Dynamic Load Balance Algorithm (DLBA) forIEEE 80211 Wireless LAN

Presented byKLekhya Ramya Sagarika09MEJU0519

AGENDAbull Introductionbull Problem Descriptionbull Dynamic Load Balance Algorithm

(DLBA) bull Performance Measurement and

Simulation Models Performance Measurement Simulation Models Simulation Results

bull Conclusion

Introduction

bull The IEEE organization has approved the

80211 standard for Wireless Local Area Networks (WLAN)

bull IEEE 80211 defines two types of wireless networks

IBSS(Independent Basic Service Set)

ESS (Extended Service Set)

IBSS(Independent Basic Service Set)

bull IBSS is also called as ad hoc WLANbull An ad hoc WLAN is limited in its rangebull Within an ad hoc WLAN there is no fixed

wired infrastructure to provide STAs to communicate each other

bull A collection of STAs with wireless network interface may form a network immediately wo the aid of any established infrastructure

CSMACA

bull The fundamental access method of the IEEE 80211 MAC is known as Carrier Sense Multiple Access with Collision Avoidance

bull The CSMACA scheme defines a minimum time gap between two consecutive frames

bull Once a frame has been sent from a station

bull If collision occurs involved stations will select another random amount of time (with a larger backoff window) and wait again

bull They are two ways accessing the stations

1 traditional approachbull 2 load balance approach

Traditional approach

Load balance approach

Problem Descriptionbull Assume that a wireless network consists

of M STAs and N APs bull Each APSTA can access one channel at a

timebull A STA can only select an AP to attach

and each AP is capable of supporting at least M STAs

bull Sx denote a set of STAs which connect to APx and let Rx(y) denote the corresponding RSSI value

ARx = ΣyisinSx Rx(y)SNx where SNx is the number of stations in set Sx

bull Actually a good estimation method should include the quality of transmission which is often measured by the frame error rate (FER)

Dynamic Load Balance Algorithm(DLBA)bull SNx denotes the number of STAs which

connect to APxbull 1048698 Rx(y) denotes the RSSI value between

APx and STAybull 1048698 ARx denotes the average RSSI value in

set Sxbull 1048698 Rmaxdenotes the normalized maximum

RSSI value which can be received and estimated by WLAN adapter

1+(ARxRmax) if Dx(y)gt=0bull p(x)= ⎨ 1-(ARxRmax) if Dx(ylt0 bull The weight of station STAy connects to Apx is

now defined as Wx(y) = Dx(y)timesPx(y) Wx(y) = Dx(y)timesPx(y)bull When a station wants to join a WLAN it

calculates all weights of APs to find the best AP that has the maximum weight

bull Da(y)ltDb(y) station STAy still has a chance to

select APa only when Wa(y)gtWb(y) That is

Da(y)timesPa(y) gt Db(y)timesPb(y) Thus we have Da(y)Db(y)gtPa(y)Pa(y)

Performance Measurement andSimulation Models

Performance Measurementbull Let M and N denote the number of STAs and

the number of APs in WLAN respectively We say that an algorithm is load balancing if all APs have the same number of members ⎣MN⎦ and the average RSSI in WLAN is maximized

Simulation Modelsbull In the simulation two simulation

models are investigated In these two simulation models we compare the degree of load balancing of the proposed DLBA

Conclusion

bull A simple dynamic load balancing algorithm (DLBA) was also proposed to fairly distribute STAs into all APs to derive the maximal total network throughput

bull average RSSI value between AP and STA is very close to that in TA

bull algorithm is very simple and the required calculating time is very small

• Dynamic Load Balance Algorithm (DLBA) for IEEE 80211 Wireless LAN

AGENDAbull Introductionbull Problem Descriptionbull Dynamic Load Balance Algorithm

(DLBA) bull Performance Measurement and

Simulation Models Performance Measurement Simulation Models Simulation Results

bull Conclusion

Introduction

bull The IEEE organization has approved the

80211 standard for Wireless Local Area Networks (WLAN)

bull IEEE 80211 defines two types of wireless networks

IBSS(Independent Basic Service Set)

ESS (Extended Service Set)

