The problems at Worldpay and Authorize.net have been attributed to distributed denial of service (DDoS) attacks. A series of DDoS attacks in April targeted online payment processing firms Authorize-IT and 2Checkout. Both those attacks were later attributed to extortion schemes in which attackers threatened to knock the firms' web sites offline.
PSIGate has made no public comment as yet about its performance problems.
Posted by Rich Miller in Performance
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