Text Encoding

**treva26** · 10-28-2007, 11:36 PM

I want to make a very basic text encoder to change a text string to a long number. (Yes I know its not very secure!)

This is what I have so far but I cant get the VLookup to work properly...

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The Text to encode is in A1 and the table to lookup is Y1:Z95

If you have any suggestions of other ways to do it please bear in mind I do need the output to be all numbers, not other odd characters.

**shg** · 10-29-2007, 12:25 AM

Here's part of it working. Make sure to format A3 as text.

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**treva26** · 10-29-2007, 01:55 AM

Cool thanks!

OK here is a copy of my current work book.

It kinda works, just has problems with punctuation marks for some reason.

And I havent been able to implement any kind of key system.

Any ideas or different approaches?

**shg** · 10-29-2007, 10:50 AM

Encryption dates back at least to Julius Caesar, who used number substitution for letters. There have been somewhat more sophisticated methods developed since then, to today's DES, Blowfish, RSA, and RijnDael.

There's lots of info in the web, including various algorithms implemented in Excel.

A simple scheme (but not as simple as Caesar's) will keep all but your most dedicated enemies in the dark.

**treva26** · 10-31-2007, 01:47 AM

Theres a cool little excel thing here:

http://blog.livedoor.jp/andrewe/arch...at_107032.html

and I have attached my modified versions too.

Its still REALLY insecure tho...

I read about hiding your encoded message in an image file, that way people dont even know that there IS a message!

**Myles** · 11-02-2007, 01:17 AM

For what amounts to a surfeit, the following idyllic Function code, coutesy of Bob Bovey, does the trick:

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The first-run ecodes, the second automatically decodes to original. Bob's Code uses Octal representations of byte and transmogrifies them with XOR function.

Like all encoding/decoding utilities, it is not fool-proof as you require 255 passes in a loop to unlock the key.

For a very long time now, I have, by continual usage, found my own custom Encript/Decript code fairly reliable, if ponderous. It is again not 100% fail-safe. The codings can use both positive and negative keys, and thereby sidestep tradition. Again, a different key can be used for any one run -to take care of a single encode/decode session.

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**treva26** · 11-04-2007, 07:56 PM

Nice Miles, thanks.

I have actually now finished my own full version.
It encodes pruely into numbers for error free pasting into emails etc, as was my intention.
It takes a password or phrase.
And uses a nice GUI form too.

Im sure the code is not as efficient as it might be but it works and I think its fairly secure, especially if they dont have the workbook.

It encodes into 4-digit numbers which are then multiplied by a corresponding number in the key (after it is encoded into numbers too). Then the resulting message is jumbled up so the 4 digits of each number are not even in order.

I think that using just numbers might also remove any clues that other systems might leave. Also the fact that it takes 4 digits to represent 1 character.
And of course the password can be any alphanumeric phrase you want (as long as you want).