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 correct and proceed with the analysis,
- if they do not, the script will have to throw an exception and warn the merchant (see chapter Processing errors).
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 certificate or in the vads_ctx_mode field value (frequent issue when going to live mode),
- a data corruption attempt.