Chan py

I am trying to connect a server to a applet in a securtiy mode,i use the java sandbox to achieve this aim, but once i use it, it is not possible for the applet to be connected to another applet.
I know there is a method that i can "sign" the applet so that it can be connected by another server, but how can i sign it?

Sorry for asking a silly question :
if I want to use DES for data encryption, and the encrypt data is in a length of 80 characters, how long does the key I need to use? And can I defined my own key in anyway, or i need to follow some restriction in order to defined the key ?
If i use trple DES, I know it will use 3 keys in succession, then can i defind all the 3 keys, or it need to let for the engine to do?

Thanks all.
I have tried to implement the RSA algorithm on a palm recently, but I found that it cost too much time for generate the key, (almost loop infinity). Is it the real case? Or I use a wrong method to implement?
I implement the RSA engine on the Palm and found that it spends most of the time on the key generation. Can I make such step done one the server rather than the palm? If it so, then in what way i can make it? (I jsut know that I can use object serialization for java, but it seems to be not supported by J2ME)
thx !

What is the Https supports? How it can improve the security level of SSL ? How to use this channel to achieve the aim of secure tading transaction ?

Except MIDlets, what other interfaces are better to be used ?

Paul,
Why you are not recommended to use MIDlets? Is it not so secure ? or it is not stable ?

Thanks Paul
I have read the book for the chapter talking about BouncyCastle, it has mentioned about the "Message Digest" and "RC4 encryption algorithm" only. I saw that there are many other algorithms appeared in the package downloaded form the bouncycastle.
I am trying to get a secure transaction for stock trading on palm, which algorithm is work better in this aim ?
thanks for any opinion.

Just want to ask one more things, does the Encryption and Decryption methods in the BouncyCastle reach the standard of RSA,
how high the sevurity level it reach? if it is not so high, then is it possible to modify the source code, so that i can reach a more security level, like the SSL in the web browser ?

really sorry for giving out so many silly questions.

Mark,
I have visited BouncyCastle's site, i have downloaded the package, but I can't find any infomation that teaching how to use the package on th palm, are there any web sites that can help ?
thx !

I want to get a wireless communication of Palm with a server, but i want to get this data transmission through a secure way, I know I can use SSL in the J2SD, but ahve no idea on J2ME
can anyone teach me where i can find some free software for which i can reach the aim? Besides, i know BouncyCastle does provide one for J2ME, where i can find the sorce code of it?
and are there any other means that have a better performance ?
thanks a lot !!