IBSS(Independent Basic Service Set)

bull IBSS is also called as ad hoc WLANbull An ad hoc WLAN is limited in its rangebull Within an ad hoc WLAN there is no fixed

wired infrastructure to provide STAs to communicate each other

bull A collection of STAs with wireless network interface may form a network immediately wo the aid of any established infrastructure

CSMACA

bull The fundamental access method of the IEEE 80211 MAC is known as Carrier Sense Multiple Access with Collision Avoidance

bull The CSMACA scheme defines a minimum time gap between two consecutive frames

bull Once a frame has been sent from a station

bull If collision occurs involved stations will select another random amount of time (with a larger backoff window) and wait again

bull They are two ways accessing the stations

1 traditional approachbull 2 load balance approach

Traditional approach

Load balance approach

Problem Descriptionbull Assume that a wireless network consists

of M STAs and N APs bull Each APSTA can access one channel at a

timebull A STA can only select an AP to attach

and each AP is capable of supporting at least M STAs

bull Sx denote a set of STAs which connect to APx and let Rx(y) denote the corresponding RSSI value

ARx = ΣyisinSx Rx(y)SNx where SNx is the number of stations in set Sx

bull Actually a good estimation method should include the quality of transmission which is often measured by the frame error rate (FER)

Dynamic Load Balance Algorithm(DLBA)bull SNx denotes the number of STAs which

connect to APxbull 1048698 Rx(y) denotes the RSSI value between

APx and STAybull 1048698 ARx denotes the average RSSI value in

set Sxbull 1048698 Rmaxdenotes the normalized maximum

RSSI value which can be received and estimated by WLAN adapter

1+(ARxRmax) if Dx(y)gt=0bull p(x)= ⎨ 1-(ARxRmax) if Dx(ylt0 bull The weight of station STAy connects to Apx is

now defined as Wx(y) = Dx(y)timesPx(y) Wx(y) = Dx(y)timesPx(y)bull When a station wants to join a WLAN it

calculates all weights of APs to find the best AP that has the maximum weight

bull Da(y)ltDb(y) station STAy still has a chance to

select APa only when Wa(y)gtWb(y) That is

Da(y)timesPa(y) gt Db(y)timesPb(y) Thus we have Da(y)Db(y)gtPa(y)Pa(y)

Performance Measurement andSimulation Models

Performance Measurementbull Let M and N denote the number of STAs and

the number of APs in WLAN respectively We say that an algorithm is load balancing if all APs have the same number of members ⎣MN⎦ and the average RSSI in WLAN is maximized

Simulation Modelsbull In the simulation two simulation

models are investigated In these two simulation models we compare the degree of load balancing of the proposed DLBA

Conclusion

bull A simple dynamic load balancing algorithm (DLBA) was also proposed to fairly distribute STAs into all APs to derive the maximal total network throughput

bull average RSSI value between AP and STA is very close to that in TA

bull algorithm is very simple and the required calculating time is very small

• Dynamic Load Balance Algorithm (DLBA) for IEEE 80211 Wireless LAN

Introduction

bull The IEEE organization has approved the

80211 standard for Wireless Local Area Networks (WLAN)

bull IEEE 80211 defines two types of wireless networks

IBSS(Independent Basic Service Set)

ESS (Extended Service Set)

IBSS(Independent Basic Service Set)

bull IBSS is also called as ad hoc WLANbull An ad hoc WLAN is limited in its rangebull Within an ad hoc WLAN there is no fixed

wired infrastructure to provide STAs to communicate each other

bull A collection of STAs with wireless network interface may form a network immediately wo the aid of any established infrastructure

CSMACA

bull The fundamental access method of the IEEE 80211 MAC is known as Carrier Sense Multiple Access with Collision Avoidance

bull The CSMACA scheme defines a minimum time gap between two consecutive frames

bull Once a frame has been sent from a station

bull If collision occurs involved stations will select another random amount of time (with a larger backoff window) and wait again

bull They are two ways accessing the stations

1 traditional approachbull 2 load balance approach

Traditional approach

Load balance approach

Problem Descriptionbull Assume that a wireless network consists

of M STAs and N APs bull Each APSTA can access one channel at a

timebull A STA can only select an AP to attach

and each AP is capable of supporting at least M STAs

bull Sx denote a set of STAs which connect to APx and let Rx(y) denote the corresponding RSSI value

