Read this FAQ from worldpay about their security
How secure is WorldPay?
WorldPay uses state of the art security tools and techniques, both proprietary
and unique, to ensure that you and your shopper are protected against what
is nowadays a virtually non-existent risk. Our systems also have inbuilt system
redundancy and fault tolerance, to provide you with a virtually uninterrupted
service 24 hours a day, seven days a week. Our systems have evolved over many
years and throughout our history we have continuously sought and gained bank
approval for our systems. technical/security financial/customers products/services
fraud prevention
If the shopper keys in their card details at home or in the office, surely
they are not encrypted until after they arrive at the WorldPay system?
Using industry standard SSL, Thawte and WorldPay unique encryption systems,
this is not actually the case. When the shopper fills in the payment form
and clicks the submit button, their details are not sent straight away. What
actually happens is that a secure link is set up between the shopper's browser
and WorldPay and an encryption code is requested and received, which then
wraps the order and transaction details before leaving the shoppers premises.