## Payment

If you have a Premium Mix, you may setup your payment configuration options using this panel.

### JPI Certificate

This is the certificate of the payment instance that your Mix contacts to settle user payments.

Please leave the default certificate unchanged if you do not need to.

### Price Certificate

By issuing this certificate, the payment instance provider guarantees you a certain price per anonymised GB for your Mix traffic. An anonymised GB is about 2 normal GB, as the user's traffic has to go in and out of your Mix. Please note that the payment instance provider may invalidate price certificates, for example if you have requested a new one: in this case, users will not be able to connect to your Mix until you have set a new valid price certificate.

A price certificate is issued on each of your Mix certificates. If you want a new Mix to be registered at the payment system, you therefore have to send your public Mix certificate (.cer file, X509) to the payment instance provider.

### JPI (Java Payment Instance)

Enter the hostname, port and id of the Payment Instance you want to use for settling your cost confirmations

Please do not change the default values if you do not need to.

### General Settings

- SoftLimit (Bytes) The SoftLimit tells the Accounting Instance when to ask a connected JAP for a signed cost confirmation. Everytime the number of bytes in this field has been transferred between the mix and the JAP, the JAP must send this cost confirmation.
- HardLimit (Bytes) The HardLimit is the number of bytes that may be transmitted without receiving a cost confirmation from the JAP. When the HardLimit is reached, the mix will cut the connection to the JAP. HardLimit should be much greater than SoftLimit.
- Prepaid Interval (bytes) The (maximum) number of bytes that a user has to pay before he is allowed to use the Mix.
- SettleInterval (seconds) The settle interval tells the Accounting Instance how often to contact the Payment Instance to settle cost confirmations. The longer this interval, the less the communication effort and the less the accuracy of the displayed balance in the JAP.

Please do not change the default values if you do not need to.

### PostgreSQL database for accounting

For accounting to function properly, your Mix will need access to a PostgreSQL database. Enter the correct data for the database here.