ARx = ΣyisinSx Rx(y)SNx where SNx is the number of stations in set Sx

bull Actually a good estimation method should include the quality of transmission which is often measured by the frame error rate (FER)

Dynamic Load Balance Algorithm(DLBA)bull SNx denotes the number of STAs which

connect to APxbull 1048698 Rx(y) denotes the RSSI value between

APx and STAybull 1048698 ARx denotes the average RSSI value in

set Sxbull 1048698 Rmaxdenotes the normalized maximum

RSSI value which can be received and estimated by WLAN adapter

1+(ARxRmax) if Dx(y)gt=0bull p(x)= ⎨ 1-(ARxRmax) if Dx(ylt0 bull The weight of station STAy connects to Apx is

now defined as Wx(y) = Dx(y)timesPx(y) Wx(y) = Dx(y)timesPx(y)bull When a station wants to join a WLAN it

calculates all weights of APs to find the best AP that has the maximum weight

bull Da(y)ltDb(y) station STAy still has a chance to

select APa only when Wa(y)gtWb(y) That is

Da(y)timesPa(y) gt Db(y)timesPb(y) Thus we have Da(y)Db(y)gtPa(y)Pa(y)

Performance Measurement andSimulation Models

Performance Measurementbull Let M and N denote the number of STAs and

the number of APs in WLAN respectively We say that an algorithm is load balancing if all APs have the same number of members ⎣MN⎦ and the average RSSI in WLAN is maximized

Simulation Modelsbull In the simulation two simulation

models are investigated In these two simulation models we compare the degree of load balancing of the proposed DLBA

Conclusion

bull A simple dynamic load balancing algorithm (DLBA) was also proposed to fairly distribute STAs into all APs to derive the maximal total network throughput

bull average RSSI value between AP and STA is very close to that in TA

bull algorithm is very simple and the required calculating time is very small

• Dynamic Load Balance Algorithm (DLBA) for IEEE 80211 Wireless LAN

IBSS(Independent Basic Service Set)

bull IBSS is also called as ad hoc WLANbull An ad hoc WLAN is limited in its rangebull Within an ad hoc WLAN there is no fixed

wired infrastructure to provide STAs to communicate each other

bull A collection of STAs with wireless network interface may form a network immediately wo the aid of any established infrastructure

CSMACA

bull The fundamental access method of the IEEE 80211 MAC is known as Carrier Sense Multiple Access with Collision Avoidance

bull The CSMACA scheme defines a minimum time gap between two consecutive frames

bull Once a frame has been sent from a station

bull If collision occurs involved stations will select another random amount of time (with a larger backoff window) and wait again

bull They are two ways accessing the stations

1 traditional approachbull 2 load balance approach

Traditional approach

Load balance approach

Problem Descriptionbull Assume that a wireless network consists

of M STAs and N APs bull Each APSTA can access one channel at a

timebull A STA can only select an AP to attach

and each AP is capable of supporting at least M STAs

bull Sx denote a set of STAs which connect to APx and let Rx(y) denote the corresponding RSSI value

ARx = ΣyisinSx Rx(y)SNx where SNx is the number of stations in set Sx

bull Actually a good estimation method should include the quality of transmission which is often measured by the frame error rate (FER)

Dynamic Load Balance Algorithm(DLBA)bull SNx denotes the number of STAs which

connect to APxbull 1048698 Rx(y) denotes the RSSI value between

APx and STAybull 1048698 ARx denotes the average RSSI value in

set Sxbull 1048698 Rmaxdenotes the normalized maximum

RSSI value which can be received and estimated by WLAN adapter

1+(ARxRmax) if Dx(y)gt=0bull p(x)= ⎨ 1-(ARxRmax) if Dx(ylt0 bull The weight of station STAy connects to Apx is

now defined as Wx(y) = Dx(y)timesPx(y) Wx(y) = Dx(y)timesPx(y)bull When a station wants to join a WLAN it

calculates all weights of APs to find the best AP that has the maximum weight

bull Da(y)ltDb(y) station STAy still has a chance to

select APa only when Wa(y)gtWb(y) That is

Da(y)timesPa(y) gt Db(y)timesPb(y) Thus we have Da(y)Db(y)gtPa(y)Pa(y)

