සංග්‍රාම

Peer-to-Peer Architecture Overview

P2P topologies can be divided into two categories:

• Pure
• Hybrid

A pure P2P network has no central servers, and all clients store a part of the service content and essentially act as both a client and a server. In a hybrid P2P network a central server manages the network, and keeps track of who is part of it and what content each client has stored. Also clients can be classified in a hierarchy. Using pure P2P solution in an MMOG would cause three critical problems:

• The game network could risk getting split up in smaller network, lose parts of the game state or dissolve entirely.
• The clients would have no main point of connection, and hence have no stable way of connecting to the game.
• The game would have no means of a central authority, meaning any client would have potential to cheat.

One research paper propose a Networked Virtual Environments (NVE) P2P system that is optimized for massive fast-paced action games while focusing on scalability and responsiveness of the system. It uses a pure P2P-network with a dynamic connection scheme. Instead of dividing the virtual world into regions of fixed size (matrix solution), each user locally decides to which other users he directly connects. So, it is based on the design of the AOI (Area Of Interest) that is not distance-based (like a circle with a given radius) but based on the number of nearest neighbors (given number of connections). It use this paradim because of human perception to only focus on a limited number of objects at one time. Also by using a publish/subscribe system ( instead of sender-oriented message distribution approach ) for message exchange, an optimal coverage of users’ interests in the NVE and established connections. To ensure global connectivity of the network, a special kind of connections was used which is called "NetConnectors". These NetConnectors prevent a partitioning of the network by connecting every user to another user in at least each of the virtual world’s cardinal directions. It uses a Geocast algorithm allows for sending messages to an arbitrary set of users based on their positions in the NVE. At the end of the paper, it provided statistics of simulated game by using these techniques.

References

• Hybrid Peer-to-Peer Solution for MMORPGs

  a thesis by Frode Voll Aasen & Tom-Christian Bjørlo Johannessen

• A scalable Peer-to-Peer-overlay for real-time massively multiplayer online games

  by Philip Mildner, Tonio Triebel, Stephan Kopf, Wolfgang Effelsberg

Decentralized Client/Server Architecture Overview

Decentralized client-server architecture is the most popular architectures used in MMOGs.Clients connect to servers,and servers connect to each other. The inter serve communication is like a peer to peer network. This approach helps to have a good transparency as a distributed system. If one server fails, the clients will not know about it, as there are many servers which will take care of the fault tolerance of the system. So, the developers have to come up with efficient architectures and algorithms to handle server to server communication. Since it is not centralized, the risk of single point of failure is non-existing. Colyseus , a distributed architecture for online multi player games is an example of such a decentralized client-server architecture. Developers can use zoning, instancing and replication techniques to enhance the efficiency of this kind of systems.

Project Documentation

As the project progress, we will create documentation on academic papers and presentation slides related to our project. All the documentations will be in PDF format.

Introductory slides