LONG RANGE WLAN DATA UNIT FORMAT

• US 20130044877A1
• Filed: 08/15/2012
• Published: 02/21/2013
• Est. Priority Date: 08/15/2011
• Status: Active Grant

• Current Assignee: Marvell Asia Pte Limited (Marvell Technology Group Limited)
• Original Assignee: Marvell International Limited (Marvell Technology Group Limited)
• Inventors: Liu, Yong, Ramamurthy, Harish, Zhang, Hongyuan
• Granted Patent: US 9,083,590 B2
• Time in Patent Office: Days
• US Class Current: 380/270
• CPC Class Codes: H04L 27/0006 Assessment of spectral gaps suitable for allocating digitally modulated signals, e.g. for carrier allocation in cognitive radio for spectrum sharing between different networks H04W16/14
• CPC Class Codes: H04L 27/2602 Signal structure
• CPC Class Codes: H04L 27/2613 Structure of the reference signals
• CPC Class Codes: H04L 27/26136 Pilot sequence conveying additional information
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04L 5/0091 Signaling for the administration of the divided path
• CPC Class Codes: H04W 28/06 Optimizing the usage of the radio link, e.g. header compression, information sizing , discarding information system modifying transmission characteristic according to link quality by modifying frame length H04L1/0007; dynamic adaptation of the packet size for flow control or congestion control H04L47/365
• CPC Class Codes: H04W 72/54 based on quality criteria
• CPC Class Codes: H04W 8/26 Network addressing or numbering for mobility support
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

In a method for generating a data unit for transmission in a wireless network, a physical layer (PHY) preamble is generated. In generating the PHY preamble, a first indicator is generated to indicate at least one of (i) whether the data unit includes data offloaded from a mobile telephony network separate from the wireless network, or (ii) whether the data unit (a) was generated by, or (b) is addressed to, a communication device that supports offloading of data from the mobile telephony network to the wireless network. The first indicator is included in the PHY preamble. Additionally, a media access control layer (MAC) header is generated. The data unit is generated to include the PHY preamble and the MAC header. The data unit is then caused to be transmitted.

Claims

1. A method for generating a data unit for transmission in a wireless network, the method comprising:

generating a physical layer (PHY) preamble, including;

generating a first indicator to indicate at least one of (i) whether the data unit includes data offloaded from a mobile telephony network separate from the wireless network, or (ii) whether the data unit (a) was generated by, or (b) is addressed to, a communication device that supports offloading of data from the mobile telephony network to the wireless network,

including the first indicator in the PHY preamble;

generating a media access control layer (MAC) header;

generating the data unit to include the PHY preamble and the MAC header; and

causing the data unit to be transmitted.

2. A method according to claim 1, wherein the first indicator also indicates whether the data unit is addressed to a power constrained communication device in the wireless network.

3. A method according to claim 1, wherein generating the PHY preamble further includes:

generating a second indicator to indicate whether the data unit is addressed to a power constrained communication device in the wireless network; and

including the second indicator in the PHY preamble.

4. A method according to claim 1, wherein generating the PHY preamble further includes:

generating an address field to include at least a partial address of a communication device to which the data unit is intended; and

including the address field in the PHY preamble.

5. A method according to claim 4, wherein the first indicator is part of the address field.

6. A method according to claim 4, wherein the first indicator is a field separate from the address field.

7. A method according to claim 1, wherein generating the PHY preamble further includes:

generating a second indicator to indicate whether the data unit is transmitted by an access point; and

including the second indicator in the PHY preamble.

8. A method according to claim 1, wherein generating the PHY preamble further includes:

generating a network identifier (ID) field; and

including the network ID field in the PHY preamble.

9. An apparatus, comprising:

a network interface configured to;

generate a physical layer (PHY) preamble of a data unit at least by generating a first indicator to indicate at least one of (i) whether the data unit includes data offloaded from a mobile telephony network separate from the wireless network, or (ii) whether the data unit (a) was generated by, or (b) is addressed to, a communication device that supports offloading of data from the mobile telephony network to the wireless network, and

including the first indicator in the PHY preamble;

generate a media access control layer (MAC) header; and

generate the data unit to include the PHY preamble and the MAC header;

transmit the data unit.