Performance Measurement andSimulation Models

Performance Measurementbull Let M and N denote the number of STAs and

the number of APs in WLAN respectively We say that an algorithm is load balancing if all APs have the same number of members ⎣MN⎦ and the average RSSI in WLAN is maximized

Simulation Modelsbull In the simulation two simulation

models are investigated In these two simulation models we compare the degree of load balancing of the proposed DLBA

Conclusion

bull A simple dynamic load balancing algorithm (DLBA) was also proposed to fairly distribute STAs into all APs to derive the maximal total network throughput

bull average RSSI value between AP and STA is very close to that in TA

bull algorithm is very simple and the required calculating time is very small

• Dynamic Load Balance Algorithm (DLBA) for IEEE 80211 Wireless LAN

CSMACA

bull The fundamental access method of the IEEE 80211 MAC is known as Carrier Sense Multiple Access with Collision Avoidance

bull The CSMACA scheme defines a minimum time gap between two consecutive frames

bull Once a frame has been sent from a station

bull If collision occurs involved stations will select another random amount of time (with a larger backoff window) and wait again

bull They are two ways accessing the stations

1 traditional approachbull 2 load balance approach

Traditional approach

Load balance approach

Problem Descriptionbull Assume that a wireless network consists

of M STAs and N APs bull Each APSTA can access one channel at a

timebull A STA can only select an AP to attach

and each AP is capable of supporting at least M STAs

bull Sx denote a set of STAs which connect to APx and let Rx(y) denote the corresponding RSSI value

ARx = ΣyisinSx Rx(y)SNx where SNx is the number of stations in set Sx

bull Actually a good estimation method should include the quality of transmission which is often measured by the frame error rate (FER)

Dynamic Load Balance Algorithm(DLBA)bull SNx denotes the number of STAs which

connect to APxbull 1048698 Rx(y) denotes the RSSI value between

APx and STAybull 1048698 ARx denotes the average RSSI value in

set Sxbull 1048698 Rmaxdenotes the normalized maximum

RSSI value which can be received and estimated by WLAN adapter

1+(ARxRmax) if Dx(y)gt=0bull p(x)= ⎨ 1-(ARxRmax) if Dx(ylt0 bull The weight of station STAy connects to Apx is

now defined as Wx(y) = Dx(y)timesPx(y) Wx(y) = Dx(y)timesPx(y)bull When a station wants to join a WLAN it

calculates all weights of APs to find the best AP that has the maximum weight

bull Da(y)ltDb(y) station STAy still has a chance to

select APa only when Wa(y)gtWb(y) That is

Da(y)timesPa(y) gt Db(y)timesPb(y) Thus we have Da(y)Db(y)gtPa(y)Pa(y)

Performance Measurement andSimulation Models

Performance Measurementbull Let M and N denote the number of STAs and

the number of APs in WLAN respectively We say that an algorithm is load balancing if all APs have the same number of members ⎣MN⎦ and the average RSSI in WLAN is maximized

Simulation Modelsbull In the simulation two simulation

models are investigated In these two simulation models we compare the degree of load balancing of the proposed DLBA

Conclusion

bull A simple dynamic load balancing algorithm (DLBA) was also proposed to fairly distribute STAs into all APs to derive the maximal total network throughput

bull average RSSI value between AP and STA is very close to that in TA

bull algorithm is very simple and the required calculating time is very small

• Dynamic Load Balance Algorithm (DLBA) for IEEE 80211 Wireless LAN

bull If collision occurs involved stations will select another random amount of time (with a larger backoff window) and wait again

bull They are two ways accessing the stations

1 traditional approachbull 2 load balance approach

Traditional approach

Load balance approach

Problem Descriptionbull Assume that a wireless network consists

of M STAs and N APs bull Each APSTA can access one channel at a

timebull A STA can only select an AP to attach

and each AP is capable of supporting at least M STAs

bull Sx denote a set of STAs which connect to APx and let Rx(y) denote the corresponding RSSI value

