Replace copper with Fiber?

[Danny400]

So at the old motel I work at, we have a 8 port switch in the office, fully utilized, then another 8 port switch thats located 150ft away, connected via cat6 cable, then a cat6 cable to a Cisco switch -> Arris router. There is a lot of congestion with the 3 CCTV DVR's constantly broadcasting. If I replaced both 8port switches with a 16 port with 1Gbps SFP, and connected them via fiber instead of cat6, would that make a difference?

Thanks

[icecream-guy]

if they are connected at 1G copper and 1G fiber, no.
if they are connected at 100M copper and then 1G fiber, yes

[deanwebb]

If all the switches are cascaded off of each other, then it will make a difference, as you won't have to have all the traffic bound to a downstream switch clogging the one port heading to it. I'm all for getting rid of cascading switches.

But that would be true of copper 1G as much as for fiber. I wouldn't mess with fiber unless you've messed with it before and still have 2 good eyes. But seriously, not a lot of need to go to fiber if you're not in the datacenter environment.

[Dieselboy]

Digressing from the OP's original question; where's the congestion occurring? OR, how do you know that there is congestion?

The cameras -> DVD is probably unicasting rather than broadcasting. If each camera is 1080p over IP then you are probably looking at around 1.5mbps per camera unidirectional to the DVR system. A 1GB link is 125mbps so can support roughly 100 cameras sending moving pictures (h.264 codec uses compression so there's less bandwidth being consumed when the video does not have much movement).

That being said if the cameras really are broadcasting then they should be on their own VLAN else every device on the broadcast domain (subnet) will receive the video streams. So if you have say 10 cameras (1.5 * 10 = 15mbps) and some devices connected over 100MB link (100 / 8 bits = 12.5mbps) then you could saturate the 100MB connections with broadcast traffic and they'd stop working. Although I doubt this is really broadcasting anyway.

[Danny400]

Sorry for the late reply, I lost the url to the site.

Digressing from the OP's original question; where's the congestion occurring? OR, how do you know that there is congestion?

I think it's congestion because the cameras (analog) fall out of real time sync. There's one DVR plugged into the same switch as the computer that's running the surveillance software, the other two DVR's have to come through a single cable to reach the switch the surveillance computer is plugged into. I definitely don't think it's bandwidth. My theory is that the constant steam of packets (not sure if tcp or udp) from the 2 DVR's through one cable is causing it. They are a bit old. 1080p

Thanks for all the replies.