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The final publication is available at Springer via http://dx.doi.org/10.1007/s11042-011-0841-y ; FEC (Forward Error Correction) mechanisms improve IP content transmission reliability through the recovery of packets lost in transmission. Opposite to ARQ (Automatic Repeat Request), FEC mechanisms are especially suited to unidirectional environments or to multicast environments where multiple receivers perceived different channel losses, thus making difficult the implementation of mechanisms based on feedback information. Among the different types of FEC codes, this paper presents a thorough performance evaluation of LDPC (Low Density Parity Check) codes, based on an implementation developed by the authors, according to the specifications defined by RFC 5170 for the usage of LDPC codes by push content applications based on the FLUTE protocol. LDPC codes provide a good trade-off between performance and complexity, hence, they are appropriate for mobile applications. Contributions of this paper include tests conducted with commercial mobile phones connected to the push content download server over a Wi-Fi network. The evaluation highlights the advantages of using packet level FEC encoding in file transmission over unidirectional networks and provides with a comparison between two kinds of LDPC structures: Staircase and Triangle. This is accomplished by calculating the inefficiency ratio of these LDPC structures in different environments. Results show that the implemented LDPC codes can provide inefficiency ratios close to one when the different coding parameters (as the code rate or the number of blocks) are configured to an optimal value that depends on the packet loss rate. © 2011 Springer Science+Business Media, LLC. ; This work was supported in part by the Ministry of Industry, Tourism and Trade of the Government of Spain, under project "Redes Hibridas para la Provision de Servicios Turisticos" (TSI-020302-2010-165). ; De Fez Lava, I.; Fraile Gil, F.; Belda Ortega, R.; Guerri Cebollada, JC. (2012). Performance ...

669 688 60 3 ; S ; The final publication is available at Springer via http://dx.doi.org/10.1007/s11042-011-0841-y FEC (Forward Error Correction) mechanisms improve IP content transmission reliability through the recovery of packets lost in transmission. Opposite to ARQ (Automatic Repeat Request), FEC mechanisms are especially suited to unidirectional environments or to multicast environments where multiple receivers perceived different channel losses, thus making difficult the implementation of mechanisms based on feedback information. Among the different types of FEC codes, this paper presents a thorough performance evaluation of LDPC (Low Density Parity Check) codes, based on an implementation developed by the authors, according to the specifications defined by RFC 5170 for the usage of LDPC codes by push content applications based on the FLUTE protocol. LDPC codes provide a good trade-off between performance and complexity, hence, they are appropriate for mobile applications. Contributions of this paper include tests conducted with commercial mobile phones connected to the push content download server over a Wi-Fi network. The evaluation highlights the advantages of using packet level FEC encoding in file transmission over unidirectional networks and provides with a comparison between two kinds of LDPC structures: Staircase and Triangle. This is accomplished by calculating the inefficiency ratio of these LDPC structures in different environments. Results show that the implemented LDPC codes can provide inefficiency ratios close to one when the different coding parameters (as the code rate or the number of blocks) are configured to an optimal value that depends on the packet loss rate. © 2011 Springer Science+Business Media, LLC. This work was supported in part by the Ministry of Industry, Tourism and Trade of the Government of Spain, under project "Redes Hibridas para la Provision de Servicios Turisticos" (TSI-020302-2010-165). De Fez Lava, I.; Fraile Gil, F.; Belda Ortega, R.; Guerri Cebollada, JC. (2012). ...

[EN] This paper presents and evaluates a system that provides TV and radio services in mobility using 4G communications. The system has mainly two blocks, one on the cloud and another on the mobile vehicle. On the cloud, a DVB (Digital Video Broadcasting) receiver obtains the TV/radio signal and prepares the contents to be sent through 4G. Specifically, contents are transcoded and packetized using the DASH (Dynamic Adaptive Streaming over HTTP) standard. Vehicles in mobility use their 4G connectivity to receive the flows transmitted by the cloud. The key element of the system is an on-board proxy that manages the received flows and offers them to the final users in the vehicle. The proxy contains a buffer that helps reduce the number of interruptions caused by hand over effects and lack of coverage. The paper presents a comparison between a live transmission using 4G connecting the clients directly with the cloud server and a near real-time transmission based on an on-board proxy. Results prove that the use of the proxy reduces the number of interruptions considerably and, thus, improves the Quality of Experience of users at the expense of slightly increasing the delay. ; This work is supported by the Centro para el Desarrollo Tecnologico Industrial (CDTI) from the Government of Spain under the project "Plataforma avanzada de conectividad en movilidad" (CDTI IDI-20150126) and the project "Desarrollo de nueva plataforma de entretenimiento multimedia para entornos nauticos" (CDTI TIC-20170102). ; Arce Vila, P.; De Fez Lava, I.; Belda Ortega, R.; Guerri Cebollada, JC.; Ferrairó, S. (2019). Proxy-based near real-time TV content transmission in mobility over 4G with MPEG-DASH transcoding on the cloud. Multimedia Tools and Applications. 78(18):26399-26425. https://doi.org/10.1007/s11042-019-07840-6 ; S ; 26399 ; 26425 ; 78 ; 18 ; 3GPP (2012) Requirements for Further Advancements for E-UTRA (LTE-Advanced), Sophia-Antipolis Cedex, France, TR 36.913 V8.0.0, Release 11 ; 3GPP (2013) Universal Mobile Telecommunications ...