ARx = ΣyisinSx Rx(y)SNx where SNx is the number of stations in set Sx

bull Actually a good estimation method should include the quality of transmission which is often measured by the frame error rate (FER)

Dynamic Load Balance Algorithm(DLBA)bull SNx denotes the number of STAs which

connect to APxbull 1048698 Rx(y) denotes the RSSI value between

APx and STAybull 1048698 ARx denotes the average RSSI value in

set Sxbull 1048698 Rmaxdenotes the normalized maximum

RSSI value which can be received and estimated by WLAN adapter

1+(ARxRmax) if Dx(y)gt=0bull p(x)= ⎨ 1-(ARxRmax) if Dx(ylt0 bull The weight of station STAy connects to Apx is

now defined as Wx(y) = Dx(y)timesPx(y) Wx(y) = Dx(y)timesPx(y)bull When a station wants to join a WLAN it

calculates all weights of APs to find the best AP that has the maximum weight

bull Da(y)ltDb(y) station STAy still has a chance to

select APa only when Wa(y)gtWb(y) That is

Da(y)timesPa(y) gt Db(y)timesPb(y) Thus we have Da(y)Db(y)gtPa(y)Pa(y)

Performance Measurement andSimulation Models

Performance Measurementbull Let M and N denote the number of STAs and

the number of APs in WLAN respectively We say that an algorithm is load balancing if all APs have the same number of members ⎣MN⎦ and the average RSSI in WLAN is maximized

Simulation Modelsbull In the simulation two simulation

models are investigated In these two simulation models we compare the degree of load balancing of the proposed DLBA

Conclusion

bull A simple dynamic load balancing algorithm (DLBA) was also proposed to fairly distribute STAs into all APs to derive the maximal total network throughput

bull average RSSI value between AP and STA is very close to that in TA

bull algorithm is very simple and the required calculating time is very small

• Dynamic Load Balance Algorithm (DLBA) for IEEE 80211 Wireless LAN

Traditional approach

Load balance approach

Problem Descriptionbull Assume that a wireless network consists

of M STAs and N APs bull Each APSTA can access one channel at a

timebull A STA can only select an AP to attach

and each AP is capable of supporting at least M STAs

bull Sx denote a set of STAs which connect to APx and let Rx(y) denote the corresponding RSSI value

ARx = ΣyisinSx Rx(y)SNx where SNx is the number of stations in set Sx

bull Actually a good estimation method should include the quality of transmission which is often measured by the frame error rate (FER)

Dynamic Load Balance Algorithm(DLBA)bull SNx denotes the number of STAs which

connect to APxbull 1048698 Rx(y) denotes the RSSI value between

APx and STAybull 1048698 ARx denotes the average RSSI value in

set Sxbull 1048698 Rmaxdenotes the normalized maximum

RSSI value which can be received and estimated by WLAN adapter

1+(ARxRmax) if Dx(y)gt=0bull p(x)= ⎨ 1-(ARxRmax) if Dx(ylt0 bull The weight of station STAy connects to Apx is

now defined as Wx(y) = Dx(y)timesPx(y) Wx(y) = Dx(y)timesPx(y)bull When a station wants to join a WLAN it

calculates all weights of APs to find the best AP that has the maximum weight

bull Da(y)ltDb(y) station STAy still has a chance to

select APa only when Wa(y)gtWb(y) That is

Da(y)timesPa(y) gt Db(y)timesPb(y) Thus we have Da(y)Db(y)gtPa(y)Pa(y)

Performance Measurement andSimulation Models

Performance Measurementbull Let M and N denote the number of STAs and

the number of APs in WLAN respectively We say that an algorithm is load balancing if all APs have the same number of members ⎣MN⎦ and the average RSSI in WLAN is maximized

Simulation Modelsbull In the simulation two simulation

models are investigated In these two simulation models we compare the degree of load balancing of the proposed DLBA

