Supporting IPTV In Fanout-free Switch Fabirc

IPTV not only breaks through the distribution pattern of traditional television but also innovates in the manner and the efficiency of obtaining, spreading and utilizing information and offers a vital opportunity to develop information communication technology industry. In the perspective of both the demand of terminal users and the development requirement of information communication technology industry, IPTV embodies the mode of application leading the development of network, and destines to be one of the primary services in the future internet.At present, since the performance of current border network can not meet the controllable, manageable and operateable requirements of operators about IPTV, "High Performance Broadband Information Networks" (3Tnet) of the National High-Tech Research and Development Program of China (863 Program) launches the project of "System performance and key technologies research on the access and convergence router (ACR)". In order to support IPTV, ACR needs the kind of switch fabric which can support IPTV; however, the switch fabric of ACR can not be developed via reserving redundant resource for multicast processing because IPTV will produce a great deal of multicast communication. The support of IPTV will cast great impact on the performance of ACR, so how to develop the switch fabric which can support IPTV becomes the key problem in ACR. For this reason, this thesis devotes its research effort to the kind of switch fabric which can support IPTV.As for a switch fabric, the support of IPTV is not just the same as the support of multicast but needs to satisfy the requirements of quality of experience guarantees. For this reason, the state-of-the-art multicast switch fabric models, including copy multicast, fanout multicast and bounded copy multicast, can not provide clear solution for the design of switch fabric which can support IPTV. Along with a deep investigation made into the transmission process of IPTV, the characteristic of TV data arriving at a switch fabric is found out. On this basis, a new scheme of switch fabric model, named as fanout-free switch fabric, to support IPTV is proposed, which originates from the working style of the ideal output queued switch fabric. Concretely, the scheme of Fanout-free switch fabric is built on such principle that if there is no data in the queues of any input port of a switch fabric, that means all of the data arriving at the switch fabric has been processed and transmitted into the queues of output ports; moreover, no matter how the number of either input ports or output ports varies, the factor of either speedup or link dilation needed to achieve the state of that there is no data in the queues of any input port holds its own; where after, output ports take the responsibility to drain TV data out of the switch fabric at an appropriate rate so as to satisfy the requirements of quality of experience guarantees of IPTV.Subsequently, this thesis introduces a kind of space division expansion fanout-free switch fabric, in which arriving unicast data is switched and transmitted to output ports by crossbar; and in parallel, arriving TV data together with other multicast data of non-TV services such as video conference, distance education and telemedicine are copied and transmitted to the destined output ports by multicast module. And then, space division expansion fanout-free switch fabric is thoroughly discussed from the aspects of its architecture, operating process, design of each component, scheduling model and scheduling algorithm. Furthermore, quantitative analysis is achieved via the method of the fluid model theory, and the simulation is carried out which demonstrates that the performance of space division expansion fanout-free switch fabric can satisfy the requirements of quality of experience guarantees. Both the result of the quantitative analysis and the simulation prove that fanout-free switch fabric can support IPTV.In order to provide more feasible solutions, other two kinds of fanout-free switch fabric, called as time division multiplexing fanout-free switch fabric and combined space and time division fanout-free switch fabric, are proposed on the principle of time division multiplexing mode and on the principle of combined space and time division mode respectively. Likewise, such aspects as the architecture, operating process, scheduling model, scheduling algorithm and performance of both kinds are thoroughly discussed. Without multicast module, time division multiplexing fanout-free switch fabric relies on the crossbar to process either unicast data or TV data and other multicast data of non-TV services in different time phases. However, as for combined space and time division fanout-free switch fabric, not only the multicast module deals with TV data and other multicast data of non-TV services but also the crossbar processes either unicast data or TV data and other multicast data of non-TV services in different time phases.The proposals of space division expansion fanout-free switch fabric, time division multiplexing fanout-free switch fabric and combined space and time division fanout-free switch fabric provide various practical solutions to design and implement the switch fabric of ACR. According to the demand of ACR, this thesis uses the scheme of fanout-free switch fabric to develop the switch fabric module of ACR. Via a detailed analysis of the switch fabric module of ACR from such aspects as design, the selection of chips and hardware implementation, this thesis gives an explicit explanation about how to design and implement the switch fabric module of ACR based on the scheme of fanout-free switch fabric.