Cơ bản về Cloud gaming

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Cơ bản về Cloud gaming

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Tài liệu hữu ích cho những người mới tìm hiểu về Cloud gaming, bao gồm: sơ đồ hệ thống, ưu điểm, nhược điểm, những khó khăn đang gặp phải của lĩnh vực này và case study. Bên cạnh đó giới thiệu một số thành tựu đạt được hiện tại và định hướng trong tương lai về cloud gaming.

Distributed System Report CLOUD GAMING Distributed System Report Table of Contents CLOUD GAMING I INTRODUCTION II OVERVIEW .4 III ISSUES AND CHALLENGES A Interaction Delay Tolerance .6 B Video Streaming and Encoding C Security .8 IV CLOUD GAMING FRAMEWORK V CLOUD GAMING PLATFORMS A System Integration B Quality of Service Evaluations 11 C Quality of Experience Evaluations 14 VI OPTIMIZING CLOUD GAMING PLATFORMS 15 A Cloud Server Infrastructure 15 B Communications .18 VII REAL WORLD PERFORMANCE: ONLIVE .22 A Measuring Interaction Delay 23 B Measuring Image Quality 24 VIII IX COMMERCIAL CLOUD GAMING SERVICES 27 A CASE STUDY ON CLOUD GAMING .29 A System Architecture 29 B The 2005 Software and Business Model 30 C Changes in the Software and Business Model 31 D Lessons Learned .32 X SOME POPULAR CLOUD GAMING SERVICES IN 2019 34 A Free Cloud Gaming 34 B of the Best Cloud Gaming Services [106] .35 XI CONCLUSION AND FURTHER DISCUSSION 38 REFERENCES 39 Page Distributed System Report CLOUD GAMING I INTRODUCTION The wide-used of the cloud computing has led the gaming industry to a revolution that changes the way human play games This up-and-coming technology called cloud gaming, also known as gaming on demand, is a concept that involves many of distributed computers connected through a synchronous communication network The service of documents and file sharing has been altered in gaming industry to adjust the development of cloud gaming Cloud gaming is an innovative application that offers new opportunities for both upcoming and existing games based on cloud computing Under the running mode of cloud gaming, all the games are stored in the operators’ or game company’s server so that direct streaming of video sequence onto electric devices such as computers and consoles over internet are allowed The thin client in low-end only gives requests to high-end server which deals with these requests and streams game experience back as a response Games are held and run in remote servers so that no downloading is needed for client side and all updates are completed within these servers Figure below shows the basic idea of cloud gaming Page Distributed System Report Figure Basic idea for cloud gaming As a result, cloud gaming liberates users from the need to necessarily update their devices and handles compatibility issues while accessing games from servers Users not need to master the functionalities and operation of infrastructure in a cloud or relevant professional knowledge As an advantage, less powerful computation is required to run a high-quality game and offer great performance One of other advances is the cost of purchasing a gaming console or a high configuration computer to support a greater computational performance can be reduced Furthermore, time is saved due to downloading, installing and updating are no more exist onto local host Over recent years, events surrounding this emerging technology have been successive occurred all over world; moreover, researches and exploitations are conducting and improving to expand advances in cloud technology to allow processing both traditional and complicated computation in an efficient way Onlive and Gaikai are two industrial pioneers of cloud gaming, both having seen great success with multimillion user bases The recent 380 millions dollar purchase of Gaikai by Sony, an industrial giant in digital entertainment and consumer electronics, shows that cloud gaming is beginning to move into the mainstream From the perspective of industry, cloud gaming can bring immense benefits by expanding the user base to the vast number of less-powerful devices that support thin clients only, particularly smartphones and tablets As an example, the recommended system configuration or Battlefield 3, a highly popular first-person shooter game, is a quad-core CPU, GB RAM, 20 GB storage space, and a graphics card with at least 1GB RAM (e.g., NVIDIA GEFORCE GTX 560 or ATI RADEON 6950), which alone costs more than $500 The newest tablets (e.g., Apple’s iPad with Retina display and Google’s Nexus 10) cannot even meet the minimum system requirements that need a dual-core CPU over 2.4 GHz, GB RAM, and a graphics card with 512 MB RAM, not to mention smartphones of which the hardware is limited by their smaller size and thermal control Furthermore, mobile terminals have different hardware/software architecture from PCs, e.g., ARM rather than x86 for CPU, lower memory frequency and bandwidth, power limitations, and distinct operating systems As such, the traditional console game model is not feasible for such devices, which in turn become targets for Gaikai and Onlive Cloud gaming also reduces customer support costs since the computational hardware is now under the cloud gaming provider’s full control, and offers better Digital Rights Management (DRM) since the codes are not directly executed on a customer’s local device However, cloud gaming remains in its early stage and there remain significant theoretical and practical challenges towards its widespread deployment In this article, we conduct a systematic analysis of