Conclusion

bull A simple dynamic load balancing algorithm (DLBA) was also proposed to fairly distribute STAs into all APs to derive the maximal total network throughput

bull average RSSI value between AP and STA is very close to that in TA

bull algorithm is very simple and the required calculating time is very small

• Dynamic Load Balance Algorithm (DLBA) for IEEE 80211 Wireless LAN

Load balance approach

Problem Descriptionbull Assume that a wireless network consists

of M STAs and N APs bull Each APSTA can access one channel at a

timebull A STA can only select an AP to attach

and each AP is capable of supporting at least M STAs

bull Sx denote a set of STAs which connect to APx and let Rx(y) denote the corresponding RSSI value

ARx = ΣyisinSx Rx(y)SNx where SNx is the number of stations in set Sx

bull Actually a good estimation method should include the quality of transmission which is often measured by the frame error rate (FER)

Dynamic Load Balance Algorithm(DLBA)bull SNx denotes the number of STAs which

connect to APxbull 1048698 Rx(y) denotes the RSSI value between

APx and STAybull 1048698 ARx denotes the average RSSI value in

set Sxbull 1048698 Rmaxdenotes the normalized maximum

RSSI value which can be received and estimated by WLAN adapter

1+(ARxRmax) if Dx(y)gt=0bull p(x)= ⎨ 1-(ARxRmax) if Dx(ylt0 bull The weight of station STAy connects to Apx is

now defined as Wx(y) = Dx(y)timesPx(y) Wx(y) = Dx(y)timesPx(y)bull When a station wants to join a WLAN it

calculates all weights of APs to find the best AP that has the maximum weight

bull Da(y)ltDb(y) station STAy still has a chance to

select APa only when Wa(y)gtWb(y) That is

Da(y)timesPa(y) gt Db(y)timesPb(y) Thus we have Da(y)Db(y)gtPa(y)Pa(y)

Performance Measurement andSimulation Models

Performance Measurementbull Let M and N denote the number of STAs and

the number of APs in WLAN respectively We say that an algorithm is load balancing if all APs have the same number of members ⎣MN⎦ and the average RSSI in WLAN is maximized

Simulation Modelsbull In the simulation two simulation

models are investigated In these two simulation models we compare the degree of load balancing of the proposed DLBA

Conclusion

bull A simple dynamic load balancing algorithm (DLBA) was also proposed to fairly distribute STAs into all APs to derive the maximal total network throughput

bull average RSSI value between AP and STA is very close to that in TA

bull algorithm is very simple and the required calculating time is very small

• Dynamic Load Balance Algorithm (DLBA) for IEEE 80211 Wireless LAN

Problem Descriptionbull Assume that a wireless network consists

of M STAs and N APs bull Each APSTA can access one channel at a

timebull A STA can only select an AP to attach

and each AP is capable of supporting at least M STAs

bull Sx denote a set of STAs which connect to APx and let Rx(y) denote the corresponding RSSI value

ARx = ΣyisinSx Rx(y)SNx where SNx is the number of stations in set Sx

bull Actually a good estimation method should include the quality of transmission which is often measured by the frame error rate (FER)

Dynamic Load Balance Algorithm(DLBA)bull SNx denotes the number of STAs which

connect to APxbull 1048698 Rx(y) denotes the RSSI value between

APx and STAybull 1048698 ARx denotes the average RSSI value in

set Sxbull 1048698 Rmaxdenotes the normalized maximum

RSSI value which can be received and estimated by WLAN adapter

1+(ARxRmax) if Dx(y)gt=0bull p(x)= ⎨ 1-(ARxRmax) if Dx(ylt0 bull The weight of station STAy connects to Apx is

now defined as Wx(y) = Dx(y)timesPx(y) Wx(y) = Dx(y)timesPx(y)bull When a station wants to join a WLAN it

calculates all weights of APs to find the best AP that has the maximum weight

bull Da(y)ltDb(y) station STAy still has a chance to

select APa only when Wa(y)gtWb(y) That is

Da(y)timesPa(y) gt Db(y)timesPb(y) Thus we have Da(y)Db(y)gtPa(y)Pa(y)

Performance Measurement andSimulation Models

Performance Measurementbull Let M and N denote the number of STAs and

the number of APs in WLAN respectively We say that an algorithm is load balancing if all APs have the same number of members ⎣MN⎦ and the average RSSI in WLAN is maximized

