1. Mesh Frame Formats Date: 2007-06-26 Authors: June 2007 March 2007
doc.: IEEE /0550r7
June 2007
Mesh Frame Formats
Date:
Authors:
Guenael Strutt, Motorola et al.
Guenael Strutt, Motorola et al.

2. March 2007
doc.: IEEE /0550r7
June 2007
Abstract
Many comments were raised during LB93 about the definition of new frame format types and subtypes in D This presentation identifies possible resolutions to comments classified under the General identifiers G11.
Ideally, mesh frames should be compatible with frames and features from other task groups, e.g. TGn, TGv, TGw.
This presentation is a summary of 11-07/799r6, which addresses all of the above
Guenael Strutt, Motorola et al.
Guenael Strutt, Motorola et al.

3. Proposed Resolution of General Comments on Frame Formats (11-07/799)
March 2007
doc.: IEEE /0550r7
June 2007
Proposed Resolution of General Comments on Frame Formats (11-07/799)
CIDs in General Category G11:
Need clarification on compatibility of mesh data frame type with existing data subtypes
1672, 2235, 3467, 3601, 4468, 4893
Clarification of extended frame type vs. mesh management frame type vs. using existing frame types
42, 1234, 1582, 2011, 2012, 2013, 2024, 2031, 2055, 2278, 3674, 3675, 3676, 3722, 3723, 3724, 3760, 3761, 3764, 3765, 4470, 4471, 4770
Mesh Management Frame and Mesh Action Data Unit needs clarification
6, 312, 313, 316, 317, 318, 319, 324, 1937, 1939, 2057, 2619, 2900, 3535, 3747,
4018, 4081, 4197, 4894, 4939, 5197
Incomplete frame descriptions
1805, 1936, 3605, 3666
Action encapsulation frame needs clarification
3547
Guenael Strutt, Motorola et al.
Guenael Strutt, Motorola et al.

4. Mesh Management Frames Overview
June 2007
June 2007
Mesh Management Frames Overview
Majority of TGs management frames only require 1-hop transmission
Reuse existing Action Frame subtype (1101) for these frames (defined in Clause 7.4)
Some TGs management frames require multihop transmission
New Multihop Action Frame subtype (1111) includes Mesh Header for these frames (defined in Clause 7.4b)
Allows mesh header insertion as fixed field
Easier hardware decode than IE parsing
Note: management frame subtype 0111 remains reserved for use by other task groups
Slide 4
S. Duvurri, et. al.
Guenael Strutt, Motorola et al.

5. Management Frames for Mesh
March 2007
doc.: IEEE /0550r7
June 2007
Management Frames for Mesh
Action frame
MAC HEADER
PAYLOAD
MGMT 00
ACTION 1101
ADDR1 RA=DA
ADDR2 TA=SA
BSSID 00
CATEGORY X
ACTION Y
Fields/IEs related to this Category/Action
TYPE
SUBTYPE
ACTION FIELD
Path Request Peer Link Open Mesh Channel Switch Link Metric Report Portal Announcement etc.
FIXED LENGTH
MAC HEADER
PAYLOAD
MGMT 00
MH ACTION 1111
ADDR1 RA
ADDR2 TA
ADDR3 DA
Mesh Header
CATEGORY X
ACTION Y
Fields/IEs related to this Category/Action
SUBTYPE
Mesh Header FIELD
ACTION FIELD
Multihop Action frame
Mesh Key Holder Security Establishment PMK-MA Delivery Push etc.
Guenael Strutt, Motorola et al.
Guenael Strutt, Motorola et al.

6. Multihop Action Frame Details
March 2007
doc.: IEEE /0550r7
June 2007
June 2007
Multihop Action Frame Details
MAC HEADER
PAYLOAD
MGMT 00
Multihop Action 1111
ADDR1 RA
ADDR2 TA
ADDR3
Mesh Header
CATEGORYX
ACTION Y
Fields/IEs related to this Category/Action
ACTION FIELD
TYPE
SUBTYPE
Flags
TTL
Seq #
Address Extension
Address Extension Mode
Reserved
Addr4
- OR -
Addr4
Addr5
Addr6 B0 B1
B B7
Applicable for Multihop Action Frames 00
No Mesh Address Extension field 01
Mesh Address Extension field contains Addr4 10
Mesh Address Extension field contains Addr5 and Addr6 11
Mesh Address Extension field contains Addr4, Addr5, and Addr6
Guenael Strutt, Motorola et al. 6
Guenael Strutt, Motorola et al.

7. Mesh Data Frames overview
June 2007
June 2007
Mesh Data Frames overview
Separation from non-mesh device interpretation
Use FromDS = ToDS = 1
Flexibility of broadcast addressing schemes
Addr1 can contain unicast address or multicast address (a separate contribution is being prepared to specify more details here)
Support for loop detection
Mesh header always included
Compatibility with existing cipher suite designs
Security header (IV/extended IV) always appears directly following MAC header
Slide 7
S. Duvurri, et. al.
Guenael Strutt, Motorola et al.

8. Address Extension Mode Applicable for Data Frames
March 2007
Month Year
doc.: IEEE /0550r7
doc.: IEEE yy/xxxxr0
June 2007
Data Frame Format
FrameControl.ToDS = FrameControl.FromDS = 1
MAC HEADER
PAYLOAD
TYPE
SUBTYPE
Data 10
Any
XXXX
ADDR1 RA
ADDR2 TA
ADDR3
ADDR4
Mesh Header
SNAP/LLC…
Flags
TTL
Seq #
Address Extension
Address Extension Mode
Reserved
Addr5
Addr6 B0 B1
B B7
Applicable for Data Frames 00
No Mesh Address Extension field 01
Mesh Address Extension field contains Addr4 10
Mesh Address Extension field contains Addr5 and Addr6 11
Mesh Address Extension field contains Addr4, Addr5, and Addr6
Guenael Strutt, Motorola et al.
Page 8
John Doe, Some Company
Guenael Strutt, Motorola et al.

9. References doc.: IEEE 802.11-07-0023r35 (Issue Identifier G11)
March 2007
doc.: IEEE /0550r7
June 2007
References
doc.: IEEE r35 (Issue Identifier G11)
Guenael Strutt, Motorola et al.
Guenael Strutt, Motorola et al.

10. March 2007
doc.: IEEE /0550r7
June 2007
Data Frames for Mesh
Compatibility with legacy/non-standard implementations
No incompatibilities with legacy BSS/IBSS STA or AP implementations since they use different values for ToDS/FromDS
Some non-standard WDS implementations may automatically attempt to communicate with any nearby device discovered sending 4-address broadcast/multicast data frames (so-called “Lazy WDS” scheme)
MPs ignore 4-address data frames transmitted by legacy/non-standard WDS devices, since they do not establish a mesh link
Guenael Strutt, Motorola et al.
Guenael Strutt, Motorola et al.