Payment Gateways are software and servers that transmit Transaction information to Acquiring Banks and responses from Issuing Banks (such as whether a transaction is approved or declined). Essentially, Payment Gateways facilitate communication within banks.
Security is an integral component of all payment gateways, as sensitive data such as Credit Card Numbers need to be protected from any fraudulent parties. The card associations have created a set of rules and security standards which must be followed by anyone with access to card information including gateways. This set of rules and security standards is called the Payment Card Industry Data Security Standard (PCI-DSS or PCI).
Submitting an order is usually completed using HTTPS protocol, which securely communicates personal information through the parties involved in the Transaction. Many Payment Providers, such as 2Checkout, enable Merchants with added options when a cardholder purchases a service or product. Aside from providing the ability for real-time transactions, these providers can help to translate currencies between two parties in different countries, as well as bridge language and payment methods. Payment gateways usually charge those who use them a per transaction fee.
SMS gateways solve a common telecommunications problem, that of different wireless telephony providers using different or proprietary communication protocols. The gateway acts as a relay, translating one protocol into another. Wireless network operators use SMS gateways to connect SMS centers (SMSCs). An SMSC is the portion of a wireless network that handles SMS operations, such as routing, forwarding and storing incoming text messages on their way to desired endpoints.
Along with many commercial software products, open source SMS gateway software can be downloaded online. Kannel, written in C, can make connections to SMSCs, cellular phones and GSM or GPRS modems. Kannel uses an HTTP / HTTPS interface for sending and receiving SMS messages.