

Thanks for any help.

:pilotfly:

Edited July 29, 2011 by ErichVon

[Headspace]

I will try to be as non-technical as possible.

 

A checksum is a piece of data of fixed size (usually a number for all intents and purposes) that is usually used for performing an integrity check of received data (such as a file) and is derived from that data. See the CRC as an example of this.

 

MD5 is a cryptographic hash algorithm that while similar to a checksum (and can be used for similar purposes) was designed with security in mind; in theory it should be impossible from a practical standpoint to easily generate two blocks of data (such as a pair of files) for which the same MD5 hash will be computed. So it is sort of an electronic fingerprint. MD5, like its predecessor MD4 is now considered to be insecure but it is still often used.

 

In layman's terms you can think of checksums and hashes as unique fingerprints derived to data such as files, certificates, and so forth. I hope that helps.

Edited July 29, 2011 by Headspace

[ErichVon]

I will try to be as non-technical as possible.

 

A checksum is a piece of data of fixed size (usually a number for all intents and purposes) that is usually used for performing an integrity check of received data (such as a file) and is derived from that data. See the CRC as an example of this.

 

MD5 is a cryptographic hash algorithm that while similar to a checksum (and can be used for similar purposes) was designed with security in mind; in theory it should be impossible from a practical standpoint to easily generate two blocks of data (such as a pair of files) for which the same MD5 hash will be computed. So it is sort of an electronic fingerprint. MD5, like its predecessor MD4 is now considered to be insecure but it is still often used.

 

In layman's terms you can think of checksums and hashes as unique fingerprints derived to data such as files, certificates, and so forth. I hope that helps.

 

Hi,

 

So I am assuming programmers deliberately put these items into modules of code. What do you guys use to read them to check the integrity of your work?

[Haggart]

Uhm - if I understand you question right, you're kinda misunderstanding the principle, no offense :)

 

Checksums are like a principle to check the integrity not only of code, but any available data. They work by mathematically sum up a big portion of data (from kilo- to petabytes) into a 32-character-long string, which is mostly unique to a data package. That means every file has it's own hash, and because the string is so short, you could print it beside the download link to a big file and the downloader could calculate the hash of the downloaded data package, compare the hash and doesn't have to double download the whole data package to check on data integrity.

 

Sorry if you got that part allready, don't wanna sell you dumb. I allways use SummerProperties; that's an explorer extension which displays the MD5- and other checksums in the properties-tab of a file and works also with Seven x64. Hope that helps.

Edited July 30, 2011 by Haggart