Technology

Video Streaming Within a Wireless Environment
Introduction
There are a number of new developments in the wireless multimedia communication industry. One such development is the usage of video streaming within a wireless environment. The core aim of this new invention is to enhance speed, efficiency, and effectiveness in the telecommunication industry through the use of the various Internet technologies that are in existence. Video streaming entails the capability of a video being downloaded to a computerized machine while at the same time being played yet not interfering with the quality of the video. This paper analyses, from a technological point of view, various issues related to video streaming and wireless technology as a form of multimedia communication (Cherriman, Keller, and Hanzo 1997). The new wireless multimedia communication systems are based on the hierarchical modulation, which gives unequal transmission reliability that corresponds to the sensitivity and elimination of transmission errors.

Overview of Video Streaming
Video streaming refers to the real time transmission of various stored videos either through wired or wireless technologies. This technology has very stringent bandwidth, loss requirement, and the need for certain delays to be dealt with. This implies that in video streaming, new protocols, router scheduling, and adaptation of output rate of the concerned video to the available bandwidth is enhanced (Phylip and Schaar 2004, pp. 25-67). Whenever streaming video, which is also called, streaming media, is used, a web user does not always have to complete file download in order to download it. Rather than wait for the completion of file download, the media is normally sent in continuous stream of the data and it is played immediately it is played. A player, a special program that is used to uncompress the sent video before the recipient can view and even listen to it, is normally used in by the recipient of the streamed video as indicated in figure two below (Fig. 2). The player used to play the streamed media could either be downloadable software from the software makers website or an integral section of the browser being used.

Major technologies used in the streaming media and the streaming video include the Real-System G2 which is from the Real-Network, VDO, and Windows Media players from the Microsoft corporation. The standard compression that is mainly used in streaming video compression algorithm technology includes MPEG and other codec programs. In most instances, Streaming video is normally sent from a prerecorded video files, though it can also be distributed as a section of a live broadcasting feed (Various Streaming Media journal 2010). A live broadcast, in most instances, is normally converted into a digital signal that is compresses and then transmitted from specialized web server that has the capability to transmit the same file to various users simultaneously.

Wireless Communication
Wireless communication does not necessary entail the total use of a non wired communication system but rather may combine both wired systems and the wireless capabilities in the transmission and receivership of the transmitted information. With regards to wireless streaming, wireless networks, WLANs, offer several challenges with regard to multimedia streaming. Dynamic variations in channel conditions due to noise, interference, and path loss effects impact data throughput and packet loss. There is also the need for dynamic alteration in the number of users in a given network with their varying data rate requirements resulting in a varying degree of contention and collision in the network impact the amount of bandwidth per user or per flow. Real-time adaptation at the media access control layer is required to adapt to the varying conditions (Yong and James 2005). The choice of a given multimedia transport layer such as the transport control protocol or the user datagram protocol is also of great concern in video streaming employed in a wireless communication environment. Multimedia applications have the ability to scale and adapt to varying wireless network conditions, which must also be considered and exploited (Sakamoto, et al. 1998, pp. 290-595). Currently, more than one hundred million videos can be watched over the Internet, thanks to the concept of wireless video streaming, a development in the wireless multimedia communication technology. International recognition is required in ensuring efficiency, compatibility and authenticity, and reliable communication in a wireless communication environment.

Multimedia and Video Streaming
Latest development in the multimedia communication has led to the need to combine a number of content forms in order to ensure faster and efficient delivery of data and information. Video streaming in a wireless environment entails utilization of relevant protocols. Through the use of the wireless streaming of videos, it has been made possible to play a section of a video while its section which may be located in a very far distance is being transferred. According to Dapeng, et al. (2001, pp. 11-32), Videos with sound, interactivity, text, still and moving images, video footages, and animated pictures are some of the common content forms that can be combined in a multimedia being transferred in a streamed multimedia format. There are a number of areas in which the latest development in the multimedia communication through the invention, development, and usage of video streaming in a wireless environment have been utilized. According to Phylip and Schaar (2004, pp. 120-241), the core areas of usage of this specific multimedia technology include real time commercial advertisements aimed at grabbing and keeping attention in the product being advertised fine arts and entertainment that entails usage of very unique and special effects in animations and fine art education industry in which video streaming has of late been used for real time computer based training and in distance learning educational system engineering in which collaborative training is undertaken by ensuring the software engineers fully collaborate with other professions in solving problems in real time and medicine where operations are demonstrated by one doctor on one end while others view the video being streamed in real-time and then performing the surgery and other form of treatment (Fig. 2). In most instances, the recipient of the video being streamed uses a program such as real player and media player to watch the video while the sender of the video uses a server through which he actually produces the streaming video.

