To ensure the integrity of the response, you must compare the value of the signature field received in the response with the one computed previously.
If the signatures match,
- you may consider the response as safe and proceed with the analysis.
- If they don't, the script will have to throw an exception and warn the merchant
The signatures may not match because of :
- an implementation error (error in your calculation, problem with UTF-8 encoding, etc.),
- an error in the value of the key or in the vads_ctx_mode (field value (frequent issue when going to live mode),
- a data corruption attempt.