in reply to saving datas on client-side cookie file.

What you want to look into is.. CGI::Cookie

It is, quite simple, and works very well.

However you really shouldnt try to store too much information in cookies, that isn't what they were designed for. Rather you could use them to store a session ID and then store the necessary data linked by the session ID on the server. But then this doesnt sound like what you had in mind.