The Mesh Function Test Report
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信言不美，美言不信。善者不辯，辯者不善。知者不博，博者不知。聖人不積，既以為人己愈有，既以與人己愈多。天之道，利而不害；聖人之道，為而不爭。 |
1. Background and
definition for Robin mesh scheme
"robin
mesh" is a stand alone system and concerns all
network and transport related topics. Based on OpenWrt kamikaze. B.A.T.M.A.N
detects neighbors and distant nodes by broadcasting, receiving, and rebroadcasting originator messages (OGM)
according to the rules of the B.A.T.M.A.N. algorithm. These OGMs are flooding
through the mesh-cloud until they get lost or nobody has to rebroadcast them
any more. Once a node receives an OGM
message initiated from a distant node it is aware of the existence of the node.
1.1
Definition
gateway node
The node which offers Internet
connectivity is called a gateway node and has to be simply connected to a xDSL
router, or also to a device acting as STA (with no AP) in the way of client
bridge.
client (repeater)
node
A repeater node is simply powered
on and palced in good location forward other nodes. A node receive OGMs by
other nodes actives in the mesh cloud and knows network topology within one or
two minutes; then BATMAN arrange the node routing table in order to discover
the best path to an internet gateway.
Diagram 1-1 gateway node Diagram 1-2 client node
1.2 ROBIN interfaces
node
|
ath0
|
ath2
|
ath1
|
eth0
|
gateway
|
mesh and forward
iface
|
batman WPA-PSK AP
iface - default gateawy for private wlan users
|
batman open AP iface
- default gateawy for pubblic wlan users
|
WAN iface
administratrive tasks on eth0:1
|
client
|
mesh and forward
iface
|
batman WPA-PSK AP
iface - default gateawy for private wlan users
|
br0 (ath1-eth0
bridge)
default gateawy for pub.wlan and wired users
|
node
|
tun iface
(gate0)
|
Gateway and client
|
If a gateway is found batman will create a
tun device and alters the routing table accordingly by setting a default
route. Once you want Internet your traffic will end up in batman which will
than contact the gateway and ask for an IP for the tun interface. The gateway
will send an IP back so that your tun interface has an IP. Your traffic will
be tunnelled to the gateway as long as you need it. At the end your client
will release the IP.
|
2. Getting
access to a node
Getting the first access to a node requires that you login via ssh (on windows you
would need to install something like Putty). We can ssh to a node through, (please see below diagram 2, ssh login by
account root and password 0p3nm35h)
·
gateway node
o wifi
connection using open_AP IP or WPA-PSK_AP IP addresses
o wired
connection to a "free" ethernet port of the DSL Router (if combo) or
via switch which connects DSL router
·
repeater (client) node
o wired
cable or wifi connection using open_AP IP or WPA-PSK_AP IP addresses
Diagram 2 -- ssh login by account root
and password 0p3nm35h
3. Mesh Function Test
The mesh function is adopting from ROBIN mesh
scheme, for our target board AP51 with 8M flash/16MB RAM, added to OpenWrt trunk
code base, surely to play a role of mesh node.
The sources are coming from the open
resource site, thanks to all forum developers.
OpenWrt Revision: kamikaze_trunk, or
equivalent to Kamikaze 8.x
ROBIN Mesh Revision: beta-1.21.11
OpenWrt:
svn co
https://svn.openwrt.org/openwrt/packages packages
ROBIN Mesh:
svn co
https://svn2.hosted-projects.com/ansanto/robin/openwrt/kamikaze_8/packages/robin-mesh
robin-mesh
3.1 Nodes Deployment -- serial chaining placement
number
|
Node
|
Mesh IP addr
|
MAC id
|
|
1
|
Gateway
|
5.33.192.154
|
00:12:cf:21:c0:9b
|
Internet
connectivity
|
2
|
Client 1
|
5.131.126.160
|
00:12:cf:83:7e:a1
|
Forward other
nodes
|
3
|
Client 2
|
5.28.131.152
|
00:18:84:1c:83:99
|
Forward other
nodes
|
The customer’s firmware is a reference
sample. So, I do two experiments, the first one is using customer’s one as
reference. And the version I built (i.e. accton built version) is our main goal
of experiment to practice. The test network
diagram, please see below diagram 3.
Diagram 3 -- The AP 51 mesh function test network
3.2 Test considerations – choose a better WIFI
bit rate at Taichung
office area
The distance is away from 1.18 m between two nodes at various bit rate.
