Scheme for authentication and dynamic key exchange

• US 20030051140A1
• Filed: 09/10/2002
• Published: 03/13/2003
• Est. Priority Date: 09/13/2001
• Status: Active Grant

• Current Assignee: Alcatel-Lucent SA (Nokia Corporation)
• Original Assignee: Alcatel-Lucent SA (Nokia Corporation)
• Inventors: Garay, Juan A., Buddhikot, Milind M., Miller, Scott C., Salgarelli, Luca
• Granted Patent: US 8,140,845 B2
• Time in Patent Office: Days
• US Class Current: 713/169
• CPC Class Codes: H04L 2209/80 Wireless network architectures or network communication protocols for wireless network security H04W12/00
• CPC Class Codes: H04L 63/062 for key distribution, e.g. centrally by trusted party cryptographic mechanisms or cryptographic arrangements for key distribution involving a central third party H04L9/0819
• CPC Class Codes: H04L 63/068 using time-dependent keys, e.g. periodically changing keys cryptographic mechanisms or cryptographic arrangements for controlling usage of secret information H04L9/088
• CPC Class Codes: H04L 63/08 for authentication of entities cryptographic mechanisms or cryptographic arrangements for entity authentication H04L9/32
• CPC Class Codes: H04L 9/0838 Key agreement, i.e. key establishment technique in which a shared key is derived by parties as a function of information contributed by, or associated with, each of these network architectures or network communication protocols for key exchange in a packet data network H04L63/061
• CPC Class Codes: H04L 9/3273 for mutual authentication network architectures or network communication protocols for achieving mutual authentication in a packet data network H04L63/0869
• CPC Class Codes: H04W 12/0431 Key distribution or pre-distribution; Key agreement
• CPC Class Codes: H04W 12/06 Authentication
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

A scheme for authentication, dynamic key generation and exchange provides means for authentication of mobile nodes and networks, and for generation of per session, per node, security association and encryption keys for encrypting/decrypting communications between a mobile node and an access point in wireless local area networks. The scheme utilizes the same infrastructure and authentication information for both data link layers (layer 2) and network layers (layer 3). This scheme is particularly applicable to networks adhering to the IEEE 802 LAN family of standards.

Claims

1. A method for generating a security key for a mobile node, said method comprising the steps of:

generating a first authenticator at said mobile node in response to a request for authentication, said first authenticator being a function of a first random number, a second random number, a network access identifier for said mobile node, a predetermined security key, an access point identifier, and a session identifier, wherein;

said session identifier and said second random number are randomly generated at said mobile node;

generating an interim second authenticator at said mobile node as a function of said second random number, said first random number, said network access identifier for said mobile node, said predetermined security key, said access point identifier, and said session identifier;

comparing said interim second authenticator with a second authenticator at said mobile node; and

if said interim second authenticator matches said second authenticator, generating said security key for said mobile node at said mobile node as a function of said predetermined security key and said second authenticator.

2. A method in accordance with claim 1, further comprising the steps of:

receiving at said mobile node a first signal indicative of said first random number;

receiving at said mobile node a second signal indicative of said second authenticator;

receiving at said mobile node a third signal indicative of said access point identifier;

providing from said mobile node a fourth signal indicative of said first authenticator and said second random number; and

providing from said mobile node a fifth signal indicative of said session identifier and said network access identifier for said mobile node.

3. A method in accordance claim 2, wherein:

said third signal is further indicative of a request for identification.

4. A method in accordance with claim 3, wherein:

said fifth signal is provided in response to receipt of said third signal; and

said fourth signal is provided in response to receipt of said first signal.

5. A method in accordance claim 1, wherein said security key is an ephemeral security key configured to encrypt and decrypt communications with said mobile node for a current session.

6. A method in accordance claim 1, wherein said security key is an ephemeral security key configured to derive other ephemeral security keys for generating a temporary security association with said mobile node.

7. A method for generating a security key for an access point, said method comprising the steps of:

generating a first random number at said access point;

providing a signal indicative of said first random number from said access point;

receiving a signal indicative of a second random number and a first authenticator at said access point, said first authenticator being a function of said first random number, said second random number, a network access identifier for a mobile node, a predetermined security key, an access point identifier, and a session identifier;

providing a signal indicative of said first authenticator from said access point;

receiving a signal indicative of a second authenticator at said access point, said second authenticator being a function of said second random number, said first random number, said network access identifier for a mobile node, said predetermined security key, said access point identifier, and said session identifier;

wherein;

said security key for said access point is a function of said second authenticator and said predetermined security key; and

providing a signal indicative of said second authenticator from said access point.

8. A method in accordance with claim 7, wherein said security key is an ephemeral security key configured to encrypt and decrypt communications with said access point for a current session.

9. A method in accordance with claim 7, wherein said security key is an ephemeral security key configured to derive other ephemeral security keys for generating a temporary security association with said access point.