state-of-the-art cloud gaming platforms, both in terms of their design and their performance We first offer an intuitive description of the unique design considerations and challenges addressed by existing platforms We highlight their framework design Using Onlive as a representative, we then measure its real world performance with different types of games, for both interaction latency and streaming quality Page Distributed System Report Many cloud-based gaming companies such as OnLive and Gaikai recently has started offering services and platforms to allow users to play high-definition video games rendered on remote cloud servers At the Game Developers Conference in 2009, OnLive and Gaikai announced to release its services in the winter of 2009 and even earlier, few years before that conference, G-cluster has launched the first deployment of cloud gaming in Japan in 2004 just after Phantom Entertainment presented cloud gaming console in 2002 All these events have turned cloud gaming into reality Finally, we discuss the future of cloud gaming as well as issues yet to be addressed II OVERVIEW Basically, cloud gaming are implemented using client-server structure where server side is a group of many connected computers Client side is a thin client acting as an interface that collects commands and requests from gamers and it can be a gaming console, a personal computer or a mobile device All the data is gathered and transferred to cloud A TCP is first established to create a UDP link so that cloud responses client side with a UDP communication port number to set up a connection between two sides In detail, UDP link delivers the client input and commands to cloud while TCP receives response which can either be a video stream or a file stream from servers Figure Overview of a cloud gaming platform After cloud gaming platform gains the user inputs, as shown in Figure above, servers start analyzing incoming data to produce game actions depending on game logics Similarly to live media streaming, cloud gaming quickly encodes/compresses videos rendered from GPU and Page Distributed System Report allocates them to client sides However, compared to live media streaming, a command issued by a gamer is transferred to cloud through Internet without capacity to buffer video frames on local host Finally, once complete frames have been decoded from video stream from TCP connection, a specific server in the cloud then captures and encodes these frames and sends to front end where displays them to players III ISSUES AND CHALLENGES Despite the great opportunities of cloud gaming, several crucial challenges must be addressed by the research community before it reaches its full potentials to attract more gamers, game developers, and service providers We summarize the most important aspect as follows First, cloud gaming platforms and test beds must be built up for comprehensive performance evaluations The evaluations include measurements on Quality of Service (QoS) metrics, such as energy consumption and network metrics, and Quality of Experience (QoE) metrics, such as gamer perceived experience Building platforms and test beds, designing the test scenarios, and carrying out the evaluations, require significant efforts, while analyzing the complex interplay between QoS and QoE metrics is even more difficult Second, the resulting platforms and evaluation procedures allow the research community to optimize various components, such as cloud servers and communication channels More specifically, optimization techniques for: (i) better resource allocation and distributed architecture are possible at cloud servers, and (ii) optimal content coding and adaptive transmissions are possible in communication channels Third, computer games are of various game genres These genres can be categorized on the basis of two elements: viewpoint and theme Viewpoint is how a gamer observes the game scene It determines the variability of rendered video on the screen Most commonly seen viewpoints include first-person, second-person, third-person, and omnipresent First-person games adopt graphical perspectives rendered from the viewpoint of the in-game characters, such as in Counter-Strike Second-person games are rendered from the back of the in-game characters, so that gamers can see the characters on the screen, like in Grand Theft Auto Third-person games fix the gamers’ views on 3D scenes, projected onto 2D spaces Modern third-person games usually adopts the sky view, also known as God view Classic third-person games include Diablo, Command & Conquer, FreeStyle, and etc Last, omnipresent enables gamers to fully control views on the region of interest (RoI) from different angels and distances Many recent war games, e.g., Age of Empires 3, Stronghold 2, and Warcraft III, fall into this category Game theme determines how gamers interact with game content Common themes include shooting, fighting, sports, turn-based role-playing (RPG), action role-playing (ARPG), turn-based strategy, real-time strategy (RTS), and management simulation Although the viewpoint may be restricted by game theme, but generally a game genre can be describe by a pair of viewpoint and theme, such as first-person shooting, third-person ARPG, Page Distributed System Report omnipresent RTS, and etc Among them, fast paced first-person shooting games impose the highest scene complexity, which are the most challenging games for cloud gaming service providers In contrast, third-person turn-based RPG games are least sensitive