Continuous authorization monitoring

1. A security system, comprising:

a first security badge having a visual portion that varies according to signals provided to the first security badge; and

an authorization server that provides the signals to the first security badge in response to periodic queries of the authorization server by the first security badge while the first security badge remains in a controlled zone;

wherein the controlled zone is defined by one or more badge readers controlling initial access to the controlled zone; and

wherein the periodic queries by the first security badge and the corresponding responsive signals from the authorization server are independent of any of the one or more badge readers accessing the first security badge.

2. A security system, according to claim 1 , wherein the first security badge is read by any of the one or more badge readers only in connection with initial entry into the controlled zone.

3. A security system, according to claim 1 , wherein authorization of a user of the first security badge varies while the user remains in the controlled zone.

4. A security system, according to claim 1 , wherein the first security badge includes a visual image of the user of the first security badge and displays additional information.

5. A security system, according to claim 4 , wherein the additional information includes name and authorization status of the user.

6. A security system, according to claim 5 , wherein the authorization status of the user is indicated by at least one of: a watermark superimposed on the image of the user, a word or phrase dynamically provided on the first security badge, dimming the image of the user, dimming the first security badge, a strikethrough superimposed on the image of the user, an LED provided on the first security badge, or a background color of the first security badge.

7. A security system, according to claim 5 , wherein the authorization status of the user is indicated by a sound provided by the first security badge.

8. A security system, according to claim 1 , wherein the first security badge queries the authorization server using a smartphone that is in communication with the first security badge and with the authorization server.

9. A security system, according to claim 1 , wherein the queries from the first security badge to the authorization server include location information indicating a location of the first security badge.

10. A security system, according to claim 9 , wherein the authorization server uses the location information to determine authorization for the first security badge.

11. A security system, according to claim 1 , further comprising:

a second security badge provided in the controlled zone.

12. A security system, according to claim 11 , wherein the first security badge indicates authorization status of the second security badge.

13. A security system, according to claim 11 , wherein the second security badge queries the first security badge for authorization status of the second security badge.

14. A method of operating a security system, comprising:

providing a first security badge having a visual portion that varies according to signals provided to the first security badge;

the first security badge periodically querying an authorization server while the first security badge remains in a controlled zone, wherein the controlled zone is defined by one or more badge readers controlling initial access to the controlled zone; and

the authorization server providing the signals to the first security badge responsive to the periodic queries;

wherein the periodic queries by the first security badge and the corresponding responsive signals from the authorization server are independent of any of the one or more badge readers accessing the first security badge.

15. A method, according to claim 14 , wherein the first security badge is read by any of the one or more badge readers only in connection with initial entry into the controlled zone.

16. A method, according to claim 14 , wherein authorization of a user of the first security badge varies while the user remains in the controlled zone.

17. A method, according to claim 14 , wherein the first security badge includes a visual image of the user of the first security badge and displays additional information.

18. A method, according to claim 17 , wherein the additional information includes name and authorization status of the user.

19. A method, according to claim 18 , wherein the authorization status of the user is indicated by at least one of: a watermark superimposed on the image of the user, a word or phrase dynamically provided on the first security badge, dimming the image of the user, dimming the first security badge, a strikethrough superimposed on the image of the user, an LED provided on the first security badge, or a background color of the first security badge.

20. A non-transitory computer readable medium containing software that operates a security system, the software comprising executable code that implements the method of:

varying a visual portion of a first security badge according to signals provided to the first security badge;

periodically querying an authorization server by the first security badge while the first security badge remains in a controlled zone, wherein the controlled zone is defined by one or more badge readers controlling initial access to the controlled zone; and

providing the signals to the first security badge from the authorization server responsive to the periodic queries;

wherein the periodic queries by the first security badge and the corresponding responsive signals from the authorization server are independent of any of the one or more badge readers accessing the first security badge.