Video Streaming Within a Wireless Environment
Interactive multimedia on wireless networks requires high bandwidth due to the data rates and payload size. One frequently cited wireless scenario has users conducting real-time, multimedia videoconferencing sessions over a wide-area wireless Internet connection. The wireless client is highly mobile within an enterprise campus or dense city limits and shares very media rich presentation with multiple parties that are dispersed in different connectivity scenarios (Cherriman, Keller, and Hanzo 1997). The user experiences a high degree of QoS supporting the multimedia session and presentation delivery, regardless of ones movement or the locality. In order for this scenario to occur, multiple effects including time varying channel conditions, local or remote congestion conditions, and the end-to-end QoS requirements is matched with an adaptive application capable of offsetting the limitations of the network. This, in video streaming in a wireless environment, is done by managing latency, reliability, and the throughput degradations while at the same time hiding the user from the underlying mobility and complexity issues and the degraded QoS in a wireless environment.

In order to ensure efficiency of operation of the streaming media, WLAN technologies that include 802.11 and Wi-Fi are used in order to ensure proper working within a range of the order of one hundred meters. The MIMO based wireless LAN technologies uses various antennas with the core aim of increasing the throughput which comprises of additional capability to trade off the increased range. This helps to enhance increased throughput. Technologies such as the reliable output of multiple input multiple can also be applied to other wireless technologies related to video streaming (Yong and James 2005).

Although the WLAN protocols, which are also commonly referred to us 802.11abgn protocols, are expected to be the predominant technology for the wireless access in an enterprise, there is reconfiguration in the modern systems hence the achievement goal of ensuring that the systems are fully compatible with  the video technology. WiMax facilitate the use of video streaming concepts in a wireless environment since it has a range in the order of several kilometers, Bluetooth, and ultra wideband technologies that are used for short distances with the UWB technology enabling high data rate wireless transmissions over short distances. Cellular technologies are also organized and fully optimized for video traffic, and are aimed at supporting very long range that are targeted at lowering data throughput compared to the Wi-Fi based technologies. For instance, the network management and administration techniques used in cellular networks may be applicable in the WiMax and techniques used in wired networks such as local area network (Sakamoto, et al. 1998, pp. 290-595).

On the other hand, seamless transfer of multimedia sessions or VoIP protocol calls between such networks, though being challenging tasks to achieve, have positively contributed to ensuring that video streaming is fully achieved and becomes very practical in most wireless environment.
WLANs offer several challenges with reference to the video streaming in a wireless environment. Dynamic variation in channel conditions due to noise, interference, and path loss effects impact data throughput and packet loss. Additionally, dynamic changes in the number of users in the network with their varying data rate requirements resulting in a varying degree of contention and collision in the network impact the desired amount of bandwidth depending on the user or based on the flow. To attain real-time adaptation at the MAC layer which is needed in the streaming media within a wireless environment, varying conditions ought to be adapted. The choice of the transport layer, as the best available alternative for use as the transport control protocol, is of great concern. Multimedia applications used in this specific newly developed have the ability to scale down and even adapt to varying wireless network conditions, which should be considered and exploited.

Multiple transmitting antennas can help increase the data rates in the same channel. Multiple receiving antennas help in enhancing efficient recovery of the transmitted data. Multiple antennas also facilitate the increase of the range and reliability of data transmitted in a channel without an increase in data rates. Multiple antennas are used to increase the data rates using a number of antennas. This is attained by transmitting data to a number of channels in a simultaneous manner. Using two transmit a throughput of 108 Mbps in a 20 MHz channel is realized. Using a wider 40 MHz channel, and not the commonly known 20 MHz channel, help t o increase the throughput to 216 Mbps. Dapeng, et al. (2001, pp. 211-275) argues that the usage of about four transmit-antennas helps to increase even further to four hundred and thirty two megabits per second. Additional multiplexing sub-channels for the multiplexing division and the use of much newer coding schemes, such as the very low density parity check which help to increase the actual throughput to more than five hundred megabits per second in the future of wireless local area network video streaming technologies. This improvement has been pursued in the overall physical layer capacity using the 802.11n standard.