Simulation Modelsbull In the simulation two simulation

models are investigated In these two simulation models we compare the degree of load balancing of the proposed DLBA

Conclusion

bull A simple dynamic load balancing algorithm (DLBA) was also proposed to fairly distribute STAs into all APs to derive the maximal total network throughput

bull average RSSI value between AP and STA is very close to that in TA

bull algorithm is very simple and the required calculating time is very small

• Dynamic Load Balance Algorithm (DLBA) for IEEE 80211 Wireless LAN

ARx = ΣyisinSx Rx(y)SNx where SNx is the number of stations in set Sx

bull Actually a good estimation method should include the quality of transmission which is often measured by the frame error rate (FER)

Dynamic Load Balance Algorithm(DLBA)bull SNx denotes the number of STAs which

connect to APxbull 1048698 Rx(y) denotes the RSSI value between

APx and STAybull 1048698 ARx denotes the average RSSI value in

set Sxbull 1048698 Rmaxdenotes the normalized maximum

RSSI value which can be received and estimated by WLAN adapter

1+(ARxRmax) if Dx(y)gt=0bull p(x)= ⎨ 1-(ARxRmax) if Dx(ylt0 bull The weight of station STAy connects to Apx is

now defined as Wx(y) = Dx(y)timesPx(y) Wx(y) = Dx(y)timesPx(y)bull When a station wants to join a WLAN it

calculates all weights of APs to find the best AP that has the maximum weight

bull Da(y)ltDb(y) station STAy still has a chance to

select APa only when Wa(y)gtWb(y) That is

Da(y)timesPa(y) gt Db(y)timesPb(y) Thus we have Da(y)Db(y)gtPa(y)Pa(y)

Performance Measurement andSimulation Models

Performance Measurementbull Let M and N denote the number of STAs and

the number of APs in WLAN respectively We say that an algorithm is load balancing if all APs have the same number of members ⎣MN⎦ and the average RSSI in WLAN is maximized

Simulation Modelsbull In the simulation two simulation

models are investigated In these two simulation models we compare the degree of load balancing of the proposed DLBA

Conclusion

bull A simple dynamic load balancing algorithm (DLBA) was also proposed to fairly distribute STAs into all APs to derive the maximal total network throughput

bull average RSSI value between AP and STA is very close to that in TA

bull algorithm is very simple and the required calculating time is very small

• Dynamic Load Balance Algorithm (DLBA) for IEEE 80211 Wireless LAN

Dynamic Load Balance Algorithm(DLBA)bull SNx denotes the number of STAs which

connect to APxbull 1048698 Rx(y) denotes the RSSI value between

APx and STAybull 1048698 ARx denotes the average RSSI value in

set Sxbull 1048698 Rmaxdenotes the normalized maximum

RSSI value which can be received and estimated by WLAN adapter

1+(ARxRmax) if Dx(y)gt=0bull p(x)= ⎨ 1-(ARxRmax) if Dx(ylt0 bull The weight of station STAy connects to Apx is

now defined as Wx(y) = Dx(y)timesPx(y) Wx(y) = Dx(y)timesPx(y)bull When a station wants to join a WLAN it

calculates all weights of APs to find the best AP that has the maximum weight

bull Da(y)ltDb(y) station STAy still has a chance to

select APa only when Wa(y)gtWb(y) That is

Da(y)timesPa(y) gt Db(y)timesPb(y) Thus we have Da(y)Db(y)gtPa(y)Pa(y)

Performance Measurement andSimulation Models

Performance Measurementbull Let M and N denote the number of STAs and

the number of APs in WLAN respectively We say that an algorithm is load balancing if all APs have the same number of members ⎣MN⎦ and the average RSSI in WLAN is maximized

Simulation Modelsbull In the simulation two simulation

models are investigated In these two simulation models we compare the degree of load balancing of the proposed DLBA

