Is such, there is a tp company - the link exchange at the time of multicast, a single port multicast can reach 8 mbit, two ports when added up to no more than 4 mbit, good drop significantly more, multi-channel video of time that can not be multicast, and multicast data over 8 m ping gateway sudden rise to hundreds of ms, because more and more, the higher the ping
If correlates with a single switch on virtual local area network can be normal multi-channel multicast, increased data also won't appear the condition of high ping