Abstract | Multi-rate multicast schemes can be broadly classified
into two categories. In layered multicast, a video file is
transmitted by a base layer, which contains the most important
features of the video. Additional layers, called enhancement
layers, contain data that refine the quality of the base layer. In
simulcast, the video file is transmitted by replicated layers that
contain the same content at different quality. The benefits of
layered multicast versus simulcast are still under question, as
layered multicast presents higher complexity and more
challenging deployment than simulcast. In this paper, two multirate
multicast control schemes are compared. The layered
multicast SMCC congestion control against our proposed
solution for simulcast transmission, named ASSP. We compare
the two schemes under a controlled simulation environment
with the network simulator software (ns-2) by taking into
account the evaluation criteria in RFC 5166. The results
demonstrate that both SMCC and ASSP are TCP-friendly while
SMCC seems to suffers from small oscillations of the
transmission rate. In network topologies with low complexity
ASSP consumes no more bandwidth than SMCC for the
transmission of the different simulcast streams, while being a
simpler solution than the more complicated SMCC.
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