Skip to content

Search

"POS transactions"

280 articles found

Credit card statement showing an unrecognized transaction

Credit Card

Is Your Card Making Purchases Without Your Knowledge?

While reviewing your credit card statement, you suddenly notice a transaction you never made. What would you think? Is your card going shopping while you sleep? Let's look at how this can happen and what to do about it.

Diagram of PIN Encryption Key (PEK) structure

HSM & Security

What is PEK (Pin Encryption Key)?

PEK is the abbreviation for Pin Encryption Key. The role of PEK is to encrypt PINs. There are two types of PEK: TPK (Terminal Pin Key) and ZWK (Zone Working Key).

Online shopping and e-commerce payment on a laptop with a bank card

Payment Institutions & E-Money

What are the advantages of working with a payment institution?

Online shopping keeps growing, and e-commerce sites must choose between working with a bank or a payment institution. This article explains why a single application and integration with a payment institution can be the better route.

Diagram illustrating the TLV (Tag-Length-Value) data structure

Online & Authorization

What is TLV (Tag-Length-Value)?

TLV is a data storage method used to speed up the parsing of data. For example, reading data from a card's chip at a POS and carrying it through authorization uses the TLV structure.

POS payment terminal illustration

Credit Card

What is Dual Messaging?

When the card-issuing bank and the POS bank are different, first obtaining authorization and then running the clearing process to finalize the transaction is called Dual Messaging. So why is a dual message structure needed?

Diagram showing the pre-authorization closing process flow on a POS terminal

Merchant & POS

What Is Pre-Authorization Closing?

Pre-authorization closing turns a pre-authorized transaction into a financial one, posting it to the merchant and cardholder accounts. See how amounts and available limit are affected.

Diagram of basic payment systems terminology including issuer, acquirer, and authorization

Payment Systems

Basic Terms Used in Payment Systems

Although many important terms are used in payment systems, the expressions below are its cornerstones — the ABCs of payment systems, so to speak. Issuer: the credit card company, usually a bank, that issues the card and tracks debt, credit, bonus points, and other services for the customer.

TR Karekod national QR code logo for payments in Turkey

Merchant & POS

The Logo of Our National QR Code, TR Karekod, Has Been Announced

In the world of payment systems, there are new developments every day in both accepting payments and payment methods. QR code payments will undoubtedly become more common in the coming days, and we will make payments with QR codes in many places.

Payment systems in Türkiye overview

Payment Systems

What Are the Payment Systems in Türkiye?

When we hear “payment systems”, card transactions at POS terminals or ATMs usually come to mind. Let's look together at the payment systems recognized by the Central Bank.

Diagram explaining the System Trace Audit Number (STAN) field in a payment transaction

Merchant & POS

What is a System Trace Audit Number (STAN)?

The System Trace Audit Number (STAN) is a number assigned by the third-party system (ATM or POS) to help uniquely identify a transaction. It is generated in the range 000001 to 999999. Each new authorization message needs a new STAN; retries reuse the original STAN.