10. A method for authenticating a mobile node and a network comprising an access point, and for establishing a temporary security association between said mobile node and said network, said method comprising the steps of:

receiving, at said mobile node, a signal indicative of a request for identification and an access point identifier;

conveying a signal indicative of a mobile node network access identifier and a session identifier from said mobile node to said network in response to said request for identification, wherein;

said session identifier is randomly generated by said mobile node;

generating a first random number at said network;

conveying a signal indicative of said first random number from said network to said mobile node;

generating a second random number at said mobile node;

generating a first authenticator as a function of said first random number, said second random number, said mobile node network access identifier, a predetermined security key, said access point identifier, and said session identifier;

conveying a signal indicative of said first authenticator and said second random number from said mobile node to said network;

generating an interim first authenticator as a function of said first random number, said conveyed second random number, said mobile node network access identifier, said access point identifier, said session identifier, and said predetermined security key;

comparing said first authenticator with said interim first authenticator;

if said first authenticator matches said interim first authenticator,

generating a second authenticator as a function of said second random number, said first random number, said network access identifier, said access point identifier, said session identifier, and said predetermined security key;

generating a security key as a function of said predetermined security key and said second authenticator, at said network;

conveying a signal indicative of said second authenticator from said network to said mobile node;

generating an interim second authenticator as a function of said second random number, said first random number, said mobile node network access identifier, said access point identifier, said session identifier, and said predetermined security key;

comparing said second authenticator with said interim second authenticator; and

if said second authenticator matches said interim second authenticator, generating said security key at said mobile node.

11. A method in accordance with claim 10, wherein:

said security key is an ephemeral security key configured to encrypt and decrypt communications between said mobile node and said network for a current session.

12. A method in accordance with claim 10, wherein:

said security key is an ephemeral security key configured to derive other ephemeral security keys for generating a temporary security association between said mobile node and said network.

13. A mobile node for generating a security key, said mobile node comprising:

a mobile node transmitter/receiver portion configured to;

receive at least one signal indicative of at least one of a first random number, an access point identifier, and a second authenticator; and

provide at least one signal indicative of at least one of a second random number, a first authenticator, a session identifier, and a network access identifier for said mobile node;

a mobile node authenticator processor configured to;

generate said first authenticator as a function of said first random number, said second random number, said network access identifier for said mobile node, said access point identifier, said session identifier, and a predetermined security key; and

generate an interim second authenticator as a function of said second random number, said first random number, said network access identifier for said mobile node, and said predetermined security key; and

compare said second authenticator with said interim second authenticator; and

a mobile node key generator configured to generate said security key as a function of said predetermined security key and said second authenticator, if said second authenticator matches said interim second authenticator.

14. A network for generating a security key, said network comprising:

a network transmitter/receiver portion configured to;

receive at least one signal indicative of at least one of a second random number, a first authenticator a network access identifier, and a session identifier, wherein;

said first authenticator is a function of a first random number, said second random number, said network access identifier, said session identifier, an access point identifier, and a predetermined security key; and

provide at least one signal indicative of at least one of said first random number and a second authenticator, and said access point identifier, wherein;

said second authenticator is a function of said second random number, said first random number, said network access identifier, said access point identifier, said session identifier, and said predetermined security key;

a network authenticator processor configured to;

generate an interim first authenticator as a function of said first random number, said second random number, said network access identifier, said access point identifier, said session identifier, and said predetermined security key; and

compare said first authenticator with said interim first authenticator; and

if said first authenticator matches said interim first authenticator, generate said second random number and said second authenticator; and

a network key generator configured to generate said security key as a function of said predetermined security key and said second authenticator, wherein;

said security key is an ephemeral security key configured to encrypt and decrypt communications with said network for a current session,

15. A network in accordance with claim 14, wherein said security key is an ephemeral security key configured to derive other ephemeral security keys for generating a temporary security association with said mobile node.

16. A system for authenticating a mobile node and a network, and for establishing a temporary security association between said mobile node and said network, said system comprising:

a mobile node comprising;

a mobile node transmitter/receiver portion configured to;

receive at least one signal indicative of at least one of a first random number, an access point identifier, and a second authenticator; and

provide at least one signal indicative of at least one of a second random number, a first authenticator, a session identifier, and a network access identifier for said mobile node;

a mobile node authenticator processor configured to;

generate said first authenticator as a function of said first random number, said second random number, said network access identifier for said mobile node, said access point identifier, said session identifier, and a predetermined security key; and

generate an interim second authenticator as a function of said second random number, said first random number, said network access identifier for said mobile node, and said predetermined security key; and

compare said second authenticator with said interim second authenticator; and

a mobile node key generator configured to generate said security key as a function of said predetermined security key and said second authenticator, if said second authenticator matches said interim second authenticator; and

a network comprising;

a network transmitter/receiver portion configured to;

receive at least one signal indicative of at least one of the first authenticator, the second random number, the network access identifier for the mobile node, and the session identifier; and

provide at least one signal indicative of at least one of said first random number, said second authenticator, and said access point identifier;

a network authenticator processor configured to;

generate an interim first authenticator as a function of said first random number, said second random number, said network access identifier, said access point identifier, said session identifier, and said predetermined security key; and

compare said first authenticator with said interim first authenticator; and

if said first authenticator matches said interim first authenticator, generate said second authenticator; and

a network key generator configured to generate said security key as a function of said predetermined security key and said second authenticator, wherein;

said security key is an ephemeral security key configured to encrypt and decrypt communications between said mobile node and said network for a current session.

