Visa International

Creating a fast, reliable, high-availability, credit card processing network

With a global network of over 2500 individual processing points, VISA International demands maximum security and reliability, but also flexibility to match a global array of different protocol preferences. To satisfy these needs, the customer developed a robust redundant solution with Gcom® protocol technology at its core. Network connectivity devices, known as VisaNet Access Points (VAPs), are deployed worldwide at member banks and other financial institutions, and act as gateways to the credit card network's main transaction clearinghouses (known as Visa Interchange Centers, or VICs).

The key elements of each Gcom-enabled VAP are a synchronous communications adapter and the Gcom Protocol Suite, which includes driver software for the adapter and a full complement of networking protocols. Network members using this solution can access the card processing network using SNA, X.25, Bisync, Token Ring, or IP connections, according to their individual needs.

A typical credit card transaction passes through Gcom-enabled VAPs four times:

• Transaction sent out for authorization (first pass through Gcom solution)
• Transaction sent to VIC, routed to bank that issued user's card (second pass)
• Transaction approval sent back out through the issuing bank's VAP (third pass)
• Transaction approval sent back to merchant's bank via VAP (fourth pass)

Using Gcom technology, VISA International's network handles a peak volume of 5000 transactions per second, and operates 24 hours a day, 7 days a week

Network Topology

• SNA backbone
• Mixed-protocol endpoints
• Mainframe interchange centers

Gcom Solution

• Gcom Protocol Suite with SNA, X.25, Bisync, Frame Relay, and IP
• Synchronous serial adapter

Network Interfaces

• RS-232
• V.35
• X.21
• T1/E1
• EIA530