Using link strength in knowledge-based authentication

摘要

An improved technique generates questions to authenticate a user as part of a group. Along these lines, a KBA system, upon receiving a request to authenticate a particular user, collects facts having references to users of the group of users. The collected facts, however, may also include references to users not in the group of users. In building a set of questions for the particular user, the KBA system is capable of favoring facts having references to users of the group of users and few, if any, references to users not in the group of users; conversely, the KBA system is capable of discarding facts having too many references to users not in the group of users. The particular user's responses to the set of questions are indicative of whether the particular user belongs to the group.

主权项

1. In a knowledge-based authentication (KBA) system, a method of generating a set of questions, the method comprising:
collecting a set of facts that have references to a population of users; receiving a request to authenticate a particular user claiming to belong to a group of users included in the population of users; in response to the request, identifying a set of group facts, each group fact of the set of group facts being included in the set of facts and having references to users of the group of users; and generating the set of questions from the set of group facts, responses to questions of the set of questions provided by the particular user being indicative of whether the particular user belongs to the group of users; wherein generating the set of questions from the set of group facts includes:
for each group fact of the set of group facts, producing an internal link strength that represents a number of users of the group of users referenced by that group fact;using a group fact of the set of group facts to produce a question of the set of questions when the internal link strength for the group fact is greater than a threshold internal link strength; andnot using the group fact in producing questions of the set of questions when the internal link strength for the group fact is less than the threshold internal link strength.