encrypted hidden value in a hyperlink

[scorpio222]

hi everyone, i am working on a project, where when a user registers, he would be provided with a link which he can give to anyone and ask them to register. once this new user, uses that link to register, he will be automatically assigned certain points, that was set by the manager while he was registering. i do want to use the POST, GET functionality, because the points value will be clearly seen on the hyperlink and if edited would give the user unlimited points. i want to know if there is any way i can encrypt it or provide a hyperlink is such a format that any user who logs in with that link will get the points set by that manager. how can i achieve this? i am using php and mysql.

[ddymacek]

It's all about design, and you have a lot to think about.
Don't pass the variable in a link. Since you know who the 'manager' is and they are presumably stored on a database somewhere, when you assign them a link to pass out, store that link in a table, in the same table have a points value assigned to that link. Say, link a, 50 pts, link b, 100 pts, or whatever. Then when that link is used for a registration page, look up the stored value of the link points in the database and assign to new user.

[scorpio222]

thanks for your reply. I am thinking that i will use something like datetime which would convert the datetime into something like 20100618160000, which is year 2010,month 06,day 18 and time 16:00:00. i will create a new table where, i will have the fields, dateticks,user_group,company_name,points. the i want it in that format bcoz i will take this number as the primary key of the field and send a link as xyz.com?value=20100618160000.

so when link is clicked i will get this value, look up the table and get the points and asign it to them. how can i get this datetime format like that?