Living City, A Collaborative Browser-Based Massively Multiplayer Online Game

This work presents the design and implementation of our Browser-based Massively Multiplayer Online Game, Living City, a simulation game fully developed at the University of Messina. Living City is a persistent and real-time digital world, running in the Web browser environment and accessible from users without any client-side installation. Today Massively Multiplayer Online Games attract the attention of Computer Scientists both for their architectural peculiarity and the close interconnection with the social network phenomenon. We will cover these two aspects paying particular attention to some aspects of the project: game balancing (e.g. algorithms behind time and money balancing); business logic (e.g., handling concurrency, cheating avoidance and availability) and, finally, social and psychological aspects involved in the collaboration of players, analyzing their activities and interconnections

A novel scalable hybrid architecture for MMOG

We present a novel MMOG Hybrid P2P architecture and detail its key components, topology and protocols. We highlight the main components which lie at the heart of the proposed solution, and their roles, and describe the methods of tackling the key scenarios which are faced by the architecture during gameplay. For each role, we discuss the interactions that exist between them and describe the protocols that will be used for inter-role communication to perform the atomic actions necessary for maintaining the consistency and responsiveness of an MMOG such as peer addition, peer removal, group transfer, object change persistency and many more. We conclude the chapter with a comparison of the architecture against several existing P2P MMOG frameworks, discussing the differences which exist between them and how the novel Hybrid-P2P architecture we propose aims to address their flaws

Evaluation of Scalability and Communication in MMOGs

Massively Multiplayer Online Games (MMOGs) can involve millions of synchronous players scattered across the world and participating with each other within a single shared game. One of the most significant issues in MMOGs is scalability and it is impact on the responsiveness and the quality of the game. In this paper, we propose a new architecture to increase the scalability without affecting the responsiveness of the game, using a hybrid Peer-to-Peer system. This mechanism consists of central servers to control and manage the game state, as well as super-peer and clone-super-peer to control and manage sub-networks of nodes sharing common regions of the game world. We use the OPNET Modeler to simulate the system and compare the results with client/server system to show the difference in delay and traffic received for various applications such as remote login, database, HTTP, and FTP sessions which are all part of an MMOG system. We use four scenarios for each system to evaluate the scalability of the system with different number of peers (i.e.125, 250, 500, and 1000 peers). The results show that the hybrid P2P system is more scalable for MMOGs when compared with client/server system

Pervasive Games in a Mote-Enabled Virtual World Using Tuple Space Middleware

Pervasive games are a new and exciting field where the user experience benefits from the blending of real and virtual elements. Players are no longer confined to computer screens. Rather, interactions with devices embedded within the real world and physical movements become an integral part of the gaming experience. Several prototypes of pervasive games have been proposed by both industry and academia. However, in such games the issues arising from the integration of players and real world, the management of the context surrounding the players, and the need for communication and distributed coordination are often addressed in an ad-hoc fashion. Therefore, the underlying software fabric is often not reusable, ultimately slowing down the diffusion of pervasive games. In this paper we describe the design and implementation of a pervasive game on top of TinyLIME, a middleware system supporting data sharing among mobile and embedded devices. By illustrating the design of a pervasive game we developed, we argue concretely that the programming abstractions supported by TinyLIME greatly simplify the data and context management characteristics of pervasive games, and provide an effective and reusable building block for their development. TinyLIME was originally designed to support applications where mobile users collect data from sensors scattered in the physical environment. We build upon this capability to put forth a second contribution, namely, the use of wireless sensor devices (or motes) as a computing platform for pervasive games. Besides reporting physical data for the sake of the game, we use motes to store information relevant to the game plot, e.g., virtual objects. Motes are typically very small in size, and therefore can be hidden in the environment, enhancing the sense of immersion in a virtual world. To the best of our knowledge, this original use of wireless sensor devices is novel in the scientific and gaming literature. Furthermore, it is naturally supported by TinyLIME, yielding a unified programming abstraction that spans the heterogeneous gaming platform we propose

Secure referee selection for fair and responsive peer-to-peer gaming

Peer-to-Peer (P2P) architectures for Massively Multiplayer Online Games (MMOG) provide better scalability than Client/Server (C/S); however, they increase the possibility of cheating. Recently proposed P2P protocols use trusted referees that simulate/validate the game to provide security equivalent to C/S. When selecting referees from untrusted peers, selecting non-colluding referees becomes critical. Further, referees should be selected such that the range and length of delays to players is minimised (maximising game fairness and responsiveness). In this paper we formally define the referee selection problem and propose two secure referee selection algorithms, SRS-1 and SRS-2, to solve it. Both algorithms ensure the probability of corrupt referees controlling a zone/region is below a predefined limit, while attempting to maximise responsiveness and fairness. The trade-off between responsiveness and fairness is adjustable for both algorithms. Simulations of three different scenarios show the effectiveness of our algorithms

Applicability of group communication for increased scalability in MMOGs

Massive multiplayer online games (MMOGs) are today the driving factor for the development of distributed interactive applications, and they are increasing in size and complex-ity. Even a small MMOG supports thousands of players, the biggest support hundreds of thousands of concurrent players. Since they are typically built as strict client-server systems, they suffer from the inherent scalability problem of the architecture. Computing power and bandwidth limita-tions close to the server limit the possible number of players. Also, the latency of communication between players through the server will be higher than using direct communication. In the paper, we address these issues and investigate im-provement options. A typical MMOG consists of a virtual world with a con-cept of time and space that is similar to the real world. In it, players are represented by avatars. Only subsets of these avatars interact with each other at any given time. This allows us to divide them into groups, and communication among group members becomes a multi-party communica-tion problem. Thus, to reduce resource consumption, we compare the performance of several algorithms for group communication with the current central server approach. We use overlay multicast as the means of providing group communication, and research algorithms for creating short-est path trees, spanning trees, delay-bounded spanning trees and, more specific, applying Steiner tree heuristics. Our experimental results indicate that different approaches are useful to reduce resource consumption while achieving a good perceived quality under varying conditions, such as frequent changes in group membership and the demand for low latency. 1

Design Issues for Peer-to-Peer Massively Multiplayer Online Games.