Conclusion

bull A simple dynamic load balancing algorithm (DLBA) was also proposed to fairly distribute STAs into all APs to derive the maximal total network throughput

bull average RSSI value between AP and STA is very close to that in TA

bull algorithm is very simple and the required calculating time is very small

• Dynamic Load Balance Algorithm (DLBA) for IEEE 80211 Wireless LAN

1+(ARxRmax) if Dx(y)gt=0bull p(x)= ⎨ 1-(ARxRmax) if Dx(ylt0 bull The weight of station STAy connects to Apx is

now defined as Wx(y) = Dx(y)timesPx(y) Wx(y) = Dx(y)timesPx(y)bull When a station wants to join a WLAN it

calculates all weights of APs to find the best AP that has the maximum weight

bull Da(y)ltDb(y) station STAy still has a chance to

select APa only when Wa(y)gtWb(y) That is

Da(y)timesPa(y) gt Db(y)timesPb(y) Thus we have Da(y)Db(y)gtPa(y)Pa(y)

Performance Measurement andSimulation Models

Performance Measurementbull Let M and N denote the number of STAs and

the number of APs in WLAN respectively We say that an algorithm is load balancing if all APs have the same number of members ⎣MN⎦ and the average RSSI in WLAN is maximized

Simulation Modelsbull In the simulation two simulation

models are investigated In these two simulation models we compare the degree of load balancing of the proposed DLBA

Conclusion

bull A simple dynamic load balancing algorithm (DLBA) was also proposed to fairly distribute STAs into all APs to derive the maximal total network throughput

bull average RSSI value between AP and STA is very close to that in TA

bull algorithm is very simple and the required calculating time is very small

• Dynamic Load Balance Algorithm (DLBA) for IEEE 80211 Wireless LAN

bull Da(y)ltDb(y) station STAy still has a chance to

select APa only when Wa(y)gtWb(y) That is

Da(y)timesPa(y) gt Db(y)timesPb(y) Thus we have Da(y)Db(y)gtPa(y)Pa(y)

Performance Measurement andSimulation Models

Performance Measurementbull Let M and N denote the number of STAs and

the number of APs in WLAN respectively We say that an algorithm is load balancing if all APs have the same number of members ⎣MN⎦ and the average RSSI in WLAN is maximized

Simulation Modelsbull In the simulation two simulation

models are investigated In these two simulation models we compare the degree of load balancing of the proposed DLBA

Conclusion

bull A simple dynamic load balancing algorithm (DLBA) was also proposed to fairly distribute STAs into all APs to derive the maximal total network throughput

bull average RSSI value between AP and STA is very close to that in TA

bull algorithm is very simple and the required calculating time is very small

• Dynamic Load Balance Algorithm (DLBA) for IEEE 80211 Wireless LAN

Performance Measurement andSimulation Models

Performance Measurementbull Let M and N denote the number of STAs and

the number of APs in WLAN respectively We say that an algorithm is load balancing if all APs have the same number of members ⎣MN⎦ and the average RSSI in WLAN is maximized

Simulation Modelsbull In the simulation two simulation

models are investigated In these two simulation models we compare the degree of load balancing of the proposed DLBA

Conclusion

bull A simple dynamic load balancing algorithm (DLBA) was also proposed to fairly distribute STAs into all APs to derive the maximal total network throughput

bull average RSSI value between AP and STA is very close to that in TA

bull algorithm is very simple and the required calculating time is very small

• Dynamic Load Balance Algorithm (DLBA) for IEEE 80211 Wireless LAN

Simulation Modelsbull In the simulation two simulation

models are investigated In these two simulation models we compare the degree of load balancing of the proposed DLBA

Conclusion

bull A simple dynamic load balancing algorithm (DLBA) was also proposed to fairly distribute STAs into all APs to derive the maximal total network throughput

bull average RSSI value between AP and STA is very close to that in TA

bull algorithm is very simple and the required calculating time is very small

• Dynamic Load Balance Algorithm (DLBA) for IEEE 80211 Wireless LAN

Conclusion

bull A simple dynamic load balancing algorithm (DLBA) was also proposed to fairly distribute STAs into all APs to derive the maximal total network throughput

bull average RSSI value between AP and STA is very close to that in TA

bull algorithm is very simple and the required calculating time is very small

• Dynamic Load Balance Algorithm (DLBA) for IEEE 80211 Wireless LAN