17. A system in accordance with claim 16, wherein, said security key is an ephemeral security key configured to derive other ephemeral security keys for generating a temporary security association between said mobile node and said network.

18. A computer readable medium encoded with a computer program code for directing a processor to generate a security key for a mobile node, said program code comprising:

a first code segment for causing said processor to receive at least one signal indicative of at least one of a first random number and an access point identifier;

a second code segment for causing said processor to generate a second random number;

a third code segment for causing said processor to generate a first authenticator as a function of said first random number, said second random number, a network access identifier for said mobile node, said access point identifier, a session identifier, and a predetermined security key;

a fourth code segment for causing said processor to provide at least one signal indicative of at least one of said network access identifier for said mobile node, said session identifier, said first authenticator, and said second random number;

a fifth code segment for causing said processor to receive a signal indicative of a second authenticator;

a sixth code segment for causing said processor to generate an interim second authenticator as a function of said second random number;

a seventh code segment for causing said processor to compare said interim second authenticator with said second authenticator; and

an eighth code segment for causing said processor to generate said security key as a function of said predetermined security key and said second authenticator, if said interim second authenticator matches said second authenticator.

19. A computer readable medium encoded with a computer program code for directing a processor to generate a security key for a network, said program code comprising:

a first code segment for causing said processor to generate a first random number;

a second code segment for causing said processor to provide at least one signal indicative of at lest one of said first random number and an access point identifier;

a third code segment for causing said processor to receive at least one signal indicative of at least one of a first authenticator, a second random number and a session identifier, wherein;

said first authenticator is a function of said first random number, said second authenticator, a network access identifier, a session identifier, said access point identifier, and a predetermined security key;

a fourth code segment for causing said processor to generate an interim first authenticator as a function of said first random number, said second authenticator, said network access identifier, said access point identifier, said session identifier, and said predetermined security key;

a fifth code segment for causing said processor to compare said first authenticator with said interim first authenticator; and

if said first authenticator matches said interim first authenticator,

generate a second authenticator as a function of said second random number, said first random number, said network access identifier, said access point identifier, said session identifier, and said predetermined security key;

a sixth code segment for causing said processor to provide a signal indicative of said second authenticator; and

a seventh code segment for causing said processor to generate said security key as a function of said predetermined security key and said second authenticator.

20. A computer readable medium encoded with a computer program code for directing a processor to authenticate a mobile node and a network, and for establishing a temporary security association between said mobile node and a network, said program code comprising:

a first code segment for causing said processor to generate a first random number;

a second code segment for causing said processor to convey at least one signal indicative of at least one of said first random number and an access point identifier from said network to said mobile node;

a third code segment for causing said processor to generate a second random number, a first authenticator and a session identifier, wherein;

said first authenticator is a function of said first random number, said second random number, a network access identifier for said mobile node, said access point identifier, said session identifier, and a predetermined security key;

a fourth code segment for causing said processor to convey at least one signal indicative of at least one of said second random number, said first authenticator and said session identifier from said mobile node to said network;

a fifth code segment for causing said processor to generate an interim first authenticator as a function of said first random number, said second random number, said network access identifier for said mobile node, said access point identifier, said session identifier, and said predetermined security key;

a sixth code segment for causing said processor to compare said first authenticator with said interim first authenticator;

a seventh code segment for causing said processor to generate a second authenticator as a function of said second random number, said first random number, said network access identifier for said mobile node, said access point identifier, said session identifier, and said predetermined security key;

an eighth code segment for causing said processor to generate a security key as a function of said predetermined security key and said second authenticator, wherein;

said security key is an ephemeral security key configured to at least one of;

encrypt and decrypt communications between said mobile node and said network for a current session; and

derive other ephemeral security keys for generating a temporary security association between said mobile node and said network;

a ninth code segment for causing said processor to convey a signal indicative of said second authenticator from said network to said mobile node;

an tenth code segment for causing said processor to generate an interim second authenticator as a function of said conveyed second random number, said first random number, said network access identifier for said mobile node, said access point identifier, said session identifier, and said predetermined security key;

an eleventh code segment for causing said processor to compare said second authenticator with said interim second authenticator; and

a twelfth code segment for causing said processor to generate said security key at said mobile node if said second authenticator matches said interim second authenticator.