Massively Multiplayer Online Games (MMOGs) are increasing in both popularity and scale, and while classical Client/Server (C/S) architectures convey some benefits, they suffer from significant technical and commercial drawbacks. This realisation has sparked intensive research interest in adapting MMOGs to Peer-to-Peer (P2P) architectures. This paper articulates a comprehensive set of six design issues to be addressed by P2P MMOGs, namely Interest Management (IM), game event dissemination, Non-Player Character (NPC) host allocation, game state persistency, cheating mitigation and incentive mechanisms. Design alternatives for each issue are systematically compared, and their interrelationships discussed. We further evaluate how well representative P2P MMOG architectures fulfil the design criteria

Um framework de MMORPG : desenvolvimento orientado pela arquitetura

Monografia (graduação)—Universidade de Brasília, Faculdade UnB Gama, Curso de Engenharia de Software, 2013.Os MMORPGs (Massively Multiplayer Online Role Playing Games) são jogos de computadores que suportam centenas ou milhares de jogadores simultaneamente que controlam um ou mais personagens, interagindo com o ambiente do jogo, completando missões, manipulando objetos do mundo virtual, conversando com outros personagens e combatendo monstros. Este gênero possui a sua jogabilidade como fator crítico para o sucesso, que é significativamente influenciada pela performance dos servidores. Os MMORPGs têm aumentado a sua expressão no mercado de jogos nos últimos anos, entretanto observa-se uma lacuna ferramental que favoreça o reúso no momento da implementação de jogos dessa natureza. Por meio do estudo dos problemas enfrentados no desenvolvimento de novos jogos MMORPGs e do levantamento de requisitos para este tipo de sistema, este trabalho de conclusão de curso apresenta uma proposta de um framework que implementa características essenciais de uma arquitetura de software voltada para MMORPG, com o intuito atenuar essa lacuna. ___________________________________________________________________________ ABSTRACTThe MMORPGs (Massively Multiplayer Online Role Playing Games) are computer games that supports hundreds or thousands of concurrent players con- trolling one or more characters, interacting with the game environment, completing missions, manipulating objects in the virtual world, talking with other players and fighting monsters. This genre has the gameplay as a critical factor for the success, which is significantly influenced by the performance of the servers. MMORPGs have increased its expression in the gaming market in recent years, however, there is a gap tooling that promotes reuse at the time of implementation of such games. Through the study of the problems faced in developing new games of MMORPGs and gathering requirements for this type of system, this work presents a proposal for a framework that implements the essential features of a software architecture oriented to MMORPG in order to mitigate this gap

Disseny i creació d'un videojoc

Català: L’objectiu principal del projecte és el desenvolupament d’un videojoc utilitzant eines que es fan servir habitualment en la indústria dels videojocs, pel desenvolupament de jocs professionals de qualitat. El joc es desenvolupa des del punt de vista d’una petita empresa que comença en el món dels videojocs i que no disposa de grans quantitats de capital per invertir en el projecte. Per tant, s’han tingut en compte especialment aquelles eines que són gratuïtes o amb llicències el menys restrictives possible. Com a objectius específics del joc, volem aconseguir que els personatges controlats per la màquina, tinguin un comportament similar al que podríem esperar d’un jugador humà. Per tant, hauran de ser capaços de navegar per entorns virtuals de forma realista (evitant col·lisions entre altres personatges i obstacles estàtics de la geometria) i hauran de poder compartir informació sobre l’escena i les accions que s’estan duent a terme durant la partida, de manera que els personatges van aprenent i adquirint nou coneixement a mesura que avança la partida, d’una forma similar a la que ho faria un jugador real. A més, volem desenvolupar un mètode automàtic de partició en regions convexes d’un espai virtual, que els personatges utilitzaran per navegar per l’escena evitant els obstacles propis de la geometria, i a més, volem que aquest algorisme serveixi per a qualsevol tipus de geometria

A Distributed Event Delivery Method with Load Balancing for MMORPG

In this paper, we propose a new distributed event delivery method for MMORPG (Massively Multiplayer Online Role Playing Games). In our method, the whole game space is divided into multiple sub spaces with the same size and some player nodes are selected as responsible nodes to deliver game events occurring in their responsible sub spaces. Our method includes (1) a load balancing mechanism which allows each responsible node for the crowded sub space to dynamically construct a tree of multiple nodes and deliver events along the tree to reduce event forwarding overhead per node, (2) a technique to reduce end-to-end event delivery delay by dynamically replacing nodes in the tree, and (3) a technique to efficiently and seamlessly switch sub spaces to be observed while each player’s view moves around in the game space. Through experiments, we show that our method achieves practical performance for MMORPG