TDS Check sum question

[Rainwalker]

Hello all,
I am thinking that each new Radius update will always have a new check sum. I'm i correct and if so where would i find the correct new check sum so that i can compare it to what i have ( MD 5 )? As a matter of fact same question for other DC products.

TIA

[Jooske]

Hi, they are at each product's download page!

[Rainwalker]

Hi Jooske.............. :-[ where ??? i usually go here as i will often use manual > http://tds.diamondcs.com.au/index.php?page=update

[Pilli]

Hi Rainwalker, You are correct the only Checksum on the download page is for TDS3 not the radius file, someone must have removed it as Jooske rightly said there was one ??? Stop thief! .....

[Rainwalker]

:-\\ ??? :P

[Pilli]

Rainwalker, Your in luck - sort of - check page 3 of this thread :
http://www.wilderssecurity.com/showthread.php?t=19689 ;D

[Rainwalker]

Thanks for looking Pilli but ...... but... does the checksum change with EVERY Radius update and how do i compare it to what md5 shows me :-\
:)

[Pilli]

Yes it does change with every new update, the link at least shows what today's should be.
I am sure DCS may now notice that they are missing :P I know they have been changing things around a bit, so maybe when the server moved the checksums were left in the bottom of a packing case somewhere ;)

[Jooske]

Of course! as it's size changes.
I always look if the update in TDS shows the same as Gavin's postings or on top of the forum or the TDS site.
If it differs i start looking for a solution.

[Rainwalker]

Ok thanks folks.... did not know how checksum is configured .... size.. ok :) i also check the same posting Jooske but thought the checksum check would add another layer of security.... how many checks can a checksum check if a checksum checked the checksum check ;D

[Pilli]

-{ Quote: "Of course! as it's size changes.
" }-

Not as simple as that jooske unless you were just referring to the numbers that Gavin always provides?

Rainmaker, you may wish you did not ask about how :)

Here is the explanation of how a checksums can be generated, taken from the CryptoSuite help file :)

A checksum is basically an extremely large number which represents a group of data. In its simplest form it is like referencing a larger set of data by a smaller set. If your name was Michael for instance, if someone called you Mike you would know they were referring to you even though they didn't use your full name. This is similar to how a checksum works.

Checksums come in many different sizes, ranging from 1bit to 1024bit and anything over. Obviously the larger the checksum the more unique sets of data it can reference before "collisions" occur. What is a collision? A collision occurs when the same checksum or number is generated for 2 different sets of data.



What the checksum does to generate a number given a set of data, is to go through ALL the data and while it is, do certain things. The simplest checksums simply add up each byte in the data. So if I had a 20byte piece of data where each byte contained the number 1, and I ran a simple adding checksum over it, it would give me the number 20. If I changed one of those bytes in the 20, to a 2, then the same checksum would now be 21. I would know there is a difference between the two sets of 20bytes simply by looking at the checksum. But what if in those 20 bytes, there was one 20, and nineteen 0's. It would also give me the checksum of 20, which would be a collision. Simple adding checksums are only used today when extreme speed is required, because they are very simple and produce a lot of collisions.


Cryptographic checksums like SHA/HAVAL/MD5/TIGER/etc, use advanced mathematics principles to limit the amount of collisions and hence they are used today because of their high reliability.

[Rainwalker]

Thanks again Pilli and i AM glad i asked :D and glad you took the time to explain. It was a better explanation then what i had read elsewhere on the web.......... interesting reading :)

[FanJ]

Update for 19-01-2004: +25 references (+21 primaries)
[31247 references - 11139 primaries/8922 traces/11186 variants/other]


The file <C:\...\Radius.TD3> has the following Checksum(s)
MD5 - 0F72DB4BBE8A9252E01044091C771F8A


We could post ourselves the MD5 HASH of the daily Radius-file.
But that would mean a lot of extra postings ::)


And BTW: keep in mind that sometimes (not very often !) the files advscan.dll and/or dcsmutex.dll are also changed when you let TDS-3 search for an update.

[Rainwalker]

;D Anyway my little vote is for MD5 hash daily postings of :
Radius-file
advscan.dll
dcsmutex.dll Seems like a good idea but then again sometimes ignorance is bliss.....sometimes.....i think sometimes.... then again... i'm lost ........

[DolfTraanberg]

http://tds.diamondcs.com.au/md5.txt
Dolf

[Pilli]

Hey Rainwalker, I told you they had lost, now Dolf has found it for them :)
Looks rather lonely on that page all by itself :'(

[Rainwalker]

Thanks guys and three big cheers for you Dolf......you da man ;D ;D

[Pilli]

Yeh, Thanks for pointing it out Rainwalker - Have a Karma cookie.
Oh! And another for Dolf for finding it ;D

[Rainwalker]

Too funny ;D i also just sent him a cookie to have with his milk before he hits the sack tonight ;)

[FanJ]

Karma from me too for Dolf :)

But...eh...(the old schoolmaster speaking ::) )....
shouldn't a checksum, when posted, not also mention for which file it is calculated... ::)

[Rainwalker]

Greetings FanJ no offense intended ... my guess is that Dolf considered my question at the opening of the thread :)

[DolfTraanberg]

-{ Quote: " quoting: FanJ link=board=5;threadid=19910;start=15#msg122062 date=1074629935]
But...eh...(the old schoolmaster speaking ::) )....
shouldn't a checksum, when posted, not also mention for which file it is calculated... ::)
" }-
Well, the file is located at the TDS site....
Thanks for all those cookies :D
But for me this was an easy one, because I host one of the mirrors, I asked Gavin to put that checksum there, so I could verify if I got the right Radius. ;)
Dolf