Even though wireless communication generally faces a number of challenges, video streaming in a wireless environment ensures that more attention is accorded to the likely challenges due to the high cost of failure that may be involved in instanced where by poor planning and organization has been witnessed. Cherriman, Keller, and Hanzo (1997) believe that the weak signals, crowded airwaves, and multipath fading tend to derail the efficiency and effectiveness efforts done. However, unique compression techniques have led to various challenges being sufficiently addressed. In the modern world, in order to fit a given streaming video application to an available wireless bandwidth, H263 and MPEG-4 are used to efficiently compress the video and ensure that its quality is kept intact throughout the uploading, transmission, and downloading process. The compression helps in the delivery of the video bit streams. The quality of the video in the development of this communication technology does not compromise on the quality of the video and its other properties at the expense of the bandwidth as has previously been the case.

Protocols in the Two Relevant Layers
The MAC Layer
Real time streaming protocols are used in an attempt to ensure high and better quality of the video being delivered. Unicast protocols are normally employed in ensuring efficient delivery of the video from the server station to the recipient. To reduce data replication, multicast protocols are employed. Video streaming uses the application layer QoS and it greatly affects the users perceived presentation quality. Video streaming could use the standard web servers that are commonly used to deliver video contents hence the need to guarantee the delivery protocols such as the transport control protocol and the HTTP though this is not always optimal for the continuous media as illustrated in figure 1.

During the communication process using the wireless streaming video technology, the throughput located at the top of the media access control (MAC) is normally affected by various properties and issues. To begin with, the physical layer physical layer throughput depends on the PER that is located at the physical layer while the transmission time for each packet is a function of both the coding scheme and the modulation involved (Phylip and Schaar 2004, pp. 45-323). On the other hand, the overheads for the protocol timing such as the acknowledgement time and the interface spacing are put into consideration. The time that is spent in the random back-off counter and the actual duration for which the medium is kept busy without interfering with the transmission of other medium is considered together with the unused time that remains idle in the entire network. Retransmissions are attempted at the MAC layer in the absence of an acknowledgement. Packets may be in error if the acknowledgement is not received from the destination within a specified duration after transmission. Either the packet may be in error when it reaches the destination or the return acknowledgement might itself be in error. In both cases, a packet is retransmitted by the MAC, as long as the retry-limit is not reached. During retransmissions, link adaptation may be performed to attempt sending a packet in a more robust modulation and coding scheme.

Real Time Streaming Protocol
Real-time video streaming has emerged a very central and crucial service in various telecommunication industries. The usage of the wireless systems to facilitate better video streaming is therefore a very central factor in ensuring efficiency, effectiveness, and reliability in the communication process in multimedia. The real-time video streaming protocol enables efficiency and effectiveness in the communication process while at the same time ensuring minimal or no interruption occurs in the communication process. Streaming video servers use this protocol in delivering the media being transferred (Cherriman, Keller, and Hanzo 1997). The RTSP normally enable proper control of various multimedia video streams that needs to be delivered. However, the actual task of transmitting the streaming video does not solely lie on the RTSP protocol but rather entails coordination and integration of other wireless protocols that is aimed at enhancing speed and accuracy in the video transfer process.

Systems Architecture for Wireless Multimedia Scalability
To support an end-to-end and a node-level systems orientation to scale and adaptation of wireless multimedia, the end-to-end wireless multimedia scalability principle in network control ought to be covered. In accordance to the journal on the Various Streaming Media (2010), the ability of applications to adapt to positive or negative changes in wireless conditions, by either leveraging in-network services or binding alternative node-level, inter-layer optimizations, gives video streaming applications much flexibility in managing real-time and media adaptation within most wireless environments. Tighter automation of application control, layer integration, and bandwidth management is reinforced in order to ensure that effectiveness in the way of operation of streaming media. However, the applications adaptation flexibility in video streaming within a wireless environment depends on its ability to detect or even respond on a faster time-scale.

In small scales, broadcasting and at times multicasting system-level of information in a smaller-scale are used with very tightly coupled networks and even direct exchange of information between the nodes with information propagation. Such system-wide proactive adaptation and management of resources real-time ensure that the system is made much aware and resilient to dynamically varying constraints. Consequently, this ensures that the impact of worsening conditions is minimized and that the best option is undertaken. Additionally, video streaming in a wireless environment uses a direct peer-to-peer transmission model after the establishment of proper contact between the peers. In some instances where a more direct peer-to-peer wireless link that is more reliable and efficient is required, communication between the peers is always established (Cherriman, Keller, and Hanzo 1997). Furthermore, multiple hops are at times utilized over relatively short distances in order to reduce the existing packet errors because of the necessitated path loss over large distances within a wireless links.

