SIM & Securing Transaction Key in HTML FORM

[dacadomx]

I`m trieng to work out with SIM,

I have ready my html FORM with the next values:

https://test.authorize.net/gateway/transact.dll?x_version=3.1&x_type=AUTH_ONLY&x_amount=1.99&x_card_...

Do it great, Just One importante question about this SIM document page 15:

"MPORTANT: The merchant’s Transaction Key is highly sensitive and should only be known by the payment gateway and the merchant. For this reason it is vital that the Transaction Key is stored securely and separately from the merchant’s Web server. In addition, please note that the merchant’s API Login ID will be visible in the source for the payment form request, but the Transaction Key should never be visible.

HOW should be kept safely hidden the Transaction Key and x_login in a HTML FORM?

Do I have to send them first to my ASP and then add the Transaction Key and x_login?

thanks!

[RaynorC1emen7]

This is not a form post, is an url request, and that make it an AIM.

https://test.authorize.net/gateway/transact.dll?x_version=3.1&x_type=AUTH_ONLY&x_amount=1.99&x_card_...

Read http://developer.authorize.net/guides/SIM/wwhelp/wwhimpl/js/html/wwhelp.htm#href=SIM_Submitting_tran...

for the sample

[dacadomx]

Hello!!

 I am completely new in this. I hope you understand my question.

Right it is a URL, but i have my HTML FORM with the Hidden and text inputs by POST

in this: http://developer.authorize.net/guides/SIM/wwhelp/wwhimpl/js/html/wwhelp.htm#href=SIM_Submitting_tran...

Still my question . . . 

I will send in my HTML FORM by POST the <INPUT TYPE=HIDDEN NAME="x_login" VALUE="the merchant’s API Login ID">

BUT how to send : <% ret = InsertFP (APIloginid, sequence, amount, txnkey) %>

Do you think i have to make a new ASP for get all the values and then add the APIloginid, sequence, amount, txnkey?

I hope you understand what I have said, thanks again!

[RaynorC1emen7]

There are sample code here http://developer.authorize.net/downloads/samplecode/