to delays and thus more suitable for cloud gaming From low latency live video streaming to high performance 3D rendering, cloud gaming must bring together a plethora of bleeding edge technologies to function We begin our analysis with the important design considerations, which are currently being addressed by cloud gaming providers A cloud gaming system must collect a player’s actions, transmit them to the cloud server, process the action, render the results, encode/compress the resulting changes to the gameworld, and stream the video (game scenes) back to the player To ensure interactivity, all of these serial operations must happen in the order of milliseconds Intuitively, this amount of time, which is defined as interaction delay, must be kept as short as possible in order to provide a rich experience to the cloud game players However, there are tradeoffs: the shorter the player’s tolerance for interaction delay, the less time the system has to perform such critical operations as scene rendering and video compression Also, the lower this time threshold is, the more likely a higher network latency can negatively affect a player’s experience of interaction With this is mind, we start our design discussion with delay tolerance A Interaction Delay Tolerance Table I Delay Tolerance In Traditional Gaming Example Game Type Perspective Delay Threshold First Person Shooter (FPS) First Person 100 ms Role Playing Game (RPG) Third Person 500 ms Real Time Strategy (RTS) Omnipresent 1000 ms Studies on traditional gaming systems have found that different styles of games have different thresholds for maximum tolerable delay Table I summarizes the maximum delay that an average player can tolerate before the Quality of Experience (QoE) begins to degrade As a general rule, games that are played in the first person perspective, such as the shooter game Counter Strike, become noticeably less playable when actions are delayed by as little as 100 ms This low delay tolerance is because such first person games tend to be action-based, and players with a higher delay tend to have a disadvantage In particular, the outcome of definitive game changing actions such as who “pulled the trigger” first can be extremely sensitive to the delay in an action-based First Person Shooter (FPS) game Third person games, such as Role Playing Games (RPG), and many massively multiplayer games, such as World of Warcraft, can often have a higher delay tolerance of up to 500 ms This is because a player’s commands in such games, e.g., use item, cast spell, or heal character, are generally executed by the player’s avatar; there is often an invocation phase, such as chanting magic words before a spell is cast, and hence the player does not expect the action to be instantaneous The actions must still be registered in a Page Distributed System Report timely manner, since the player can become frustrated if the interaction delay causes them a negative outcome, e.g., they healed before an enemy attack but still died because their commands were not registered by the game in time The last category of games are those played in an “omnipresent” view, i.e., a top down view looking at many controllable entities Examples are Real Time Strategy (RTS) games like Star Craft and simulation games such as The Sims Delays of up to 1000 ms can be acceptable to these styles of games since the player often controls many entities and issues many individual commands, which often take seconds or even minutes to complete In a typical RTS game, a delay of up to 1000 ms for a build unit action that takes over a minute will hardly be noticed by the player Although there is much similarity between interaction delay tolerance for traditional gaming and cloud gaming, we must stress the following critical distinctions First, traditionally, the interaction delay was only an issue for multi-player online gaming systems, and was generally not considered for single player games Cloud gaming drastically changes this; now all games are being rendered remotely and streamed back to the player’s thin client As such, we must be concerned with interaction delay even for a single player game Also, traditional online gaming systems often hide the effects of interaction delay by rendering the action on a player’s local system before it ever reaches the gaming server For example, a player may instruct the avatar to move and it immediately begins the movement locally; however the gaming server may not receive the update on the position for several milliseconds Since cloud gaming offloads its rendering to the cloud, the thin client no longer has the ability to hide the interaction delay from the player Visual cues such as mouse cursor movement can be delayed by up to 1000 ms, making it impractical to expect the player will be able to tolerate the same interaction delays in cloud gaming as they in traditional gaming systems We conjecture that the maximum interaction delay for all games hosted in a cloud gaming context should be at most 200 ms Other games, specifically such action-based games as first person shooters likely require less than 100 ms interaction delay in order not to affect the players QoE Recent research using subjective tests have indicated the that this is indeed the case B Video Streaming and Encoding We next examine the video streaming and encoding needs of a cloud gaming system Cloud gaming’s video streaming requirements are quite similar to another classical application, namely, live media streaming Both cloud gaming