Certificate management was difficult on the wide-open Internet, and intranets are so tightly controlled that many alternatives are available. However, over the last year, a number of innovative extranet implementations of the technology have been announced, suggesting that certificates are a workable solution for the problems raised by this networking medium. Since the members of this network can be both competitors and partners, they need to be able to draw secure perimeters around any group. The network establishes a single networkwide certification authority that any member can use to authenticate data requests from any other member. At the same time, any company can issue its own private certificates, allowing it to raise security barriers against the other members.
Digital certificates are also flexible.
The New Zealand Ministry of Health is completing a system in which all the country's health care providers, from rural clinics to urban hospitals, will use digital certificates to authenticate requests for patient information. Ensuring the privacy of this information is important. In order to qualify for one of these certificates, an applicant must present himself physically at an office, show a real passport and fill out 30 pages of forms, according to Yogesh Anand, information systems manager at the New Zealand Health Information Service, a group within the Ministry. Probably the largest implementation of the technology to date is by Scotiabank of Toronto, which is using digital certificates to authenticate one-stop access by 100,000 of its customers to all the bank's services from balance checking to funds purchases. These certificates will not reveal the user's name and address even if the codes protecting their contents are broken.