Granted Patent B2

US 8,281,134 · App. 12/361,624 · Granted Oct 2, 2012

Assignee: Symbol Technologies, Inc.

Abstract

Claims (38)

1. A method for providing security for control frames communicated between a first termination point and a second termination point in a wireless local area network, the method comprising:

providing a shared secret to the first termination point and the second termination point;

sending a discovery request to the second termination point;

generating, at the second termination point, a first nonce, encrypting the first nonce using a master key derived from the shared secret, and transmitting the encrypted first nonce to the first termination point in a discovery response;

decrypting the encrypted first nonce in the first termination point using the same master key derived from the shared secret;

generating a second nonce at the first termination point;

concatenating the first and second nonces and encrypting the result using an encryption algorithm and the master key to form an encrypted join request;

sending the encrypted join request to the second termination point;

decrypting the encrypted join request to determine a decrypted first nonce;

if the first nonce is equal to the decrypted first nonce, sending a join response indicative of authentication;

calculating a session key from at least one nonce; and

entering a run state and sending the control frames in accordance with the session key.

2. The method of claim 1 , wherein the session key in the calculating step is derived from the shared secret and the first and second nonces such that the session key is unique for the session despite being generated from the same shared secret.

3. The method of claim 1 , wherein if authentication is received and if pre-staging is enabled for the first termination point, further including sending the shared secret without encryption in the join response to the first termination point from the second termination point, wherein sending the shared secret completes mutual authentication of the two termination points by proving that the two termination points both known the shared secret.

4. The method of claim 3 , wherein pre-staging is performed in a trusted environment.

5. The method of claim 4 , wherein if pre-staging is not enabled the shared secret is provided secured and encrypted in a configuration update message.

6. The method of claim 1 , further including providing a configuration request from the first termination point to the second termination point subsequent to the calculating step.

7. The method of claim 1 , wherein the discovery request, discovery response, join request, and join response are themselves not encrypted.

8. The method of claim 1 , wherein the shared secret is configured using a command line interface.

9. The method of claim 1 , wherein the control frames are encapsulated using a common header format.

10. A wireless local area network system comprising:

a first termination point communicatively coupled with a second termination point over a wireless local area network, each of the first and second termination points having a shared secret;

wherein the second termination point is configured to receive a discovery request from the first termination point, generate a first nonce, encrypt the first nonce using a master key derived from the shared secret, and transmit the encrypted first nonce to the first termination point in a discovery response;

wherein the first termination point is configured to decrypt the encrypted first nonce using the same master key derived from the shared secret, generate a second nonce, concatenate the first and second nonces, encrypt the concatenated first and second nonces using the master key to form an encrypted join request, and send the encrypted join request to the second termination point;

wherein the second termination point is configured to decrypt the encrypted join request to determine a decrypted first nonce and, if the first nonce is equal to the decrypted first nonce, send a join response to the first termination point indicative of authentication, and calculate a session key from at least one nonce; and

wherein both the first and second termination points are configured to enter a run state and intercommunicate control frames in accordance with the session key.

11. The system of claim 10 , wherein the session key is derived from the shared secret and the first and second nonces such that the session key is unique for the session despite being generated from the same shared secret.

12. The system of claim 10 , wherein if authentication is received and if pre-staging is enabled for the first termination point, the second termination point sends the shared secret without encryption in the join response to the first termination point, wherein sending the shared secret completes mutual authentication of the two termination points by proving that the two termination points both known the shared secret.

13. The system of claim 12 , wherein pre-staging is performed in a trusted environment.

14. The system of claim 13 , wherein if pre-staging is not enabled the shared secret is provided secured and encrypted in a configuration update message.

15. The system of claim 10 , wherein the first termination point is configured to send a configuration request to the second termination point.

16. The system of claim 10 , wherein the discovery request, discovery response, join request, and join response are themselves not encrypted.

17. The system of claim 10 , wherein the shared secret is configured using a command line interface.

18. The system of claim 10 , wherein the control frames are encapsulated using a common header format.

19. An access point configured to securely communicate control frames over a wireless local area network, the access point comprising:

a memory for storing a shared secret and a set of machine-readable instructions;

a processor configured to execute the set of machine-readable instructions to cause the access point to send a discovery request, receive first nonce encrypted using a master key derived from the shared secret, decrypt the encrypted first nonce using the same master key derived from the shared secret, generate a second nonce, concatenate the first and second nonces to form a concatenated result, encrypt the concatenated result using an encryption algorithm and the master key to form an encrypted join request, send the encrypted join request over the wireless local area network, receive a join response indicative of authentication if the first nonce is equal to the decrypted first nonce;

calculate a session key from at least one nonce; and transmit the control frames in accordance with the session key.

Assignments (13)

Continuity (1)