and live media streaming must quickly encode/compress incoming video and distribute it to end users In both, we are only concerned with a small set of the most recent video frames and not have access to future frames before they are produced, implying encoding must be done with respect to very few frames However, live video streaming and cloud gaming also have important differences First, compared to live media streaming, cloud gaming has virtually no capacity to buffer video frames on the client side This is because, when a player issues a command to the local thin client, the Page Distributed System Report command must traverse the Internet to the cloud, be processed by the game logic, rendered by the processing unit, compressed by the video encoder and streamed back to the player Given that this must all be done in under 100 - 200 ms, it is apparent that there is not much margin for a buffer Live media streaming on the other hand can afford a buffer of hundreds of milliseconds or even a few seconds with very little loss to the QoE of the end user The sensitive real time encoding needs of cloud gaming make the choice of video encoder of paramount importance for any cloud gaming provider Currently, the major cloud gaming providers Gaikai and Onlive both use versions of the H.264/MPEG-4 AVC encoder Gaikai uses a software based approach for encoding where as Onlive is using specialized hardware to compress its cloud gaming video streams In either case the choice of the H.264 encoder is motivated by the fact that the encoder not only has a very high compression ratio but also that it can be configured to work well with stringent real time demands C Security Security is a potential challenge in cloud gaming especially data protection and location In-house gaming allows players to establish a personal computing environment and to locate the data storage in detail as well as well handling while gaming in cloud hardly supports finding specific information as all data is stored redundantly in several physical locations without producing detailed location information [1] Due to the difficulty of capturing data efficiently, sufficient safeguards are troublesome to be ensured whether they are in place and if legal provisions are met Data protection and privacy are often indicated as primary risks in cloud in where personal information is stored and located [2] There are many location based services exist that use the location of the user to services Although these services offer convenient to communities, user information disclosure may result in the loss of user benefits In some cases, personal data can be embezzled and shifted to commit a crime such as filching virtual currency and defrauding other players In addition, security management is made to analyse and control the risks raised by virtualisation in order to mitigate the risks appropriately Table II gives a table containing critical risk areas in virtualisation and cloud computing [3] Risk area Information security Operations management Change management Disaster recovery/ Business continuity planning Third-party/ service level management Interface management Regulations and legislation Table II Critical risk area [3] Critical Some-what important 91.7% 8.3% 41.7% 58.3% 41.7% 50.0% Not so important 0.0% 0.0% 8.3% 66.7% 33.3% 0.0% 41.7% 41.7% 16.6% 8.3% 33.3% 50.0% 41.7% 41.7% 25.0% Page Distributed System Report IV CLOUD GAMING FRAMEWORK Based on the design considerations we have been discussing, we now outline a generic framework for a cloud gaming system As can be observed, a player’s commands must be sent over the Internet from its thin client to the cloud gaming platform Once the commands reach the cloud gaming platform they are converted into appropriate in-game actions, which are interpreted by the game logic into changes in the game world The game world changes are then processed by the cloud system’s graphical processing unit (GPU) into a rendered scene The rendered scene must be compressed by the video encoder, and then sent to a video streaming module, which delivers the video stream back to the thin client Finally, the thin client decodes the video and displays the video frames to the player To confirm the representability of this generic framework, we have conducted a traffic measurement and analysis from the edge of four networks which are located in the United States, Canada, China and Japan We recorded the packet flow of both Gaikai and Onlive After that, we used Wireshark to extract packet-level details, which reveal the existence of thin clients and their interactions with remote cloud servers We also discover that Gaikai is implemented using two public clouds, namely Amazon EC2 and Limelight When a player selects a game on Gaikai, an EC2 virtual machine will first deliver the Gaikai game client to the player After that, it forwards the IP addresses of game proxies that are ready to run the selected games to the players The player will then select one game proxy to run the game For multiplayer online games, these game proxies will also forward the players’ operations to game servers and send the related information/reactions back to the players Onlive’s workflow is quite similar, but is implemented with a private cloud environment Using public clouds enables lower implementation costs and higher scalability; yet a private cloud may offer better performance and customization that fully unleash the potentials of cloud for gaming Hence, we use Onlive in the following measurement