Transcript Two-tier Dynamic Load Balancing with SDN

Two-tier Dynamic Load Balancing with SDN
Check points of Implementation:
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Communication
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Calculation
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In Controller
Detection
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Between Controller and Devices
In devices
Two-tier Dynamic Load Balancing with SDN
Communication:
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Wi-Fi Device
Ryu Controller
Switch Enter
Calculation
Switch
Features
Switch
Experimenter
Packet In
Switch Leave
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1. TCP socket
Boot up/
Report info.
2.SwitchFeature
3. Experimenter Msg
Update info.
Shutdown/
Crash/ Kill ps.
Detection
Two-tier Dynamic Load Balancing with SDN
Communication logs:
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switchEnter, switchLeave, switchFeatures, switchExperimenter:
Two-tier Dynamic Load Balancing with SDN
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Packet_In log in device:
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Packet_In log in Controller:
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Two-tier Dynamic Load Balancing with SDN
PACKET_IN message type:
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dp_control.c
Create packet
Two-tier Dynamic Load Balancing with SDN
PACKET_IN message type:
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Assign message data:
Two-tier Dynamic Load Balancing with SDN
Calculation:
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New AP joins network
New Station joins network
AP leaves network
Balanced: Controller makes decision
i 
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 na i  ns i , j

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* max load
M

 j 1  i , j

 
i, j


na i
 ns i , j

na i *  
* max load
M
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j 1 
i, j

2



i, j

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2


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 na i  ns i , j
* max load
 
M
 j 1  i , j
Li  
na i




 
i, j





Two-tier Dynamic Load Balancing with SDN
Init phase:
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Calculation
1. TCP socket
Switch
Features
2.SwitchFeature
Switch
Experimenter 3. Experimenter msg.
Monitor phase:
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Calculation
2. Packet_in
Packet In
3. datapath.send_msg with Experimenter
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Boot up/
Report info./
Listen Exp.
1. Changed
Update info.
Listen Exp.
Action/ Apply
Detection
Two-tier Dynamic Load Balancing with SDN
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Two-tier Dynamic Load Balancing with SDN
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Two-tier Dynamic Load Balancing with SDN
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The todo list of Detection:
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Monitor:
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Pthread_create: done
Get the real information of device: partial done
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Report/Update: done
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isChanged and PACKET_IN
Decision (Action/ Apply): progressing
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TxPower apply:
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iw dev <devname> set txpower <auto|fixed|limit> [<tx power in mBm>]
Under loaded: no need to change
Over loaded: disassociate station command
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Max_conn, SNR, PER need to calculate
hostapd_cli deauthenticate <STA_MAC>
hostapd_cli disassociate <STA_MAC>
Balanced: report association table to controller
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iwinfo wlan0 assoclist
Two-tier Dynamic Load Balancing with SDN
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The data structures of device information:
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Two-tier Dynamic Load Balancing with SDN
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Show and configuration of device:
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OpenWRT (AP222)
UCI system
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uci show wireless
uci set wireless.xxx=yyy; uci commit wireless
Cat /etc/config/wireless
iw commands
iwinfo commands
hostapd_cli commands
Two-tier Dynamic Load Balancing with SDN
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Critical
section:
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Two-tier Dynamic Load Balancing with SDN
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Unit test plan (1/3):
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Controller
New AP:
High
loading:
CPU, MEM,
PER(?)
Lower
Signal
strength
Controller
AP-1
New
AP
AP-1
STA-1
STA-2
After add the new AP
STA-1
STA-2
Initialize the topology
Stable time:
1) Start time:
New AP gets the SwitchFeature from controller
2) End time:
New AP detects the changed when station
connected
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Two-tier Dynamic Load Balancing with SDN
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Unit test plan (2/3):
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New Station:
Higher
Signal
strength
Controller
AP-1
AP-2
Higher
Signal
strength
Controller
AP-1
STA-1
AP-2
New
station
After add the new Station
STA-1
Initialize the topology
Stable time:
1) Start time:
AP detects the station’s request of link layer
association
2) End time:
New station pings out successfully (?)
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Two-tier Dynamic Load Balancing with SDN
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Unit test plan (3/3):
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Remove AP:
Higher
Signal
strength
Controller
AP-1
STA-1
Higher
Signal
strength
Controller
AP-1
AP-2
AP-3
STA-2
Initialize the topology
STA-1
AP-2
STA-2
After remove the AP-3
Stable time:
1) Start time:
STA-2 fails to ping out (?)
2) End time:
STA-2 pings out successfully (?)
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AP-3
Two-tier Dynamic Load Balancing with SDN
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Simulation unit testing (1/4):
Controller
AP-1
Advantages:
1. Communication with OpenFlow
protocol
2. Don’t need more devices
3. The meter function can locate in the
device.
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Steps:
1. AP-1 reports multiple
packet_in with fake MAC to
controller
2. AP-1 reports its information
with fake connection number
3. AP-1 applys the decision from
controller
Two-tier Dynamic Load Balancing with SDN
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Simulation unit testing (2/4):
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Fake MAC from one AP:
Two-tier Dynamic Load Balancing with SDN
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Simulation unit testing (3/4):
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Fake stations from one AP:
AP reports the association table
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Two-tier Dynamic Load Balancing with SDN
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Simulation unit testing (4/4):
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AP receives the decision from controller:
Two-tier Dynamic Load Balancing with SDN
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Issues:
 Crash after several packet_in:
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AP222 can not assign dhcp ip to station
Openflow does not support pthread : resolved
Device inform controller with PACKET_IN: done
The issues when using the debug message in Openflow switch:
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[X] OFP_FATAL(0, “xxxx….");
[X] ofp_error ( retval, “zzz……”);
[O] VLOG_WARN_RL(LOG_MODULE, &rl, “yyyy…..”);
Reference
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http://tocai.dia.uniroma3.it/compunetwiki/index.php/Installing_and_setting_up_OpenFlow_tools
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https://github.com/CPqD/ofsoftswitch13
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https://github.com/CPqD/ofsoftswitch13/wiki/OpenFlow-1.3-Tutorial
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