What are the probable difficulties and risk associated with using public infrastructure, such as the Internet, as part of a private business solution?

ING Life (formerly NN Financial) is a leading provider of life insurance products in Canada.The company is based in Ontario and operates out of three regional offices.
Over 2000 brokerage partners market its products [BRUN99, IBM00]. In 1997 most of the brokers relied on fax, phone, and postal services to request policy information.
Response times could sometimes be measured in hours.The company did have a 56-kbps frame relay wide area network, but that only connected the Ontario headquarters to 70 managing general agent offices (Figure III.1).The systems in Ontario converted the frame relay requests to SNA from TCP/IP and routed them to the corporate mainframe in Connecticut.