Imparting cryptographic information in network communications

1. A method comprising:

receiving cryptographic information inserted into a pre-defined portion of a network communication in a client-server environment, wherein the pre-defined portion of the network communication is reserved for random data to support bandwidth detection;

identifying a location of the cryptographic information in the pre-defined portion of the network communication;

processing the cryptographic information; and

modifying interactions in the client-server environment based at least in part on a result of the processing of the cryptographic information;

wherein the random data is different from the cryptographic information.

2. The method of claim 1 , wherein identifying the location comprises using at least part of the network communication to determine the location.

3. The method of claim 2 , wherein the pre-defined portion includes the random data, and using at least part of the network communication to determine the location comprises:

retrieving a portion of the random data; and

determining an index into the pre-defined portion of the network communication based on the retrieved portion of the random data.

4. The method of claim 3 , wherein using at least part of the network communication to determine the location comprises:

retrieving multiple different portions of the random data; and

determining multiple different indices into the pre-defined portion of the network communication based on the different portions of the random data.

5. The method of claim 1 , wherein processing the cryptographic information comprises establishing a cryptographic key, and wherein modifying interactions in the client-server environment comprises initiating an encrypted session using the cryptographic key.

6. The method of claim 1 , wherein processing the cryptographic information comprises authenticating the network communication, and wherein modifying interactions in the client-server environment comprises turning on or off a feature of a program operating in the client-server environment.

7. A non-transitory computer-readable medium having a computer program product encoded therein, the computer program product operable to cause data processing apparatus to perform operations comprising:

receiving cryptographic information inserted into a pre-defined portion of a network communication in a client-server environment, wherein the pre-defined portion of the network communication is reserved for random data to support bandwidth detection;

identifying a location of the cryptographic information in the pre-defined portion of the network communication;

processing the cryptographic information; and

modifying interactions in the client-server environment based at least in part on a result of the processing of the cryptographic information;

wherein the random data is different from the cryptographic information.

8. The non-transitory computer-readable medium of claim 7 , wherein identifying the location comprises using at least part of the network communication to determine the location.

9. The non-transitory computer-readable medium of claim 8 , wherein the pre-defined portion includes the random data, and using at least part of the network communication to determine the location comprises:

retrieving a portion of the random data; and

determining an index into the pre-defined portion of the network communication based on the retrieved portion of the random data.

10. The non-transitory computer-readable medium of claim 9 , wherein using at least part of the network communication to determine the location comprises:

retrieving multiple different portions of the random data; and

determining multiple different indices into the pre-defined portion of the network communication based on the different portions of the random data.

11. The non-transitory computer-readable medium of claim 7 , wherein processing the cryptographic information comprises establishing a cryptographic key, and wherein modifying interactions in the client-server environment comprises initiating an encrypted session using the cryptographic key.

12. The non-transitory computer-readable medium of claim 7 , wherein processing the cryptographic information comprises authenticating the network communication, and wherein modifying interactions in the client-server environment comprises turning on or off a feature of a program operating in the client-server environment.

13. A system comprising:

a server computer programmed to establish both non-encrypted sessions and encrypted sessions over a network, with client computers, using a session startup handshake including a network communication including a pre-defined portion reserved for random data to support bandwidth detection;

a first of the client computers programmed to establish non-encrypted sessions with the server computer using the session startup handshake; and

a second of the client computers programmed to establish encrypted sessions with the server computer using the session startup handshake including cryptographic information inserted into the pre-defined portion of the network communication;

wherein the server computer and the second client computer are programmed to perform operations comprising: identifying a location of the cryptographic information in the pre-defined portion of the network communication, processing the cryptographic information, and modifying interactions between the server computer and the second client computer based at least in part on a result of the processing of the cryptographic information;

wherein the random data is different from the cryptographic information.

14. The system of claim 13 , wherein the client computers comprise mobile devices.

15. The system of claim 13 , wherein identifying the location comprises using at least part of the network communication to determine the location.

16. The system of claim 15 , wherein the pre-defined portion includes the random data, and using at least part of the network communication to determine the location comprises:

retrieving a portion of the random data; and

determining an index into the pre-defined portion of the network communication based on the retrieved portion of the random data.

17. The system of claim 16 , wherein using at least part of the network communication to determine the location comprises:

retrieving multiple different portions of the random data; and

determining multiple different indices into the pre-defined portion of the network communication based on the different portions of the random data.

18. The system of claim 13 , wherein processing the cryptographic information comprises:

authenticating the network communication, and

establishing a cryptographic key; and

wherein modifying interactions between the server computer and the second client computer comprises:

turning on or off a feature of a program operating in the server computer or the second client computer, and

initiating an encrypted session between the server computer and the second client computer using the cryptographic key.

19. The system of claim 13 , wherein the server computer and the second client computer are programmed to perform the operations comprising: inserting a message authentication code and encryption key establishment information into the network communication.

20. A method comprising:

identifying a location in a pre-defined portion of a network communication to be sent in a client-server environment, wherein the pre-defined portion of the network communication is reserved for random data to support bandwidth detection;

inserting cryptographic information into the pre-defined portion of the network communication at the location; and

sending the network communication in the client-server environment to facilitate modifying interactions in the client-server environment based at least in part on a result of processing of the cryptographic information;

wherein the random data is different from the cryptographic information.

21. The method of claim 20 , wherein the pre-defined portion includes the random data, and identifying the location comprises:

retrieving a portion of the random data; and

determining an index into the pre-defined portion of the network communication based on the retrieved portion of the random data.

22. A non-transitory computer-readable medium having a computer program product encoded therein, the computer program product operable to cause data processing apparatus to perform operations comprising:

identifying a location in a pre-defined portion of a network communication to be sent in a client-server environment, wherein the pre-defined portion of the network communication is reserved for random data to support bandwidth detection;

inserting cryptographic information into the pre-defined portion of the network communication at the location; and

sending the network communication in the client-server environment to facilitate modifying interactions in the client-server environment based at least in part on a result of processing of the cryptographic information;

wherein the random data is different from the cryptographic information.

23. The non-transitory computer-readable medium of claim 22 , wherein the pre-defined portion includes the random data, and identifying the location comprises:

retrieving a portion of the random data; and

determining an index into the pre-defined portion of the network communication based on the retrieved portion of the random data.