10. An apparatus according to claim 9, wherein the first indicator also indicates whether the data unit is addressed to a power constrained communication device in the wireless network.

11. An apparatus according to claim 9, wherein the network interface is also configured to

generate a second indicator to indicate whether the data unit is addressed to a power constrained communication device in the wireless network, and

include the second indicator in the PHY preamble.

12. An apparatus according to claim 9, wherein the network interface is also configured to

generate an address field to include at least a partial address of a communication device to which the data unit is intended, and

include the address field in the PHY preamble.

13. An apparatus according to claim 12, wherein the first indicator is part of the address field.

14. An apparatus according to claim 12, wherein the first indicator is a field separate from the address field.

15. An apparatus according to claim 9, wherein the network interface is also configured to

generate a second indicator to indicate whether the data unit is transmitted by an access point, and

include the second indicator in the PHY preamble.

16. An apparatus according to claim 9, wherein the network interface is also configured to

generate a network identifier (ID) field, and

include the network ID field in the PHY preamble.

17. A method for generating a data unit for transmission in a wireless network, the method comprising:

generating a physical layer (PHY) preamble;

generating a media access control layer (MAC) header;

generating a cryptography information header to include information for decrypting an encrypted data portion, wherein a length of the cryptography information header is at most four bytes;

generating the encrypted data portion;

generating the data unit to include (i) the PHY preamble, (ii) the MAC header, (iii) the cryptography information header, and (iv) the encrypted data portion; and

causing the data unit to be transmitted.

18. A method according to claim 17, wherein the length of the cryptography information header is at most two bytes.

19. A method according to claim 17, wherein the MAC header is generated to include an indicator of a key to be used for decrypting the encrypted data portion.

20. A method according to claim 17, wherein generating the MAC header comprises generating the MAC header to include at least one of (i) a network identifier (ID), and (ii) an association ID having a maximum length of 12 bits, the association ID indicating a transmitter of the data unit;

wherein generating the encrypted data portion comprises;

generating a nonce to include at least one of (i) the network ID and (ii) the association ID;

using the nonce to encrypt the data portion.

21. A method according to claim 17, wherein generating the PHY preamble or generating the MAC header comprises generating the PHY preamble or the MAC header to include a flag that indicates whether the data unit is transmitted from an access point:

wherein generating the encrypted data portion comprises;

generating a nonce to include the flag; and

using the nonce to encrypt the data portion.

22. A method according to claim 17, wherein generating the encrypted data portion comprises:

generating a nonce to include a media access control (MAC) address of an intended recipient of the data unit, wherein the MAC address is included in the MAC header; and

using the nonce to encrypt the data portion.

23. A communication device, comprising:

a network interface configured to

generate a physical layer (PHY) preamble;

generate a media access control layer (MAC) header;

generate a cryptography information header to include information for decrypting an encrypted data portion, wherein a length of the cryptography information header is at most four bytes;

generate the encrypted data portion;

generate the data unit to include (i) the PHY preamble, (ii) the MAC header, (iii) the cryptography information header, and (iv) the encrypted data portion; and

transmit the data unit.

24. A communication device according to claim 23, wherein the length of the cryptography information header is at most two bytes.

25. A communication device according to claim 23, wherein the network interface is configured to generate the MAC header to include an indicator of a key to be used for decrypting the encrypted data portion.

26. A communication device according to claim 23, wherein the network interface is configured to:

generate the MAC header to include at least one of (i) a network identifier (ID), and (ii) an association ID having a maximum length of 12 bits, the association ID indicating a transmitter of the data unit;

generate a nonce to include at least one of (i) the network ID and (ii) the association ID; and

use the nonce to encrypt the data portion.

27. A communication device according to claim 23, wherein the network interface is configured to:

generate the PHY preamble or the MAC header to include a flag that indicates whether the data unit is transmitted from an access point;

generate a nonce to include the flag; and

use the nonce to encrypt the data portion.

28. A communication device according to claim 23, wherein the network interface is configured to:

generate a nonce to include a media access control (MAC) address of an intended recipient of the data unit, wherein the MAC address is included in the MAC header; and

use the nonce to encrypt the data portion.