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With over 257 billion card transactions for goods and services worldwide, the payment cards (credit or debit cards) serve as one of the most preferable modes of payment. In fact, many surveys show that over 70% people prefer card payments over cash.

Payment Card - PCI DSS

While alternate modes of payment are catching up (such as IBAN in Europe, UPI in India etc.), the card industry will continue to thrive for several years, on account of its worldwide acceptance, transaction success rate and ease of use.

Of course, like all other electronic media, security is of paramount importance when it comes to payment cards. While there is a legal structure for protecting the interests of the card users, the underlying security (both infrastructure and application) is governed by PCI DSS compliance.

So what is PCI DSS?

It stands for Payment Cards Industry - Data Security Standards. Five different companies Visa, MasterCard, American Express, Discover and JCB International - each of them who already had their individual security policies - aligned together to form PCI DSS compliance, with the aim:

" To protect their interests by making merchants (e-commerce websites etc.) comply with minimum (acceptable) level of security while storing, processing and transmitting card holder data."

There have been several revisions to these standards and the latest version 3.2.1 was ratified and released in May 2018.

The complete PCI DSS checklist can be found here.

PCI Stake Holders

Payment Brands - The financial institutions viz. Visa, MasterCard, American Express, Discover and JCB who are responsible for advancing and promoting the PCI DSS

Acquirer - Bank or a financial institution that maintains the account of the merchant and which processes transactions.

Approved Scanning Vendor (ASV) - Company approved by PCI SSC to conduct external vulnerability scanning services. The list of ASVs can be found here:

Merchant - This is the e-commerce website that accepts card payments


  1. The customer purchases goods or avails services from an e-commerce website. Here, the owner of the e-commerce website is the "Merchant"
  2. The customer uses his credit / debit card to pay for the goods or services. The credit / debit card is issued to the customer by an "Issuing Bank". To simplify, if you used ABN AMRO's credit card to pay for the goods (i.e. if the card reads ABN AMRO), the "Issuing Bank" here, will be ABN AMRO.
  3. The transaction details are immediately processed by the merchant's Acquirer. The acquirer sends the transaction details to the Credit Card Network (Visa, MasterCard etc.)
  4. The credit card network clears the payment and requests payment authorization from the issuing bank. The authorization request includes the following:
    • Payment Amount
    • Credit card Number
    • Card Expiration date
    • Billing address - for Address Verification System (AVS) validation
    • Card security code such as CVV
  5. The issuing Bank checks the above authorization, checks for the account balance and clears the transaction.

Next we will check the PCI DSS compliance checklist.


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