# US 9,439,072 B2 · System and method for authentication

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- Number: US 9,439,072 B2
- Document ID: US9439072B2
- Status: Granted
- Kind: B2
- Application number: 14/753,993
- Filed: 2015-06-29
- Published: 2015-10-22
- Granted: 2016-09-06
- Earliest claimed: 2013-11-08
- Assignees: Teamblind Inc.
- Applicants: Teamblind Inc.
- Inventors: Seong Uk Moon; Yeong Jun Jeong
- Web page: https://patentgrep.com/patent/US9439072B2

## CPC

- H04W 12/06: Authentication
- H04L 51/18: Commands or executable codes
- H04L 63/065: {for group communications (cryptographic mechanisms or cryptographic arrangements for key management involving conference or group key H04L9/0833)}
- H04L 63/18: {using different networks or channels, e.g. using out of band channels (cryptographic mechanisms or cryptographic arrangements for key distribution involving distinctive intermediate devices or communication paths H04L9/0827; cryptographic mechanisms or cryptographic arrangements for authentication using a plurality of channels H04L9/3215)}
- H04W 12/04: Key management, e.g. using generic bootstrapping architecture [GBA]
- H04W 12/73: Access point logical identity
- H04W 84/12: WLAN [Wireless Local Area Networks]
- H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72)
- H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M)

## Abstract

Provided is a system and method for authentication. The method includes receiving a subscription request from a user terminal, the subscription request executed by an authentication server communicating with the user terminal and including group discrimination data including a group code and information for discriminating a group from another, if it is determined that the group code and the information included in the group discrimination data correspond to each other, performing a group authentication procedure on the user terminal and processing the group authentication procedure as being successful, issuing a member session key to the user terminal, and providing a service requested by the user terminal in response to the service request including the member session key from the user terminal. In one embodiment, it is possible to prevent information on service users from being divulged.

## Claims

### Claim 1

A method for authentication comprising:
receiving a subscription request from a user terminal, the subscription request including a group code and a plaintext e-mail address;
storing the plaintext e-mail address included in the subscription request in a table for subscription;
when the group code and the plaintext e-mail address correspond to each other, performing a group authentication procedure on the user terminal;
when the group authentication procedure for the user terminal is successful:
issuing an authentication key for the subscription request and storing the authentication key in the table for subscription;
transmitting the authentication key to the user terminal;
receiving, from the user terminal, member information including an encrypted plaintext e-mail address of the user with the authentication key;
searching the plaintext e-mail address using the authentication key in the table for subscription;
encrypting the searched plaintext e-mail address using a same encryption logic used when an encrypted e-mail address recorded in the table for redundancy removal is encrypted ; and
checking whether the encrypted searched plaintext e-mail address exists in a table for redundancy removal;
when the encrypted searched plaintext e-mail address exists in the table for redundancy removal, transmitting a redundancy message to the user terminal;
when the encrypted searched plaintext e-mail address is not in the table:
issuing a member session key and e-mail session key;
storing the encrypted searched plaintext e-mail address and e-mail session key in the table for redundancy removal;
storing the encrypted plaintext e-mail address in the member information and the member session key in a table for members;
transmitting the member session key and the e-mail session key, to the user terminal; and
deleting data of the table for subscription for the subscription request; and
providing a service requested by the user terminal in response to a service request including the member session key and the e-mail session key when the member session key is in the table for members and the e-mail session key is in the table for redundancy removal.

### Claim 2 (depends on 1)

The method of claim 1, wherein the group authentication procedure comprises sending an e-mail including an authentication code to the plaintext e-mail address if the group code and a host information included in the plaintext e-mail address correspond to each other; and
processing the group authentication procedure for the user terminal as being successful if discrimination of the authentication code included in the sent e-mail is detected.

### Claim 3 (depends on 1)

The method of claim 1, wherein the group authentication procedure comprises providing the user terminal with information on a receiving mail address to which an authentication e-mail is to be addressed if the group code and a host information included in the plaintext e-mail address correspond to each other; and processing the group authentication procedure for the user terminal as being successful if the authentication e-mail is received in the receiving mail address as a recipient.

### Claim 4 (depends on 1)

The method of claim 1, wherein receiving a subscription request comprises receiving at least one of an identifier of a wireless LAN access point which the user terminal is capable of access and position information of the user terminal.