26399 26425 78 18 ; S ; [EN] This paper presents and evaluates a system that provides TV and radio services in mobility using 4G communications. The system has mainly two blocks, one on the cloud and another on the mobile vehicle. On the cloud, a DVB (Digital Video Broadcasting) receiver obtains the TV/radio signal and prepares the contents to be sent through 4G. Specifically, contents are transcoded and packetized using the DASH (Dynamic Adaptive Streaming over HTTP) standard. Vehicles in mobility use their 4G connectivity to receive the flows transmitted by the cloud. The key element of the system is an on-board proxy that manages the received flows and offers them to the final users in the vehicle. The proxy contains a buffer that helps reduce the number of interruptions caused by hand over effects and lack of coverage. The paper presents a comparison between a live transmission using 4G connecting the clients directly with the cloud server and a near real-time transmission based on an on-board proxy. Results prove that the use of the proxy reduces the number of interruptions considerably and, thus, improves the Quality of Experience of users at the expense of slightly increasing the delay. This work is supported by the Centro para el Desarrollo Tecnologico Industrial (CDTI) from the Government of Spain under the project "Plataforma avanzada de conectividad en movilidad" (CDTI IDI-20150126) and the project "Desarrollo de nueva plataforma de entretenimiento multimedia para entornos nauticos" (CDTI TIC-20170102). Arce Vila, P.; De Fez Lava, I.; Belda Ortega, R.; Guerri Cebollada, JC.; Ferrairó, S. (2019). Proxy-based near real-time TV content transmission in mobility over 4G with MPEG-DASH transcoding on the cloud. Multimedia Tools and Applications. 78(18):26399-26425. https://doi.org/10.1007/s11042-019-07840-6 3GPP (2012) Requirements for Further Advancements for E-UTRA (LTE-Advanced), Sophia-Antipolis Cedex, France, TR 36.913 V8.0.0, Release 11 3GPP (2013) Universal Mobile Telecommunications System (UMTS); ...

This paper describes how FLUTE (File Delivery over Unidirectional Transport) and DASH (Dynamic Adaptive Streaming over HTTP) can be used to provide mobile video streaming services over broadcast wireless networks. FLUTE is a multicast protocol for multimedia file download. In this proposal, the protocol is adapted to provide video streaming services in crowded environments. Thus, video is delivered over a single connection to all viewers, reducing the traffic in the network. FLUTE incorporates an AL-FEC (Application Layered Forward Error Correction) mechanism in order to improve the reliability of the broadcast communication channel. For streaming applications, AL-FEC improves the relationship between the PSNR (Peak Signal-to-Noise Ratio) of the received video and the bandwidth allocated to the broadcast connection. The AL-FEC hereby presented applies simple unequal error protection schemes to favor the download of key frames. Furthermore, the proposal is based on the same video segmentation mechanism as DASH and therefore, clients can connect to a DASH repository to repair errors in the segments. This paper shows that FLUTE and DASH can be seamlessly integrated into a hybrid broadcast/unicast streaming technology, providing flexibility to trade off PSNR and bandwidth depending on the conditions of the mobile network. ; This work was supported by the 11012 ICARE (Innovative Cloud Architecture for Real Entertainment) project within the ITEA 2 Call 6 Program of the European Union. ; Belda Ortega, R.; De Fez Lava, I.; Fraile Gil, F.; Arce Vila, P.; Guerri Cebollada, JC. (2014). Hybrid FLUTE/DASH video delivery over mobile wireless networks. Transactions on Emerging Telecommunications Technologies. 25(11):1070-1082. doi:10.1002/ett.2804 ; S ; 1070 ; 1082 ; 25 ; 11 ; ETSI TS 126 346 v11.3.0. Universal Mobile Telecommunications Systems (UMTS); LTE; Multimedia Broadcast/Multicast Service (MBMS); Protocols and Codecs 2013 ; Lecompte, D., & Gabin, F. (2012). Evolved multimedia broadcast/multicast service (eMBMS) in ...