Introducing the “Welcome to Xojo” Bundle!

New to Xojo and looking for guidance? We've put together a terrific bundle to welcome you! Xojo Bundle

This bundle includes six back issues of the magazine -- all of year 21 in printed book and digital formats -- plus a one-year subscription (beginning with 22.1) so you'll be learning all about Xojo for the next year. It's the perfect way to get started programming with Xojo. And you save as much as $35 over the non-bundle price!

This offer is only available for a limited time as supplies are limited, so hurry today and order this special bundle before the offer goes away!

Article Preview

Buy Now

Issue 9.2


Hashing for Security

A first look at cryptographic hash functions

Issue: 9.2 (January/February 2011)
Author: JC Cruz
Author Bio: JC is a freelance engineering writer from North Vancouver, British Columbia. He frequently contributes articles to MacTech and REALbasic Developer. He also wrote for the now defunct Python Magazine, and is now working on a database e-book. Away from the writing pile, JC spends quality time with his charming foster nephew. He can be reached at anarakisware-at-gmail-dot-com.
Article Description: No description available.
Article Length (in bytes): 43,110
Starting Page Number: 47
Article Number: 9208
Resource File(s):

Download Icon 9208project.zip Updated: 2011-01-06 10:03:25

Related Web Link(s):


Excerpt of article text...

The last time we looked at hash functions, we learned that these functions fall into one of two groups: general-purpose and cryptographic. We learned the traits of a good hash function and how to test for those traits. And we got to survey a handful of general-purpose functions.

Now we shift our focus to those functions that make up the cryptographic group. First, we learn what a function needs to belong to that group. Then we explore a handful of uses for cryptographic hash functions. Next, we study three types of hash functions, divided in terms of origins. We learn how each function behaves and how each one measures up against an avalanche test.

When Hashes Get Secure

Cryptographic hash functions share traits that are unique amongst hash algorithms. First, their input is often, if not always, in the form of a byte stream. Hash output is a byte stream of fixed length, but some functions are able to emit variable-length hashes. Cryptographic hash functions run slower than their general-purpose cousins. On the other hand, they are less likely to suffer from collisions.

Uses for cryptographic hashes

Because of their greater resistance to collisions, cryptographic hash functions play an important role in many security applications. One popular use is in validating critical data.

...End of Excerpt. Please purchase the magazine to read the full article.