Bit rate
|
5.5
|
11
|
12
|
18
|
24
|
36
|
48
|
54
|
Throughput(avg)
|
2.35
|
3.35
|
3.19
|
3.20
|
3.12
|
3.19
|
3.21
|
3.38
|
The distance is away from 10.5 m
between two nodes at various bit rate.
Bit rate
|
5.5
|
11
|
12
|
18
|
24
|
36
|
48
|
54
|
Throughput(avg)
|
2.32
|
3.4
|
3.1
|
2.6
|
2.46
|
2.5
|
2.57
|
2.6
|
So, I judge to use 11Mbps as bit rate for wifi
radio 11g mode, and turn off
the traffic control function for the mesh function, the testings are performed at
the rate of 11 Mbps of this choice.
3.3
Test result
The test case is using Chariot TCP end-to-end
throughput script.
The wifi 11g mode bit rate is set to 11Mbps.
Disable the traffic control
The background noise and interference is also existing.
End-to-end throughput
Taichung Office (12F)
|
Average
Mbps
|
Max
Mbps
|
Min
Mbps
|
Distance
|
Topology
Changed
|
Client
1 to gateway node
|
3.431
|
4.082
|
1.684
|
One
hop(10.56m)
|
Y
|
Client
2 To Gateway node
|
2.617
|
3.941
|
1.156
|
Two
hops(12.54m)
|
Y
|
Table 3-1 -- The action-built-version test result summary (office
area,12F)
End-to-end throughput
Taichung Baseroom(B2)
|
Average
Mbps
|
Max
Mbps
|
Min
Mbps
|
Distance
|
Topology
Changed
|
Client 1 to gateway node
|
3.955
|
4.145
|
3.320
|
One
hop(17.25m)
|
Y
|
Client 2 To Gateway node
|
3.639
|
4.324
|
1.001
|
Two
hops(12.75m)
|
Y
|
Table 3-2 – The action-built-version test result summary (baseroom,
B2)
Compressed image
|
Original
raw version
|
Version
With Mesh
|
Kernel
|
768KB
|
768KB
|
Root file system
|
1280KB
|
2560KB
|
Table 3-3 -- The action-built-version Size
changed with compression
4. The result of Accton built firmware
The test settings on AP51 mesh function
test are set up as below,
(a)The wifi 11g mode bit rate is set to 11Mbps.
(b) Disable the traffic control
(c)The test case is using
1. Chariot TCP end-to-end throughput script.
2.
Iperf
(d)The test field is at Taichung office area(12 Floor), and
baseroom(B2), respectively.
4.1. One hop
end-to-end throughput measurement
The data is generated by iperf (see diagram
4-1-1). Meanwhile, we watch
on the batman packets activities, by using command “batman –c –d 1” and “batman –c –d 4” on the console command line(see diagram
4-1-2, 4-1-3). And after then, we use chariot to measure the
throughput (see diagram 4-1-4).
Diagram 4-1-1: Iperf bandwidth monitoring
Diagram
4-1-2 hops forwarding
Diagram
4-1-3 neighbors
Diagram 4-1-4 chariot throughput
4.2. Two hops end-to-end measurement(Office
area, 12F)
The data is generated by iperf (see diagram
4-2-1). Meanwhile, we watch on the batman packets activities, by
use command “batman –c –d 1”
and “batman –c –d 4” on the
console command line (see diagram 4-2-2, diagram
4-2-3). And then, we use chariot to measure the throughput(see diagram
4-2-4).
Diagram 4-2-1 iperf bandwidth
monitoring
Diagram 4-2-2 hops forwarding
Diagram 4-2-3 neighbor
Diagram 4-2-4 chariot throughput
4.3 Remove the
middle hop
Remove middle way
hop, then add it again after 3 minutes.
1. To see from hop to hop activities
2. To see how fast the changes when recover
the throughput if remove the middle hop. Shown as diagram 4-3-1.
Diagram
4-3-1 Remove the middle hop
4.4 Topology
changed
We can use command
“batman –c –d 1” or “batman
–c –d 2”, or
“batman –c –d 4”, to see
detailed packet forwarding and mesh topology changed.
4.5 The test
result in baseroom (B2)
4.5.1. One hop end-to-end throughput measurement
4.5.1. Two hop end-to-end throughput measurement
