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Questions tagged [checksum]

A checksum or hash sum is a fixed-size datum computed from an arbitrary block of digital data for the purpose of detecting accidental errors that may have been introduced during its transmission or storage. The integrity of the data can be checked at any later time by recomputing the checksum and comparing it with the stored one.

A checksum or hash sum is a fixed-size datum computed from an arbitrary block of digital data for the purpose of detecting accidental errors that may have been introduced during its transmission or storage.

The integrity of the data can be checked at any later time by recomputing the checksum and comparing it with the stored one. This process doesn't guarentee the data hasn't been corrupted, but is a good indication.

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C# - MD5 Checksum - format error when writing to SQL Server database table

I have a C# script meant to calculate a MD5 checksum of an online article as such: using System; public class Script { public static string TransformContent(ContentTransformationArguments args) { // CONVERT CAPTURED FIELD INTO BYTE…
Stpete111
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Hash functions and polynomial division

I understand that a CRC verifies data integrity by producing a checksum, which is the result of polynomial long division. I've heard hash values referred to as hash checksums, so my question is whether hash functions use some sort of polynomial…
Jon Behnken
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Finding sum of all bytes in a buffer

I am working on something and I am required to calculate checksum with every data sent. This checksum is the Lower 2 bytes of the 4 byte sum of all the bytes Assume I have the data as: Bytebuffer buffer = Bytebuffer.allocate(128); // assume i have…
Kaleb Blue
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Calculate MD5 Checksum Efficiently

I'm using following code to get the Checksum of a file. It uses 50% of CPU during calculations. MessageDigest md = MessageDigest.getInstance("MD5"); InputStream is = new FileInputStream("C:\\Temp\\Small\\Movie.mp4"); // Size 700 MB byte [] buffer =…
Kingsley Reuben
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Unusually high rate of corrupt JSON responses from web server, causes and solutions?

I'm building a REST based web service which will serve a couple hundreds clients that will upload/request little bursts of information throughout the day and make one larger cache update (about 100-200kb) once a day. While testing the large update…
Henry Chinaski
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Can a checksum function be used as a hash function?

I had an argument with a friend of mine. He says it can be used as one, but a hash function should have a strong collision resistance, would a checksum function have it? I'm not quite sure.
Raj
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Get table checksum in Laravel 5.4

What do you use to get the checksum of a table in Laravel? Is there something already abstracted for this or you have to use raw commands?
ali
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Compare Two Files on android and php server

I am developing an application where I have to record audio files and upload on the server. There is scenario where internet could be down and file is only half uploaded. How do I compare that file with one available on the android file system so…
Paras Watts
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Performance issues while creating file checksums

I am writing a console application which iterates through a binary tree and searches for new or changed files based on their md5 checksums. The whole process is acceptable fast (14sec for ~70.000 files) but generating the checksums takes about 5min…
Tobi
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How to verify locally built docker images?

In this question it turned out, that I cannot use the sha256 mechanism in the FROM line in a Dockerfile to verify I am using the correct locally built non-DockerHub image in another derived image. Is there another way to verify locally built Docker…
Zelphir Kaltstahl
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How to go about ensuring that client data sent to server is not modified?

Im creating a game where players can create their own levels and publish them online, so that other players can play the levels and compete for the best score. The best score will also have its game-replay saved and uploaded, so that other players…
Tobias Kullblikk
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Ansible Syntax - Checksum deployments

I am writing a script that will allow my deployments to return a checksum for nexus artifacts deployment. Everything under the when: condition is new to the script. There are variables that aren't defined here, such as checksum, but I put a default…
J. Patwary
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Looking for a simple checksum (or hash) algorithm with no collisions for ASCII strings up to N characters

To save space in the executable, I want to compute checksums (or hashes) over ASCII string and later use a checksum to look the corresponding string. This saves space, since I don't have to fill up the executable with ASCII strings; instead only,…
Shuzheng
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Get checksum of managed PE32 file using C#

Using dumpbin on my managed PE file I can see it contains a checksum in the optional header values. I would like to be able to get that checksum so that I can store it and make sure no one is replacing PE files produced by our build machine. I am…
Max Young
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Cannot recreate CheckSum result provided by client

I have a client that gave me the following test datastring: AAA|E0071001|D|20090401010101|EC|UKDC|BP|********|1|TR01| CPD|AAA123|Test Participant A123|P|BBB456|New Participant B456|P| ER2|NAHNAH1|Test Participant|20090401|| EAD|7||| …
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