Cryptomathic Blog

The “Four Corners” model, also called the “Four Party Scheme”, is utilized in almost all standard card payment systems across the globe. Here, we talk about that model and explain what kind of hardware security module (HSM) is needed for each of its components involved in the cryptographic process.

In the “four corner model”, acquirers are apparently the less active party as their role seems ‘only’ to forward the transaction flow originating from the merchant to and from the issuer. In the model, the acquirer is the merchant’s bank.

Merchants are one of the corners of the ‘four corner’ model in the payment world. In what follows, we will explain some of the security mechanisms for Merchants to prevent unauthorized transactions and payment card fraud.

An issuer is one of the corners in the ‘four corner’ model. An issuer is a financial organization (e.g. a bank) that produces payment cards and allows the cardholders to use them.

Cardholders (or consumers) are one of the corners of the ‘four corner’ model in the payment card world. Here we take a brief look at the payment security in relation to cardholders.