Patent ID: 8572759
Filing Date: 2013-10-29
Classification: H04L

Abstract:
1. A communication control apparatus including a communication control unit, a process execution circuit, and a plurality of search circuits, comprising: a normal signature list which stores a list of signatures of normal communication to be permitted; an abnormal signature list which stores a list of signatures of communication to be blocked; a first of said search circuits which acquires communication data and searches the normal signature list storing signatures of normal communication to be permitted to check if the signature of the communication data appears in the normal signature list; a second of said search circuits which acquires communication data and searches the abnormal signature list storing signatures of communication to be blocked to check if the signature of the communication data appears in the abnormal signature list; said process execution circuit which passes a communication data when the signature of the communication data appears in the normal signature list storing a list of signatures of normal communication to be permitted; a warning circuit which issues a warning when there is detected communication data of which the signature does not match any signatures of normal communication stored in the normal signature list; a blocking circuit which, when there is detected communication data of which the signature matches a signature of communication to be blocked stored in the abnormal signature list, blocks the communication data; an analysis circuit which generates a determination result indicating whether or not communication data against which a warning has been issued is normal and a determination result indicating whether or not communication data against which a warning has been issued should be blocked, when the first search circuit detects that the communication data does not match any signatures of normal communication stored in the normal signature list and when the second search circuit detects that the communication data does not match any signatures of communication to be blocked stored in the abnormal signature list, as the communication data is sent or received by a terminal infected by a bot; a determination result acquisition unit which acquires, from the analysis circuit, a determination result indicating whether or not communication data against which a warning has been issued is normal and a determination result indicating whether or not communication data against which a warning has been issued should be blocked as the communication data is sent or received by a terminal infected by a bot; a normal signature list update unit which, when the determination result acquisition unit acquires a determination result that communication data against which a warning has been issued is found to be normal, adds the signature of the communication data to the normal signature list; an abnormal signature list update unit which, when the determination result acquisition unit acquires a determination result that communication data against which a warning has been issued should be blocked, adds the signature of the communication data to the abnormal signature list; a rule database which stores IP address of a transmission source, transmission destination or content of a part of the communication data required to be analyzed for constituting a modifiable signature as one of rules among acquired communication data; a third of said search circuits which acquires communication data and searches the rule database to check if the communication data complies with a rule stored in the database; and an extraction unit which, when there is detected communication data complying with a rule stored in the rule database, extracts the communication data; wherein at least two of the first search circuit, the second search circuit and the third search circuit perform searches simultaneously in parallel.