and analysis V CLOUD GAMING PLATFORMS This section presents the work related to cloud gaming platforms in three steps: (i) integrated cloud gaming platforms for complete prototype systems, (ii) measurement studies on QoS metrics, and (iii) measurement studies on QoE metrics A System Integration Providing an easy-to-use platform for (cloud) game developers is very challenging This is because of the complex, distributed, and heterogeneous nature of the cloud gaming platforms In fact, there is a clear tradeoff between development complexity and optimization room Platforms opt for very low (or even no) additional development complexity may suffer from limited room for optimization, which are referred to as transparent platforms that run unmodified games In contrast, other platforms opt for more optimized performance at the expense of requiring additional development complexity, such as code augmentation and recompilation, which are Page Distributed System Report Figure The 2010 business model G-cluster removed unnecessary third parties from the business model because of changes to the entire product and changes in the target market C Changes in the Software and Business Model Figure represents G-cluster’s 2010 business model, which is simpler and has fewer actors It no longer includes video-on-demand service providers, set-top box manufacturers, middleware providers, or portals This difference has two main causes: a change in the target market and a change in the software provided In 2010, the target customers were IPTV users The PC gaming market had become extremely competitive, and finding a segment on which to focus was hard For PC players, games have increasingly become free In addition, well-known games are extremely expensive to license for games-ondemand services All this meant that the PC market became too difficult to penetrate and develop into a successful business So, G-cluster focused back on the IPTV market Nevertheless, operating in the PC market had let the firm test the product, obtain feedback, and gain experience These opportunities enabled G-cluster to develop the product further for the IPTV market The target group for G-cluster’s games-on-demand service also crystallized In practice, the service seems best suited to “mid-class” users Occasional users are unwilling to pay for the service because free games are available (although they’re much simpler than G-cluster’s games) Heavy users tend to buy games in stores and play very complex games They are also willing to invest in consoles and other equipment G-cluster’s service thus appeals to the middle category of users that favors “easy to use” games, such as Nintendo Wii games This middle category forms a very large group, as the success of Nintendo’s Wii has shown Page 31 Distributed System Report Regarding the software, G-cluster now offers a “whole product” for network operators.12 In 2005, G-cluster provided only the server platform and gaming content In 2010, it offered a ready-made product portfolio including components previously provided by value-adding mediators or network portals The firm now includes an invoicing system and a user interface (menu) that lets users select the games from its virtual games store The comprehensiveness of its offerings has enabled better access to network operators with no need for software components from a large number of intermediaries In addition, G-cluster got to know the operators better between 2005 and 2010 and can more readily make direct contact with them The change in target customers to IPTV users and the individualized menu have let it remove portals from the value chain Altogether, these changes have made G-cluster less dependent on third parties The only third party between Gcluster and the network operators is a large, well-known server manufacturer G-cluster is still relatively small; thus, cooperation with the large firm helps it negotiate with new network operators However, G-cluster conducts no actual business with the server manufacturer; instead, the cooperation benefits both firms G-cluster gets marketing and sale resources from the firm, which already knows the network operators and conducts business with them By including G-cluster’s technology on its servers, the manufacturer gets added value, which it can advertise when selling servers to network operators In the current business model, G-cluster also offers a software development kit (SDK) for game licensors By using the SDK, licensors can modify and integrate a game directly for Gcluster’s gaming platform and send it to network operators Nevertheless, G-cluster undertakes quality assurance for all games before network operators can offer them to customers The longterm plan is to outsource all the integration work to game developers In this way, developers can take the requirements of G-cluster’s gaming platform into consideration right from the start The SDK decreases integration costs and lets G-cluster launch new, more expensive games As Figure shows, the revenue is now divided among three actors instead of four This, together with other business model changes, has doubled the average revenue per user In addition, G-cluster’s service is now accessible to 3,000,000 households D Lessons Learned A business model must provide value to the actors in the supply chain G-cluster’s business model has provided added value to actors in the game services supply chain and to customers Over five years, both internal changes (product development) and external changes (competition in the PC games market) have impacted G-cluster’s business model The lessons learned from the G-cluster experience are applicable to a broader population—that is, software firms whose business model includes providing cloud services through the Internet Page 32 Distributed System Report 1) Aim at a Whole Product By adding the invoicing and user interface software, G-cluster created a product that contains all the modules needed and satisfies the operators’ needs With this business model, Gcluster has become less dependent on third parties and has improved profitability by reducing the number of the partners who share end-user revenue This implies that firms should simplify the value chain as soon as possible Certain third parties were important in G-cluster’s start-up phase because they provided knowledge and software modules that the firm didn’t have These parties also acted as marketing channels at a time when G-cluster lacked legitimacy in the market However, when the firm achieved an entire product and a feasible market position, costly partners became unnecessary 2) Shift to a Platform Layer G-cluster’s development of the SDK made it more profitable to include new games for its service The new business model decreased G-cluster’s modification of games and increased the range of available games Although this decreased the income per game, it boosted the total volume So, a shift in emphasis in the architectural layers, from the games layer to the platform layer, let G-cluster focus on developing the core product Generally, firms must develop alternative business models to keep their products competitive for customers and maintain profitability for revenue-sharing partners 3) Balance the Platform Strategy and Operators’ Roles Network operators can guarantee the quality of gaming-as-a-service They also possess the customer contacts and have the infrastructure for operating cloud services A small firm such as G-cluster couldn’t achieve the market volume that would let it operate the platform and games on its own, bypassing the operators So, providing full PaaS software for network operators and associated tools for game licensors has let G-cluster establish a feasible platform strategy in its business model Use Indirect Network Effects The server manufacturer acted as an important new third party in the business model, even though there were no major business transactions or contracts between it and G-cluster The partner now acts as a reliable marketing channel, increasing G-cluster’s market credibility and helping to find good contacts on the customer side, which will prove useful when G-cluster negotiates with large network operators This indicates that small software firms should exploit the positive indirect network effects of its partners 4) Exploit SaaS Advantages Game licensors appreciate the SaaS model for various reasons Executing the games on a cloud server makes illegal copying practically impossible It’s also easy to benefit from the long Page 33 Distributed System Report tail when offering SaaS In a virtual store, shelf space costs nothing, and the licensor can offer a large number of games for longer than traditional games offered in stores—given that a game’s life cycle is relatively short and shelf space is costly 5) Adapt to Infrastructure Technology Changes The IP protocol has been seen as a unifying platform for future applications However, a plethora of network variants, infrastructure components, interfaces, and standards wars are still impacting the market reach of any software-based system As we described, G-cluster changed its business model from IPTV users to PC users—and then back to IPTV users These changes were based on technical developments and competition in the market However, these business model changes haven’t impacted G-cluster’s product strategy because the same gaming platform can deliver games for PC and IPTV The only technical change was coding the command buttons of the PC games for IPTV users X SOME POPULAR CLOUD GAMING SERVICES IN 2019 A Free Cloud Gaming As you can imagine, the tech that goes into cloud gaming is expensive, not only to purchase, but also to maintain Despite that, there’s a high demand for free cloud gaming The term “free cloud gaming” is searched globally about 6,500 times per month on Google, even though there aren’t many free cloud gaming services out there [105] Page 34 Distributed System Report In fact, we couldn’t find any during our research, but given the volume, it wouldn’t be surprising to see some pop up in the future Let this serve as a PSA, if nothing else If you find a cloud gaming service that claims to be free, it’s best to stay away B of the Best Cloud Gaming Services [106] 1) PlayStation Now [107] The biggest losers in the console war between Sony and Microsoft are the gamers who can’t play games which are exclusive to the other platform With a PlayStation Now streaming subscription, you can solve the problem All you need is a PC and a suitable controller (or a PS4, if you just want to play old-school games) It has “over 250” PS4 games ready to roll, with new games being added every month Sony uses its extensive back catalog to fill up the rest, with hundreds of additional PS2 and PS3 games to play for the nostalgia factor It’s available for streaming in 12 countries currently, with further expansion planned A one-month subscription should set you back $19.99/month, but Sony does offer a seven-day trial period to let you see if the service is for