The charity plans to roll-out software that will allow social workers, police and local authorities to download confidential case notes from a secure Web site, rather than risk sending files over the Internet.
The NSPCC chose the Web site method after an evaluation of alternative public key encryption systems showed they were complicated to administer and difficult to use, particularly for one-off communications.
Brendan Major, the NSPCC's head of information services, said, "Although a system with public and private keys over the Internet would have been secure, the problem is that it does not work when you have large numbers of casual workers. We might work with a particular policeman or social worker once a year. A PKI system would be difficult to set up and manage."
The Secure Mail package, donated by US supplier Tumbleweed, will automatically divert sensitive e-mails to the charity's secure Web site. Rather than receiving the confidential file directly, social workers or police officers will receive a URL link to the document via e-mail. They will be asked to type in a pre-agreed user name and password to access the information.
Although it is possible to add further protection in the form of digital signature verification, the password and user name represented a good compromise between high security and making the system too difficult to use.
"You have to balance the security of the system with ease of use. If you make it too difficult to use, people will communicate in other ways which are less secure," said Dave Brunswick, Tubleweed's director of European technical services.
The NSPCC said the system will also protect against workers accidentally sending files to the wrong address. "The damage to the reputation of the NSPCC would be colossal if information about a child was sent to the wrong person," said Major.
The NSPCC is running Secure Mail, which uses 128-bit RSA encryption to protect the content of messages, on a central HP Netserver. User and access details are stored on a separate Oracle database.
The charity's 35-strong IT team will maintain the system in-house as part of its commitment to protecting the confidentiality of the children it helps. "It is a question of confidence. We would like to say to children that all information is held on our own servers," said Major.
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