How are the Security configuration settings in Payment Pages used? – E-xact HELP DESK

Here's a breakdown:

Setting Name	Affected Parameter(s)	Explanation
HMAC Calculation	x_fp_hash x_MD5_Hash x_SHA1_Hash	This setting determines the encryption algorithm used to generate hash values. Setting it to MD5 means that: merchant must calculate `x_fp_hash` using HMAC-MD5 E-xact will sign the transaction results using MD5 and return it as `x_MD5_Hash` Setting it to SHA1 means that: merchant must calculate `x_fp_hash using HMAC-SHA1` E-xact will sign the transaction results using SHA1 and return it as `x_SHA1_Hash`
Transaction Key	x_fp_hash	The Transaction Key is used by the merchant to generate `x_fp_hash`, which needs to be included as part of the payment request form. The `x_fp_hash` value allows E-xact to validate that the payment request was generated by the merchant's server, and that key parts of the payment request such as amount and timestamp have not been modified by a third party.
Response Key	x_MD5_Hash x_SHA1_Hash	When E-xact sends transaction results to the merchant, we'll sign it with a cryptographic hash and return the hashed value as either `x_MD5_Hash` or `x_SHA1_Hash` depending on the "HMAC Calculation" setting. The merchant can use this value *to verify that the message is coming from E-xact*.