# Reliable User Datagram Protocol as a Solution to Latencies in Network Games
## 2 Related Research  
It has been a long time since the popularity of multi-player network-oriented games has languished while gamers' interest has widely shifted to the massive multi-player online games (MMPOG)/MMORPG. A proxy-based gaming architecture was proposed by [PERSON] [1] who attempted to distinguish types of gaming traffic based on the urgency or relevance of each traffic type. This was to deal with the issues involved in scalability. Another similar architecture was proposed by [2] which was to reduce the traffic strain on the central game server. The average load on this server depends on the number of participating users has been compared, with [3] suggesting that peer-to-peer architecture effectively relieves stress (load) on the server, allowing a lower latency level than the fully centralized architecture of the server. Despite such merits, this architecture may not deal effectively with the inherent problems of state inconsistency resolution. Hence, the central arbiter architecture that assumes a hybrid role between the above two different architectures was proposed to take advantage of both strengths. During the past decade, a large number of studies were conducted to determine the negative aspects pertaining to jittering, delays, and packet losses in multi-player games or wireless games [4; 5; 6; 7; 8; 9; 10] based on the simulations. Some of them have focused on the implementation of the test bed environments, especially for wireless games [11; 12; 13]. One recent survey [14] clearly shows that network latency is one of the most critical elements relevant to user satisfaction in wireless games. An improved Quality of Service (QoS) means a better game performance based on descriptions [15] where it is been proven that the Universal Mobile Telecommunications System (UMTS) exhibits a better performance level in interactive real-time games than that of General Packet Radio Service (GPRS) as it, on some level, surmounts the problems of overprovisioning which often cause delays and jittering during the game process. It was suggested that statistical multiplexing and QoS together ensure an improved multiple game flow. More wireless gaming architectures have been introduced in recent years [16; 17; 18]. However, some of the present global leading wireless game providers are focusing on implementing their services on Enhanced General Packet Radio Service (EGPRS) that could be well-suited for the cross-layer design proposed in this study. Producing or launching wireless games with a reduced overhead is one of the major considerations which game providers should not take lightly as it would be costly to change the existing protocol stack for the intermediate nodes not connected to the game being played. Currently, either UDP or R UDP are often used for games [19], with the latter usually playing the role of continuously delivering the status of the current gaming information and also being suitable for lightweight game packet delivery. On the basis that TCP is a relatively slow protocol because of its complex congestion control algorithms and byte-oriented window scheme, this is considered a protocol that is not suited for wireless online games that accommodate multiple numbers of users simultaneously without causing delays. In addition, TCP cannot even deal with moderate traffic congestion when delivering packets and this makes it quite clear that it is not at all suitable for MMPOG games. The connectionless protocol UDP, however, operates on the top of the IP layer and exchange data directly and recovers data when necessary, which seldom happens. As both are universal protocols widely adopted for most network devices and equipment, they are quite convenient for application developers. R UDP supplements UDP's error recovery function through a one-time acknowledgment scheme. Currently, both UDP and R UDP have become a major default protocol for wireless gaming infrastructures [20].