Hello, 
Yes I did try that and that was what happened, I have attached a jpg that also 
shows it if your curious about the graphic. My understanding however is that 
CBC should be able to recover from lost data (not just a few bad bytes or bits) 
- if the data is lost the decryption algorithm would have no a priori knowledge 
and therefore be lost and I wouldn't know where to pad it on the other end. Can 
you give me a bit more on the alignment - how and why does the alignment occur? 

Thanks - I appreciate the help, 
Anthony 

----- Original Message ----- 
From: "Phillip Hellewell" <[email protected]> 
To: [email protected] 
Sent: Wednesday, May 5, 2010 10:07:53 AM GMT -05:00 US/Canada Eastern 
Subject: Re: Cipher Block Chaining 

On Wed, May 5, 2010 at 7:07 AM, Anthony Gabrielson 
<[email protected]> wrote: 
> works. So I'm curious whats going on - ism y understanding of CBC mistaken? 

You need to keep things aligned for it to work properly. Try 
replacing the first 7 bytes with 0 rather than removing them and 
shifting everything over. You should only lose the first block and 
part of the second if I am not mistaken. 

Phillip 
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