In wireless video streaming multimedia communication technology, hops over the same frequency channel normally cause contention. The contention ultimately reduces the size of the available bandwidth. In multi-hop networks, that also support video streaming in a wireless environment both exposed nodes and the hidden ones are great issues of concern. For efficiency and effectiveness in the video streaming undertaken in a wireless environment, network configuration between two endpoints could vary dynamically. The variations are dependent on the varying network conditions, mobility, or other constraints in the system. QoS policy or state information exchange through intermediate nodes is vital in meeting the end-to-end requirements. In large wireless ad-hoc networks, routing tables with link information grow significantly in size. This information includes link quality information as perceived at the MAC physical layer of a communication wireless network node. To achieve scalability in this lately developed multimedia technology, nodes only store the local information about nearby links. The information stored in a distributed fashion is then propagated through nodes on request, in order to adequately understand the end-to-end performance within a communication path that lies between two endpoints in a given. The response time of adaptation mechanisms at the nodes based on these dynamically varying conditions normally determine how proactive and effective the adaptation mechanisms used are. This generally helps in ensuring that any variation in the quality of the received multimedia transmissions is imperceptible to the desired user.

Streaming Of Video over a Wireless LAN Multicast and Unicast
The latest development in the wireless multimedia communication has led to the increasing use of video streaming technologies within a wireless network. A local area network facilitate the use of video streaming, which is indeed a multimedia communication, in a LAN in order to facilitate faster and more reliable communication. This technological advancement may be used both in a single user case and as a multiple user case. In the single user case, various algorithms for the streaming video bit-stream get to be involved over a wireless LAN. Using the MDFEC trans-coding mechanism, prioritized multi-resolution bit-stream is converted to a non prioritized multiple description bit-stream. This method however demands a progressive video input for efficient and reliable communication of the video streaming technology. In the multiple user case, problem related to the multicasting of the video bit-stream over a wireless local area network is addressed. Different data packets that encompass the video being transferred over the wireless network are transferred to various users based on their request and their respective location. In instances where there is significant loss of packets, every user needs very significant replacement (Phylip and Schaar 2004, 56-218). Progressive video coding is used in order to ensure that in a wireless network, each users needs are fully addressed. For the Unicast scenarios that are normally modeled in this multimedia communication technology, the novel repeat request for the hybrid system is used to combine, in an efficient manner, the ARQ protocol with the forward error control (A Video Streaming and Hosting Services website). This clearly explains why the wireless LAN facilitates the operation of high bit rates in order to allow the transmission of much better quality video data.

Technical Problems of Wireless Video Streaming and the Possible Solutions
A number of technical problems that do not exist in wire-based systems are related to the concept of latest development in multimedia communication in which video streaming is undertaken in a wireless environment. One such problem relates to the fact that during the bad weather conditions, the receiver that may be high could lead to a loss rate. Additionally, the sender may be tempted to inaccurately assume that the network to be congested hence a decrease in the output rate. Ultimately, the quality of the video would be compromised. The major problems associated with streaming videos could effectively be associated with the inability of the receiver to fully distinguish between wireless packet losses and congestion. The other problem is that in most instances, the sender tends to associate and even estimate the state of the network that uses loss rate as a unique feedback parameter.

There are two alternative solutions to the problem associated with video streaming. One such solution to the problems is to ensure that only congestion related problems are reported. Additionally, only correlation of losses and delays should be reported. This can be achieved ensuring that the receiver only enables reporting of the loss rate due to the likely occurrence of congestion. In the need for reporting the correlation of the losses and delays in the media communication, the sender ought to ensure that they report the correlation between the delay and the packet loss curve.

Conclusion
Wireless network-based video transfer in the multimedia communication industry ensures much easier access through the use of streaming media. It has indeed been proved that streaming media causes drastic changes in the manner in which entertainment through multimedia communication, education, and other forms of mass media are undertaken. Streaming media, for instance, has been used in educational institutions to enhance knowledge sharing and increase cross-company cooperation. The fact that various media companies and individual are opening archives and offering access to monies and documentaries though wireless web capabilities explains the extent to which wireless multimedia communication has been transformed. Mobile phones and various careers are used in launching live television services for mobile phones in an attempt to fully exploit advantages related to video streaming in a wireless environment. This development in multimedia communication provides an easy access-on-demand of rich media anywhere through any device.