Use VLANs to limit Multicasting

It should work, but you need to keep in mind that if there is a device that listens to traffic from both cameras, then it must be capable of participating on multiple VLANs. Also, typically (although it doesn't have to be that way), a VLAN corresponds to an IP subnet, so this might affect the way you assign addresses in the network. Finally, if you do have a device listening to multiple cameras, the port that goes to that device would most likely have to be tagged. Basically, what you want to do can be done, but there are lots of gotchas you need to be aware of.

Anoop

(snip)

As multicast was mentioned I would presume the use of IP multicast addresses. Probably comp.protocols.tcp-ip would be a better group for the IP specific part of the question.

-- glen

Note that switches can be L2 and therefore not perform the proper IGMP per se. But sometimes, they can do what's called "IGMP snooping." If they do this, then they will not flood L2 multicast frames to all of their ports. Only to those ports which are necessary to reach the IP multicast end systems.

Creating VLANs for every camera might be possible, although that depends on where the destinations are, whether they are likely to move, etc. I'm not sure how this would be set up.

Bert

yes. but the 1st Q is - do you care?

say your cameras are doing something fairly high quality - maybe 5 to 15 Mbps MPEG2?

with 10 cameras on a 100 Mbps LAN, then you have 50 Mbps of load (50%)

unless the cameras dont like the background traffic it is going to just work.

These switches do support VLANS. Could I create a VLAN

you could, but that implies all your traffic flows go to the central switches without any local flows - which might be a bit limiting if you have users mixed in with the cameras.

and the 2nd Q - if you have all these cameras, lots of traffic, then why not just replace the switches with something that does do IGMP snooping?

IGMP capable switches are not going to be expensive compared to good IP cameras.....