SESSION CONTROL SERVER, COMMUNICATION DEVICE, COMMUNICATION SYSTEM AND COMMUNICATION METHOD, AND PROGRAM AND RECORDING MEDIUM FOR THE SAME

• US 20090094692A1
• Filed: 10/03/2008
• Published: 04/09/2009
• Est. Priority Date: 06/19/2003
• Status: Abandoned Application

• Current Assignee: Nippon Telegraph and Telephone Corporation
• Original Assignee: Nippon Telegraph and Telephone Corporation
• Inventors: Sakaya, Seiichi, Ono, Kumiko, Tachimoto, Shinya
• Application Number:
  US12/244,816
• Publication Number:
  US 20090094692A1
• Time in Patent Office: Days
• US Class Current: 726/11
• CPC Class Codes: H04L 2209/60 Digital content management, e.g. content distribution
• CPC Class Codes: H04L 2209/80 Wireless network architectures or network communication protocols for wireless network security H04W12/00
• CPC Class Codes: H04L 9/0825 using asymmetric-key encryption or public key infrastructure [PKI], e.g. key signature or public key certificates
• CPC Class Codes: H04L 9/0891 Revocation or update of secret information, e.g. encryption key update or rekeying
• CPC Class Codes: H04L 9/3263 involving certificates, e.g. public key certificate [PKC] or attribute certificate [AC]; Public key infrastructure [PKI] arrangements network architectures or network communication protocols for supporting authentication of entities using certificates in a packet data network H04L63/0823
• CPC Class Codes: Y04S 40/20 Information technology specific aspects, e.g. CAD, simulation, modelling, system security

Abstract

A communication device, connected via a network so as to be able to communicate with a session control server, and which establishes a session with another communication device by performing signal transmission to and reception from the session control server, includes: a unit which generates an asymmetric key pair; a request unit which requests certificate issuance for a public key in the asymmetric key pair; a receiving unit which receives notification of public key issuance completion from the session control server; a storage unit which stores a public key certificate which has been received; a sending unit which sends a location registration request of a communication device to the session control server; and a receiving unit which receives a location registration completed notification which includes a term of validity from the session control server; and which sends a location registration request and a certificate issuance request as a combined request.

Claims

1-50. -50. (canceled)

51. A communication method in which a session control server changes the filtering conditions of a NAT/firewall device based upon information which has been obtained during establishment of a session, wherein:

the session control server, after having determined a decryption key for decryption, decrypts a first encryption key, and decrypts encrypted information with said first encryption key, thus making it possible to refer to or to change control information between communication devices;

based upon said control information, change of the filtering conditions is requested to the NAT/firewall device;

thereafter, control information between communication devices which has been received from a signal reception side communication device is decrypted, and it is made possible to refer to, or to change, the control information between communication devices; and

based upon said control information, change of the filtering conditions is requested to the NAT/firewall device, and mutual packet passage for main information between communication devices is performed by the NAT/firewall device.

52. A communication method in which a session control server makes it possible to record communication of main information which has been encrypted, based upon information which has been obtained during establishment of a session, wherein:

a session control server, in addition to a request to change filtering conditions to a NAT/firewall device or the like, commands main information transfer, and, when main information is received from the NAT/firewall device or the like, if said main information is encrypted, when transmitting and receiving a signal, decrypts a first encryption key, and decrypts the encrypted information, along with control information between communication devices which has been obtained by decrypting with said first encryption key, by using a key for main information encryption, which has already been obtained, and records said main information in a communication recording unit.

53. (canceled)

54. A program for communication which causes a session control server to change the filtering conditions of a NAT/firewall device, based upon information which has been obtained during establishment of a session, for causing a computer of said session control server to execute:

a procedure of determining a decryption key for decryption;

a procedure of performing decryption of a first encryption key;

a procedure of decrypting encrypted information with said first encryption key, thus making it possible to refer to or to change control information between communication devices;

a procedure of, based upon said control information, requesting change of the filtering conditions to the NAT/firewall device;

a procedure of, thereafter, decrypting control information between communication devices which has been received from a signal reception side communication device, and making it possible to refer to, or to change, the control information between communication devices; and

a procedure of, based upon said control information, requesting change of the filtering conditions to the NAT/firewall device

57. A computer readable recording medium, in which a program for communication according to claim 54 is recorded.

55. A program for communication which causes a session control server to perform recording of communication of main information which has been encrypted, based upon information which has been obtained during establishment of a session, for causing a computer of said session control server to execute:

a procedure of, in addition to a request to change filtering conditions to a NAT/firewall device or the like, commanding main information transfer;

a procedure of receiving main information from the NAT/firewall device or the like;

a procedure of, if said main information is encrypted, when transmitting and receiving a signal, performing decryption of a first encryption key, and decrypting the encrypted information, along with control information between communication devices which has been obtained by decrypting with said first encryption key, by using a key for main information encryption, which has already been obtained; and

a procedure of recording said main information in a communication recording unit.

58. A computer readable recording medium, in which a program for communication according to claim 55 is recorded.

56. (canceled)