standard encryption decryption across different platforms

hey guys i need to implement a standard encryption decryption logic across an entire project platform which has different clients implemented using different platforms as follows:

1. iphone app (objectiv c)
2. website (classic asp)
3. webservice (asp.net)
4. samsung bada app (c++)

the iphone app as well as the website need to send info to webservice using encrypted query strings

the web service then decrypts this and processes the info further

wanted to know the simplest way to achieve this. is there some free and ready to use binary available with an easy to use api to achieve this?

encryption needs to be as secure as possible

开发者_Python百科edited: currently we use AES on the website and webservice front

thnx in advance

Can't this be solved by using HTTPS for the web service?

Luckily encryption algorithms are well defined by standards (at least the good ones), so you should be able to find inter operable implementations for the required platforms. You probably want to use AES for the encryption?

Any idea how you will distribute the keys?