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Efficient streaming of bandwidth intensive and delay sensitive multimedia contents over error prone wireless links has proven to be one of the most challenging problems of the current era of digital communication. However, applying Unequal Error Protection (UEP) strategies at application layer and avoiding unnecessary packet discard at MAC layer yield valuable outcomes and can be incorporated to address the challenge. In this article, we have proposed the idea of discriminating classified video streaming calls from the data packeting over an IEEE WLAN link through bit demarcation in network packet headers, where remarkable concept of UDP-Lite deployed at the transport layer further assists in UEP implementation of the inevitable video parts later on MAC layer. In this way, error computation at various network levels are evaluated and disabled in order to attain increased throughput characterized by the higher number of packets available for decoding, enhanced multimedia visual quality due to gap elimination (appears as a consequence of some frame loss), efficient utilization of link bandwidth with no re-transmissions and reduced delays with least error checksum computations and packet re-transmissions. Promising experimental outcomes have been shown in tabular and graphical forms, particularly represented through subjective assessment of the reconstructed video clips with an emphasis on viewer QoE (Quality of Experience).

Efficient streaming of bandwidth intensive and delay sensitive multimedia contents over error prone wireless links has proven to be one of the most challenging problems of current era of digital communication. Applying unequal error protection strategies and avoiding unnecessary packet discard at various network levels yield valuable outcomes. In this article, we have proposed the idea of discriminating classified video streaming calls from the data packeting over IEEE WLAN through bit demarcation in network packet headers. Error computation at various network levels are evaluated and disabled in order to attain increased throughput characterized by the higher number of packets available for decoding, enhanced multimedia visual quality due to gap elimination (appears as a consequence of some frame loss), efficient utilization of link bandwidth with no re-transmissions and reduced delays with least error checksum computations and packet re-transmissions. Moreover, collaborative estimation of various layers parameters results in proficient selection of streaming parameters like group of picture structure, inter spacing of anchor frames, constellation coding and signal power. The proposed system will be helpful in future information and communication systems by providing reliable video streaming over wireless.

Error prone wireless channel induces error bursts in transmitted data frames and renders the frames unable to be decoded. Prevalent error control techniques work to combat the error effect through pre- or post- transmission control measures like FEC, ARQ, HARQ etc. All of these techniques induce some sort of processing and retransmission delay in net transmission duration. On other hand, applications transmitting multimedia contents and especially video contents are highly delay sensitive and exhibit hard real time requirements. However, a little degradation in quality of reconstructed video frames can be compromised for better throughput and minimized time delays. The idea of trade off between video quality and throughput has been proposed in this paper; implemented through a +modification to IEEE 802.11 frame format such that certain fields are marked to designate a frame as a video frame. Such designated frames are proposed to be treated differently from normal data frames in order to enhance video throughput and reduce transmission time delay. Results achieved are quite promising; although video frames with high motion contents possess degraded signal quality but perceptually the results seem satisfactory.

In recent research, estimations for condition of channels are based on either (i) physical layer parameters (e.g. SNR, RSSI etc.) or (ii) statistics of transmitted data (e.g. no of retransmissions, throughput etc.). Our research evaluates that depending upon one approach entirely while ignoring other can lead to loss of valuable information about adaptation of rate to send data. This in turn can highly degrade throughput. In view of this, the proposed scheme, RBSRA, defines channel assessment as the function of combining PHY layer parameter with statistical metrics. RBSRA estimates accurate assessment of fluctuating channel conditions, so it leads to the substitution of data rates to yield higher throughput. RBSRA uses, the PHY layer parameter RSSI in cooperation with the statistical metric that is number of received ACK, in such a way that it avoids unnecessary fluctuations in data rates and provides more realistic selection amongst the available link speeds. Performance of RBSRA depicts that the data rate selection has been precisely synchronized with ups and downs of the channel conditions along with statistics of transmitted stream.

Researchers have shown considerable interest in TCP variants and their behavior under different traffic conditions by conducting research on congestion management of TCP in IP supporting networks. TCP provides a trustworthy end-to-end data transfer under changeable wired networks. To overcome the problem of unreliability of IP network, TCP is used. Many service providers are now moving to MPLS over Inter- net to transfer data, preferring it over traditional transferring strategies. Different variants of TCP show varying behavior in best effort Internet Protocol networks. This paper presents an extensive investigational study of TCP variants under IP and MPLS networks by focusing Tahoe, Reno, New Reno, Sack and Vegas under File Transfer Protocol (FTP).

In a multi-camera setup, inter-sensor statistical redundancy should be eliminated most significantly to achieve higher compression efficiency. This consequently saves the required bandwidth for the resultant piece of information coming out of a camera sensor network. In this research work, Moving Picture Expert Group (MPEG) a video compression standard has been extended to eliminate inter-sensor statistical redundancy for a multi-camera setup. For the formulation of results from all aspects, two strategies have been designed for inter-sensor communication. Moreover system is designed to work under two working modes (named as Scenario-A and Scenario-B). Results formulated in graphical formats show the system performance for both communication strategies under both working modes. Overall system performnace higher compression gains are obtained at lower bitrates.

Energy awareness is an essential design issue in wireless sensor networks (WSN). The routing techniques of WSN are classified into three main categories Data-Centric, hierarchical and location-based. Data-Centric technologies perform in-network aggregation of data to yield energy-efficient dissemination; Sensor Protocols for Information via Negotiation (SPIN) and Directed Diffusion (DD) are basic Data-Centric routing protocols. This paper presents a survey on Data-Centric routing and specifically focuses on the Directed Diffusion and its variants (dissemination and aggregation variants) and the protocols that follow the similar concept like Directed Diffusion.

As the demands of the handheld devices and pervasive services are increasing, the issues of security have alarmingly risen. One can wonder about the pervasive services to be free of every security flaw. The paper suggests a mechanism for a trust based ad-hoc authentication with a distributed trust based mechanism and defined security policies related to access control for pervasive devices. The openness of a true pervasive environment has been encountered with the interaction history and recommendations. The architecture is designed to provide secure autonomous services for an assumed pervasive based scenario. The nature of pervasiveness is satisfied by allowing the novel user to proceed in the system but with the minimum trust initially, which changes dynamically depending on the actions which the user performs. It secures the privacy of the user by the implementation of security policies in the Security Manger(SM) in order to gain final access to the service.