Search
87 articles found
Credit Card
Due to how payment systems work, authorization is obtained first for a transaction. For a Not Onus transaction (where the card-issuing bank and the POS bank are different), the system waits for the relevant transaction to arrive via the clearing incoming file…
ISO 8583
F25 - POINT OF SERVICE (POS) CONDITION CODE is the field that defines the condition under which a POS transaction was performed. Possible values include 00 Normal presentment, 01 Customer not present, 02 Unattended terminal, and more.
Merchant & POS
In payment systems, an online transaction means the transaction is sent to the card or POS/ATM bank at the moment it occurs, and required checks are obtained from that system. So does every transaction happen online? Of course not. Especially with contactless...
HSM & Security
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).
Debit Card
A prepaid card is a customized card that is not linked to a bank account and has no credit limit like a credit card - you can spend only up to the amount loaded onto it. Prepaid cards function just like a bank card or credit card.
Credit Card
In the standard authorization flow, the transaction is initiated by the acquirer (POS bank) and forwarded to the issuer (card-issuing institution). The process is completed once the issuer responds. However, this isn't always possible; when the issuer fails to respond, BKM steps in...
Contactless
It is important to use contactless cards to prepare our payment habits for the future. In Turkey, one in every 3 cards and one in every 4 POS terminals is contactless-enabled, yet usage remains around 5%.
Credit Card
PVV is the number encoded on a card's magnetic stripe that allows the cardholder's PIN to be verified by ATMs and POS terminals. It is a 4-digit cryptogram calculated through a cryptographic operation using the PIN and card data. The real result is longer than 4 digits.
Merchant & POS
A Card Recovery Bulletin is a list of problem cards (lost, stolen, expired, over-limit, counterfeit or otherwise flagged) published by card schemes such as Visa or MasterCard. It shows whether a card number is listed on the date of purchase.
Clearing
The Domestic Clearing and Settlement System (YTH) settles and clears transactions between two banks when a card from one bank is used at another bank's POS or ATM. Participants submit records that are cleared daily and multilaterally netted and reconciled.
HSM & Security
ZWK stands for Zone Working Key. It encrypts the PIN so that it can travel securely between different financial institutions, such as the acquiring bank and the issuing bank.
Chargeback
A chargeback is when a cardholder asks the issuing bank to refund a transaction made without their knowledge. It cannot be prevented entirely, but simple precautions can minimize the risk. Here is how the process works and what cardholders should do.