elprince_performance evaluation study for hiperlan wlan protocol-final

8/8/2019 Elprince_Performance Evaluation Study for HiperLan WLAN Protocol-FINAL

1/24

Performance Evaluation

Study for HiperLan WLANProtocol

Omar A. ElprinceStudent#220510


2/24

Agenda

Wh at is HIPERLAN?Origin of HIPERLANHIPERLAN MAC

Mec h anismHIPERLAN FamilyFeatures of HiperLAN/2MAC Frame StructureTransport C h annelsTh e C h annel Access Mec h anismSignaling and ControlError ControlSimulation Results


3/24

Wh at is HIPERLAN?

HIPERLAN - HIg h PErformance Radio LANHIPERLAN is a new standard for Radio LANs

developed in Europe by ETSIHIPERLAN is an interoperability standard w h ich specifies a common air interface MAC and PHYlayers in OSI modelHIPERLAN will be a family of standards


4/24

O rigin of HIPERLAN

Early wireless LANs operating in t h e ISM bands(900MHz and 2.45GHz)

Low data rate (~1Mbps) - an indirect result of t h e FCCspread spectrum rules part 15.247.Severe interference environment - from unlike wirelessLANs and ot h er ISM band systems.

Lack of standards - IEEE 802.11 was initiated to satisfyth is need but it was taking time to develop.ETSI set up RES10 group to develop a standard t h atwould be equal in performance to wired LANs suc h asEt h ernet.


5/24


6/24

HIPERLAN MAC

Concept:Fully distributed MAC networks wit h and wit h out infrastructurepermits multi- h op relaying via neig h bors based on LBT (Listenbefore talk)Ch annel Access Mec h anism is based on c h annel sensing and acontention resolution sc h eme calledEY-NPMA - Elimination Yield Non-pre-emptive Priority Multiple

Access using listen-talk contention resolution and using talk-listen Immediate packet acknowledgment.It defines a priority sc h eme and a life time for eac h packet w h ich facilitate t h e control of QoS.

In addition to routing it h andles t h e encryption and power conservation.


7/24

HIPERLAN MAC (Contd)

The Channel Access Mechanism

Th e c h annel access cycle consists of t h ree p h ases: t h eprioritization p h ase, t h e contention p h ase and t h etransmission p h ase.Th e aim of t h e prioritization p h ase is to allow only nodeswith th e h igh est c h annel access priority frame toparticipate in t h e next p h ase.Th e contention p h ase starts immediately after t h e

transmission of th

e prioritization burst, and it furth

er consists of two p h ases: t h e elimination p h ase and t h eyield p h ase.Th e transmission p h ase begins if t h e c h annel is sensedidle during t h e yield listening interval.


8/24

HIPERLAN MAC (Contd)Function:

Station 1

Station 2

Station 3

Station 4

Time

data packet

s tops

stops

stops

pri o ritis a tion conten tion tran smis s ion

Listen

Talk

Listen

Listen

Listen

Talk

Talk

Talk


9/24

PhasesPrioritization Phase

1-5 slots of 168bits (talk)Contentions PhaseElimination - 0-12 slots of 212bits (talk),1 slot of 256bits (listen), prob(talk-listen) = 0.5Yield - 0-9 slots of 168bits (listen), prob(n) = 0.1Tx to Rx turn around time 6 Q s256 contenders, 3.5% collision probabilityTotal of 0-5152bits (0-219 Q s) MAC h eader



10/24

Previous simulations s h ow t h at t h e HIPERLANMAC can simultaneuosly support25 audio links @ 32kbit/s, 10ms delivery25 audio links @ 16kbit/s, 20ms delivery1 video link @ 2Mbit/s, 100ms delivery

Async h file transfer @ 13.4Mbit/s


Performance:


11/24


Operation Parameter SettingParameter ValueCh annel Bit Rate (Mbit/sec) 23.5CAM Priority Levels 5Maximum number of subsequence Eliminationbursts

12

Priority of bursting in an elimination slot

0.5Maximum number of subsequence Yield listening 14Probability of listening in a Yield slot 0.9


12/24

NORMALISE DRESI DU ALLIFETIME

HIGHU SER

D EFINE D

PRIORITY

LOW U SER

D EFINE D

PRIORITYNRL < 10ms 0 110ms < NRL

elprince_performance evaluation study for hiperlan wlan protocol-final

Documents