Multicast vs Unicast for L2

[ATagliani]

Hi All,

Question - In regards to Multicast for like IP Security Cameras, would enabling Multicast help/lower for both bandwidth and viewing? 

Basically the setup we have is some video stuff all on 1 (the same) VLAN but spread out on multiple L2 4507s that connects thru to a L3 Nexus 7010 Core to each other (It's like an extended star topology). The video streams will all be on the same VLAN, and no routing between other VLANs is required.

I am being told that if it's in the same VLAN, then Multicast should not be needed.

Is this true? 

I personally think that might not be true especially if the vender programs their camera stuff for it or they are having bandwidth issues.

I would think that it would at least help with the trunks for bandwidth consumption if multicast is enabled.

Is this correct?

They are having issues with choppiness when 1080P is enabled but gets better when 720P is enabled. They are asking if I can enable Multicast on the switches to  help have the 1080P back without choppiness.

Please advise.

Thank You

[Reza Sharifi]

Hi,

Usually for Cameras services multicast is required regardless of all devices being in one vlan or multiple.

HTH

[ATagliani]

Thanks so would the Nexus L3 Core also need the multicast on it as well because the switches go through it to reach others in same vlan? 

[Reza Sharifi]

If they are all in the same vlan you just need IGMP snooping on all devices.  If the source and the the servers reside in different vlans than you also need to enable PIM on the SVIs.

Nexus devices usually have IGMP snooping enabled by default for all vlans.

HTH