### Claim 5 (depends on 1)

The method of claim 1, wherein the member information of the user includes an encrypted password and the plaintext e-mail address encrypted by the password from the user terminal, and
the receiving member information comprises, recording the received member information in the table for members before deleting the data.

### Claim 6 (depends on 1)

The method of claim 1, wherein the receiving of the subscription request comprises receiving the subscription request together with a push identifier of the user terminal.

### Claim 7 (depends on 6)

The method of claim 6, wherein the receiving of the subscription request further comprises storing the group code and the plaintext e-mail address included in the subscription request and received together, and the push identifier in the table for subscription.

### Claim 8 (depends on 1)

The method of claim 1, wherein the receiving of the subscription request comprises:
generating the authentication key to be issued to the user terminal so as to correspond to the subscription request.

### Claim 9 (depends on 8)

The method of claim 8, wherein the group authentication procedure as being successful comprises transmitting an e-mail confirmation notification including the authentication key to the user terminal using a push identifier after the processing of the group authentication procedure as being successful.

### Claim 10 (depends on 9)

The method of claim 9, wherein the receiving of the member information comprises transmitting a response indicating that the group authentication has been successfully completed to the user terminal if an authentication request including the authentication key from the user terminal is received.

### Claim 11 (depends on 9)

The method of claim 9, wherein the issuing of the member session key comprises confirming the plaintext e-mail address registered in the table for subscription so as to correspond to the authentication key received from the user terminal, generating the e-mail session key corresponding to the confirmed plaintext e-mail address.

### Claim 12 (depends on 1)

The method of claim 1, wherein the receiving of the member information comprises:
confirming whether the encrypted plaintext e-mail address is identical with the stored encrypted e-mail address in the table for redundancy removal;
if the encrypted plaintext e-mail address is identical with the stored encrypted e-mail address in the table for redundancy removal, notifying the user terminal of a redundant subscription request to determine whether to proceed an authentication procedure; and
if there is a request for authentication procedure from the user terminal, renewing and storing the e-mail session key corresponding to the encrypted plaintext e-mail address is identical with the stored encrypted e-mail address in the table for redundancy removal.

### Claim 13 (depends on 1)

The method of claim 1, wherein the providing of the service comprises:
receiving the service request including the member session key and the encrypted password from the user terminal;
confirming from the table for members the recorded encrypted password so as to correspond to the member session key; and
providing the service requested by the user terminal only when the encrypted password included in the service request is identical with the encrypted password recorded in the table for members.

### Claim 14

A non-transitory computer-readable medium with instructions stored therein which upon execution instruct at least one processor to:
receive a subscription request from a user terminal, the subscription request including a group code and a plaintext e-mail address;
store the plaintext e-mail address included in the subscription request in a table for subscription;
when the group code and the plaintext e-mail address correspond to each other, perform a group authentication procedure on the user terminal and processing the group authentication procedure as being successful;
when the group authentication procedure for the user terminal is processed successfully:
issue an authentication key for the subscription request and storing the authentication key in the table for subscription;
transmit the authentication key to the user terminal;
receive, from the user terminal, member information including an encrypted plaintext e-mail address of the user with the authentication key;
search the plaintext e-mail address using the authentication key in the table for subscription;
encrypt the searched plaintext e-mail address using the same encryption logic used when an encrypted e-mail address recorded in the table for redundancy removal is encrypted; and
check whether the encrypted searched plaintext e-mail address exists in a table for redundancy removal;
when the encrypted searched plaintext e-mail address exists in the table for redundancy removal, transmit a redundancy message to the user terminal;
when the encrypted searched plaintext e-mail address is not in the table for redundancy removal:
issue a member session key and e-mail session key;
store the encrypted searched plaintext e-mail address and e-mail session key in the table for redundancy removal;
store the encrypted plaintext e-mail address in the member information and the member session key in a table for members;
transmit the member session key and the e-mail session key, to the user terminal; and
delete the data of the table for subscription for the subscription request; and
provide a service requested by the user terminal in response to a service request including the member session key and the e-mail session key, only when the member session key is exist in the table for members and the e-mail session key is exist in the table for redundancy removal.