1. Enhancement to Mesh Discovery
Month Year
doc.: IEEE yy/xxxxr0
March 2008
Enhancement to Mesh Discovery
Date:
Authors:
Michelle Gong, Intel, et al
John Doe, Some Company

2. Outline Enhancement 1: Enhancement 2:
March 2008
Outline
Enhancement 1:
Problem: Individual mesh devices in the same mesh network need to be differentiated
Solution: Utilize a user friendly name, i.e. Mesh Point ID
Enhancement 2:
Problem: An MP needs to discover multiple neighbor MPs and the discovery process can be slow
Solution: Utilize a Mesh Neighbor Report process
Michelle Gong, Intel, et al

3. A mesh ID identifies a mesh network but not individual mesh points
March 2008
A mesh ID identifies a mesh network but not individual mesh points
Users of infrastructure networks just want to connect to a network that offers internet connection
An SSID is sufficient to identify such a network
However, users of a mesh network may want to identify different MPs within the same network
For municipal mesh networks, service providers may want to identify individual mesh points for network maintenance and diagnostic purposes
In home mesh networks, different mesh devices have different functionalities and offer different services. It may not be necessary to set up peer links with all neighboring devices
Michelle Gong, Intel, et al

4. March 2008
For diagnosis purposes, mesh point IDs can help to identify different mesh devices
For instance, if a user cannot find a particular mesh point or the routes are not what he/she has expected, he/she may want to take a look at the topology
Each MP reports its neighbors and the routes, expressed in MAC addresses
It’s very time consuming to match an MP’s MAC address with the actual physical device in the field
Michelle Gong, Intel, et al

5. March 2008
MP IDs can also be very useful for on-demand peer link set up in home mesh networks
The intent of this proposal is not to replace any higher layer discovery protocol (It’s not a cross-layer solution. Higher layer discovery protocols will still be used.)
Instead, we’d like to provide a layer-2 solution to facilitate on-demand peer link set up for small form factor devices, such as PDAs or cell phones
Other optimization solutions are also possible if the “Printer” is more than one-hop away
PDA
Printer
Michelle Gong, Intel, et al

6. March 2008
Just as a route can be set up on-demand, some devices may want to set up peer links on-demand
Small form factor devices, such as PDAs and cell phones, want to consume as little energy as possible
Setting up and maintaining peer links with all neighbors can be expensive in terms of computation, resource consumption, and energy consumption
One optimization is to allow an MP to only set up peer links with the devices that it will use
For instance, it can be a user configurable option: 1) on-demand peer link set up; 2) automatic peer link set up
Michelle Gong, Intel, et al

7. A mesh point ID is a name that a user gives to a mesh point
March 2008
A mesh point ID is a name that a user gives to a mesh point
A student, Mike, may have a mesh network that consists of 5 mesh points
Without the MP ID, Mike can only see the mesh ID, i.e. “Mike’ Mesh”
Because Mesh IDs are included in beacons/probe responses, Mike will be able to see them before his devices set up peer links with any of the MPs
If Mike is a smart student majoring in computer networks, he may choose to look at individual MPs’ MAC address to differentiate MPs
Mike’s Mesh
Mike’s Mesh (…….)
Mike’s Mesh (00-0F-47-6E-39-F3)
Mike’s Mesh (00-0E-35-8F-C3-D9)
Mesh ID & MAC Address
Mesh ID only
Michelle Gong, Intel, et al

8. March 2008
Mesh point IDs are much easier to remember and recognize than MAC addresses
With the MP ID, Mike can see the following structure:
Mike can recognize the printer and select it for printing without having to remember its MAC address
We propose to put the MP ID in the Peer Link Setup message
Mike’s Mesh
Ingree (or IBM laptop)
Harry (or HP printer)
Danny (or Dell desktop)
Mary (or Monitor)
Susan (or Sony DVD player)
City’s mesh
4th & Philadelphia
3rd & Florida
2nd & Virginia
5th & Massachusetts
1st & Washington
Mesh ID & Mesh Point ID
To distinguish mesh ID and mesh point ID, we can call Mesh ID as Mesh Network ID
Michelle Gong, Intel, et al

