configuring to Base24 format

[samudrala_99]

hello everybody,
I am a software engineer working in a reputated firm .Our present project is on ATM transactions in which we need to send data in base24 format .Could anybody help in getting information about base24 and its format.
At present i do not know anything about this.
Thank you,
Samudrala_99

[Fordy]

Originally posted by samudrala_99
hello everybody,
I am a software engineer working in a reputated firm .Our present project is on ATM transactions in which we need to send data in base24 format .Could anybody help in getting information about base24 and its format.
At present i do not know anything about this.
Thank you,
Samudrala_99

Never heard of Base24 but I know about Base64....

Basically, its an encoding that allows data to be represented by a representation of only 64 bytes

In its simplest form, you take 3 bytes (8 bit * 3), and split them into 4 sets of 6 bits. Now remember that a byte can be represented by 256 chars using ASCII (2 ^ 8), but these six bit sets can only be represented in 64 possible ways (2 ^ 6)...

So you define an array like so;

"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvw xyz0123456789+/"

and use each of the 6bit sets to represent an offset to this array......

Your data will increase by 33% (3 chars is now encoded into 4 chars), but now the data will only be represented by 64 possible char values......

Now if as the end of the data you dont have enough to create the 3 bytes needed for the encoding, you create what 6 bit sets you can (using padding with zeros to make up the 6 bits on the last byte), and then when you output the encoded bytes, use the '=' to make up the final output needed (there will always be 4 bytes outputted per every 3 inputted)


There is an RFC on MIME that you can download........this will probably give a better explanation than I have

[adrianxw]

I am not aware of a standard base24 format, but we used a base36 format when we were building transactions to/from a mobile fare computer for buses. It was necessary to have the transaction files readable with an ASCII viewer, hence we were unable to exploit the more efficient binary storage.

We basically encoded..

0 = 0
1 = 1
...
9 = 9
A = 10
B = 11
...
Z = 36.

[Fordy]

Originally posted by adrianxw
I am not aware of a standard base24 format, but we used a base36 format when we were building transactions to/from a mobile fare computer for buses. It was necessary to have the transaction files readable with an ASCII viewer, hence we were unable to exploit the more efficient binary storage.

We basically encoded..

0 = 0
1 = 1
...
9 = 9
A = 10
B = 11
...
Z = 36.

Hmm really....maybe I missed the point totally and he is refering to an encoding called Base24 which I dont know anything about

[FillYourBrain]

edit : never mind

[Monster]

Base24 is not a format, its a product name. There are different base24 products, base24-atm, base24-card, etc. Take a look at ACI for more information. The format (communication protocol) is not public and top secret (I think). Don't waste time trying to find documentation about this protocol, because you will not find any. I think the best thing to do is contact ACI and ask for more information.

Good luck,
Monster