you Page 35 Distributed System Report 2) GeForce Now [108] Nvidia GeForce Now originally launched as a remote streaming service with subscribers streaming any number of offered games to a PC or an Nvidia gaming device The newer service, available for Windows and macOS users, does away with the games while keeping the backbone – it’s a remote gaming PC for hire Using a service like Steam or Epic, you can download and install the games remotely and play them on a PC, Mac or Nvidia device The service is currently free for users during beta testing, but you can apply to join the waiting list If you have a Shield TV device, you should be able to sign up straight away 3) Vortex [109] Page 36 Distributed System Report If you don’t want the hassle of installing games, Vortex would be a good alternative It lets you stream a selection of PC games to a Mac or to a lesser-powered PC or laptop Its killer feature is mobile streaming, however, as it lets you stream PC games to Android and iOS devices using the Vortex app Vortex offers around 100 existing games, with some big names like Fornite and GTA included New games are added regularly, too Some are ready to play, while others might require you to prove ownership using your Steam account login A subscription will set you back $9.99/month 4) Shadow [110] The Shadow cloud gaming service is more like GeForce Now than Vortex Rather than providing you with limited game streaming, you can hire your own remote, high-powered gaming PC This will let you stream almost any game or program you like on their platform That includes streaming to a low-powered PC, a Mac, mobile devices or TV The downside is ultimately the cost, with a one-month package costing $34.95/month, or an equivalent of $24.95/month if you pay for it in full upfront There’s no trial, but you can try the service out for $9.95 for 10 days 5) Parsec [111] Parsec offers a DIY approach for gamers who want to build their own streaming service for games It’s free to download and use, but you supply the gaming hardware yourself, which you can then stream remotely Page 37 Distributed System Report It supports multi-play, so you can share one game with multiple players, even if the game doesn’t support online play itself You can also turn it into a fully cloud-based solution using an Amazon GPU-powered virtual machine (although this will cost you) XI CONCLUSION AND FURTHER DISCUSSION This article has closely examined the framework design of state-of-the-art cloud gaming platforms We have also measured the performance of Onlive, one of the most representative and successful cloud gaming platforms to date The results, particularly on interaction latency and streaming quality under diverse game, computer, and network configurations, have revealed the potentials of cloud gaming as well as the critical challenges toward its widespread deployment For a future work we would like to further investigate the effect other network conditions such as packet loss and jitter have on the end users cloud gaming experience Cloud gaming is a rapidly evolving technology, with many exciting possibilities One frequently mentioned is to bring advanced 3D content to relatively weaker devices such as smart phones and tablets This observation is made even more relevant by the fact that both Gaikai and Onlive are actively working on Android apps to bring their services to these mobile platforms However, recent large scale research indicates that it is not uncommon to find cellular network connections that have network latencies in excess of 200 ms [7], which alone may already cause the interaction delay to become too high for many games Seamless integration between cellular data connection and the lower latency WiFi connection is expected, and the switching to LTE may help alleviate the problem Other potential advancements involve intelligent thin clients that can perform a portion of the game rendering and logic locally to hide some of the issues associated Page 38 Distributed System Report with interaction delay, or distributed game execution across multiple specialized virtual machines [8] This will likely require creating games specifically optimized for cloud platforms Besides software and service providers, hardware manufacturers have also shown a strong interest in cloud gaming, and some have begun working on dedicated hardware solutions to address the prominent issues of cloud gaming NVIDIA has just unveiled the GeForce grid graphical processor, which is targeted specifically towards cloud gaming systems [9] It is essentially an all in one graphical processor and encoding solution The published specification shows that each of these processors has enough capability to render and encode four games simultaneously NVIDIA’s internal tests show that it can significantly mitigate the latency introduced in current cloud gaming systems [10] It is widely expected that this type of specialized hardware will usher in a new generation of cloud gaming REFERENCES [1] Jansen, W., & Grance, T (2011) Guidelines on security and privacy in 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CLOUD GAMING I INTRODUCTION The wide-used of the cloud computing has led the gaming industry to a revolution that changes the way human play games This up-and-coming technology called cloud gaming, ... altered in gaming industry to adjust the development of cloud gaming Cloud gaming is an innovative application that offers new opportunities for both upcoming and existing games based on cloud computing