9. The format of MP ID is the same as that of the mesh ID or SSID
March 2008
The format of MP ID is the same as that of the mesh ID or SSID
BSSID is used to identify each BSS in an infrastructure network. Yet, BSSID is a 6-octect MAC address, which is not easily recognized by human users
A mesh point ID is intended to be a name that can be easily remembered and recognized by a human user
A variable length MP ID field, i.e. 0 to 32-octet, indicates the identity of the MP
Element ID
Length
Mesh Point ID 1
0-32
Michelle Gong, Intel, et al

10. Outline Enhancement 1: Enhancement 2:
March 2008
Outline
Enhancement 1:
Problem: Individual mesh devices in the same mesh network need to be differentiated
Solution: Utilize a Mesh Point ID
Enhancement 2:
Problem: An MP needs to discover multiple neighbor MPs and the discovery process can be slow
Solution: Utilize a Mesh Neighbor Report process
Michelle Gong, Intel, et al

11. March 2008
As currently defined in 11s, an MP needs to scan and discover its neighboring MPs autonomously
In an infrastructure network, a STA only needs to discover and associate to one AP (Not a problem)
In a mesh network, a MP may want to set up peer links with multiple MPs
Given that different MPs might be on different channels and some of them may be in power save mode, a complete discovery process in a mesh network can be much slower than that in an infrastructure network
We propose to use a Mesh Neighbor Report to speed up the discovery process
Similar concept exists for the infrastructure mode of operation
Details are different
Michelle Gong, Intel, et al

12. Mesh Neighbor Report Request
March 2008
A new MP can discover more neighbors through a mesh neighbor report request/response frame exchange
Mesh Neighbor Report Request
Mesh Neighbor Report Response
Category
Dialogue token
Action
Optional elements
Optional elements may include Mesh ID, Mesh Point ID, etc.
Category
Dialogue token
Action
MP report element
Michelle Gong, Intel, et al

13. Optional subelements may include TSF information, etc.
March 2008
The Mesh Neighbor Report element contains discovery-related information of neighboring MPs
Existing MP reports neighbor MPs’ addresses, information, channel, PHY type, and optional sub-elements
Element ID
MP address
Length
MP information
Regulatory class
Channel number
PHY type
Optional subelements 1 4 6
variable
octets:
Optional subelements may include TSF information, etc.
Security bits
Information 00
Security information unknown 01
Reserved 10
Different security provisioning 11
Same security provisioning
security
capabilities
Reserved
Bits: 14 16 2
MP Information
The security bits indicate whether the neighbor MP supports the same security provisioning as the MP sending the report
Michelle Gong, Intel, et al

14. Synchronization enabled
March 2008
The capability field contains selected capability information of the neighbor MP
The selected capability information identifies the basic information of a neighbor MP
Accept peer links
Power Save enabled
Synchronization enabled
Bits: 2
MDA enabled
For-warding
HT support
Power Save active
Capability bits
Information 00
Information unknown 01
Reserved 10
Not supported 11
Supported
Michelle Gong, Intel, et al

15. More details on how to set the capability bits
March 2008
More details on how to set the capability bits
The “Accepting Peer Links” field is set to 11 if the MP is able and willing to establish peer links with other MPs
The “Synchronization Enabled” field is set to 11 if the MP is capable to synchronize with peer MPs
The “Power Save Enabled” field is set to 11 if the MP is capable to go into power save mode
The “Power Save Active” field is set to 11 if the MP is currently in power save mode
The “MDA Enabled” field is set to 11 if the MP supports MDA services
The "Forwarding" field is set to 11 if the MP is a forwarding MP
The “HT support” field is set to 11 if the MP supports high throughput
Michelle Gong, Intel, et al

16. March 2008
In summary, we propose two mesh discovery enhancement schemes: 1) a mesh point ID and 2) mesh neighbor report
Using Mesh Point IDs, user friendly names can be given to individual mesh points
Facilitate on-demand peer-link set up, which reduces the number of peer links an MP has to maintain (saves energy and computation; reduces broadcast traffic)
Help users to debug mesh networks more efficiently
The Mesh Point ID can be included in the Peer Link Setup message
Mesh neighbor report can be utilized for faster mesh discovery
After setting up a peer link with one MP, a new MP can discover multiple neighbor MPs through the neighbor MP report
Add one bit to the mesh capability field:
The bit “Mesh Neighbor Report supported” is set to the value of dot11MeshNeighborReportEnabled
Michelle Gong, Intel, et al