Method for selectively restricting access to computer systems
US6195698A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 13, 1998 |
| Grant date | Feb 27, 2001 |
| Priority date | — |
| Expiry date | Apr 13, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2221/2133
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A computerized method selectively accepts access requests from a client computer connected to a server computer by a network. The server computer receives an access request from the client computer. In response, the server computer generates a predetermined number of random characters. The random characters are used to form a string in the server computer. The string is randomly modified either visually or audibly to form a riddle. The original string becomes the correct answer to the riddle. The server computer renders the riddle on an output device of the client computer. In response, the client computer sends an answer to the server. Hopefully, the answer is a user's guess for the correct answer. The server determines if the guess is the correct answer, and if so, the access request is accepted. If the correct answer is not received within a predetermined amount of time, the connection between the client and server computer is terminated by the server on the assumption that an automated agent is operating in the client on behalf of the user.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.