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  • CLOUD GAMING

    • I. INTRODUCTION

    • II. OVERVIEW

    • III. ISSUES AND CHALLENGES

      • A. Interaction Delay Tolerance

      • B. Video Streaming and Encoding

      • C. Security

    • IV. CLOUD GAMING FRAMEWORK

    • V. CLOUD GAMING PLATFORMS

      • A. System Integration

      • B. Quality of Service Evaluations

      • C. Quality of Experience Evaluations

    • VI. OPTIMIZING CLOUD GAMING PLATFORMS

      • A. Cloud Server Infrastructure

      • B. Communications

    • VII. REAL WORLD PERFORMANCE: ONLIVE

      • A. Measuring Interaction Delay

      • B. Measuring Image Quality

    • VIII. COMMERCIAL CLOUD GAMING SERVICES

    • IX. A CASE STUDY ON CLOUD GAMING

      • A. System Architecture

      • B. The 2005 Software and Business Model

      • C. Changes in the Software and Business Model

      • D. Lessons Learned

    • X. SOME POPULAR CLOUD GAMING SERVICES IN 2019

      • A. Free Cloud Gaming

      • B. 5 of the Best Cloud Gaming Services [106]

    • XI. CONCLUSION AND FURTHER DISCUSSION

    • REFERENCES

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