Help VLAN newbie! Can I control CTV traffic on one netgear switch?

[reggiep]

Hi,

We have just had a couple of CCTV cams installed on a new netgear switch (fs728tp) and now I'm wondering if it would be better if they were on a VLAN?

The CCTV installers who fitted the whole kit a while back told me that they wouldn't affect our network but I'm not sure that is true.

Leaving aside if they are right or wrong my system is as follows.

One switch with the CCTV server and the CCTV cameras and one connection back to our main switch cab.

I have never had any VLAN experiences before but could I somehow set the cams and the CCTV server up on one, leave the connection going back to the main switch cab off the vlan or is there more to it than that??

 

Thanks

[reggiep]

Sorry, also if I were to get a second netgear switch later, could I set up the same VLAN ID and add the ports on that new switch to the same ID. Or am I getting this totally wrong?

[FN-GM]

Not dealt with netgear but we put all our CCTV cameras on a separated VLAN. It made thing things easier to manage to start with. depending on what cams you have they can hog bandwidth so I would look at your uplinks. Ours are 720P, enough said!

[Boredguy]

Yes you can set the CCTV camera network ports to be on a different vLAN so the data is kept separate from your main network, but that will not resolve any data issues on the connection from that switch back to your main cabinet.

 

If you add additional switches in the future, you can setup the same vLan ID to expand your network.

 

In your example, You would need to setup a new vLan on your switch (say ID 20) and set the pVID for the ports connecting to the CCTV to 20.

You would also need to tag the uplink port back to your main switch for vLan 20

 

On your main switch, you would need to replicate the vLan 20 tag for the link to your CCTV switch, as well as configure the ports that route the camera footage back to your recording device.

If you do not view the DVR over the network then it's just a case of setting tags and pVIDs from point A to point B, but if your DVR is accessed via the network then your better off leaving it as is as the routing will get a bit more of a headache.

[roadhouse1387]

Hi Reggiep

 

All good advice from the previous posters, if I could add to that by adding some further points.

 

if you add your new vlan to a trunk (cisco speak.. 802.1q link, not an HP channel) port carrying all other vlans to your core switch, you will see no improvement on performance as in the end a vlan is nothing more than an Ethernet frame with a vlan tag in it and as such it will consume bandwidth along with all other vlans on the link. You may get some benefit from using a seperate link as a last resort but be mindful of spanning tree.

 

If you are experiencing performance issues over your netgear with your cameras on the go , its more likely related to the throughput performance of the netgear rather than bandwidth congestion. Netgear switches in common with other low end tin have small egress buffers and processors and in general will have difficulty maintaining the packet forwarding rates required as your network scales and you add more cameras, of course, it all depends on the codec being used. 720p can be anywhere from 5 to 10 mbps depending on the codec. QoS may help here but you cant create more buffer space out of thin air if the switch isnt big enough. Consider a switch from a tier one vendor such as Cisco if you need to upgrade.

 

IPCCTV uses Multicast to forward traffic, whilst this will work ok if all the cameras/recorders/controllers etc are on a single vlan/broadcast domain, you will need a multicast capable layer 3 switch or router to get that traffic across from one vlan to another. Even then you may find that it doesn't work due to TTL counts which are hardcoded into the multicast IP header by the camera manufacturers. Some vendors set this to one which effectively means routers throw it in the bin as soon as they see it and dont forward it. This would mean that you would need to span a vlan across all your switches where you have cameras. Of course we know that this is common practice (flat networks), but its actually a very bad practice as it increases the size of a failure domain to every switch carrying a common vlan. Flat networks are suseptable to instabilities caused by spanning tree and bad root bridge placement as well as broadcast storms and MAC over subscription. Routed designs are much better.

 

Cheers

Shaun

Edited May 15, 2014 by roadhouse1387

[Asgard]

Reggie we use VLANS on Netgear's and are just down the road from you.

 

http://techdataukinfo.co.uk/microsites/public-sector/docs/netgear/netgear_case_study.pdf