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IVR Presentation. Topic :A peer-to-peer message exchange scheme for large scale networked virtual environment. (N19) Presented by Feng SHEN, u3390679. Content table. Some keywords Background of this paper Peer-to-peer message exchange scheme Simulation Questions. Keyworkds. - PowerPoint PPT Presentation
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IVR PresentationIVR Presentation
Topic:A peer-to-peer message exchange scheme for large scale networked virtual environment. (N19)
Presented by Feng SHEN, u3390679
Content tableContent table
Some keywordsBackground of this paperPeer-to-peer message exchange schemeSimulationQuestions
KeyworkdsKeyworkds
Net-VE: Networked Virtual EnvironmentP2P: Peer-to-peerS/C: Server/Client architectureAOIM: Area of Interest Management
BackgroundBackground
2002, multi-user based game & application become a big business
Increase of user numberRequire high performance hardware &
complex software systems
MMORPG in 2002MMORPG in 2002
EverQuest holds 400,000 registered usersInteract in one consistent VE in real-timeBig challenge for system scalabilityDominant factor affects scalability
-- the way to exchange updated message
Solution in 2002Solution in 2002
To solve the problem, many communication architectures are proposed
Peer-to-peerServer/client architecture
P2P architectureP2P architecture
Unicast– O(N2) for N entities– bad performance for large N
Multicast combined with area partioning scheme– works well, but multicast not widely
avaliable on the Internet
Server/ClientServer/Client
Entity Server entitiesServer – bottleneckFailure of server = failure of whole systemMulti-server/client
* Over-provision
* Estimate no of entities
* Too costly for large-scale applications
Proposal of this paperProposal of this paper
Scalable p2p message exchange schemePeer-to-peer architecture No multicast infastructureNo centralized mechanism
Details of schemeDetails of scheme
A. Bootstrap methodB. Creating overlay network
– Each entity connects neighbouring entities– Scheme keeps latency smaller than S/C
architecture– Network deployed without multicast
infastructure
AA. Bootstrap method. Bootstrap method
Procedure for an entity enters VE for the first time
This entity acquire information of other entities already in VE
BB. Creating overlay network. Creating overlay network
Entity acquire surrounding entities Classify into two groups AE & LE
– AE: Active entities, direct interacation, detail information
– LE: Latent entities, potiential interaction, rough information
Take the nearest N entities as AE Unicast connects AE
Exchange messageExchange message
Information of AE exchanged through unicast connection
Information of LE– Each entity compress its AEs’ rough information into
list– Exchange this list with its AEs’ lists– Knows LE’s location
They should recognize each other, establish direct connection, set AE
SimmulationSimmulation
Key issue of creating Neted VE – to keep optimal adjacency relationship of
entities in VE
Compare result with that from S/C schemeShow scalability & performance
S/C entity processorS/C entity processor
1. Calculates the entities location at time T2. Calculates the distance among all the
entities to generate a distance table3. According to the table, inform the nearest
N entities of each entity as Active Entity
P2P entity processorP2P entity processor 1.Updates the location of entity “I” (Entity(I)) at time T 2.Inquire its neighboring entities (Entity(I).AE(J))
about their current locations 3.Then inquire the neighboring entities about the
information of their neighboring entities (Entity(Entity(I).AE(J).ID).AE(K)))
4.Calculates the distance among the entities based on the information acquired in the previous step and sort them in order of the distance
5.Set the nearest N enteritis as new Active Entities
Qualitative analysisQualitative analysis
Two models resemble each other To evaluate quantitatively, define
N: the no of entities in VEP(I): the no of AEs for entity I in P2P modeQ(I): the no of AEs for entity I in S/C mode
ConsistencyConsistency
The P2P based message exchange scheme makes it possible for entities to establish almost consistent relationship (>0.9) compared to S/C scheme, independently of the number of the participants in the virtual environment.
This scheme scales well.
ConclusionConclusion
The proposed P2P message exchange scheme can build consistent virtual environment in a scalable manner.
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