VLANs and interfacing PCs with systems

vegastech

I am looking forward to introducing VLANs into our system designs. From what I understand, VLANs allow traffic to remain inside their individual LANs when possible. Let's say I have 2 networks, 192.168.1.0 and 192.168.2.0. If my processor is on the 2.0 network and my PC is on the 1.0 network, do I need to create a static route on both machines in order to contact the other, or is there something else I need to do? I am thinking specifically about the iPod sync function on an iPort, as well as using PC control in the project.

vining

That would be individual networks not VLANs. You can have seperate nertworks and create static routes between the routers but VLANs can give you more flexability down the road. Of course w/ dual LAN if one network fails you still have the other while if using VLANs the network fails you'll likely loose everything. That said, how often do networks fail? Rarely.

Of course w/ VLANs all your traffic is on one network so you should get a managed switch w/ an adequate back bone. The Cisco 2960 cisco mentioned on the "Just Add Power" post is a good choice. If you use multiple switches you'll need all your switches to be capable of 802.1Q trunking on ports that connect the switches together (I think that's the right number). That will allows you to pass VLANs from switch to switch unless just one switch can handle the VLANs.

vegastech

So i guess I am missing the point of VLANs - if it is all on one PHYSICAL network, what is the purpose? Simply not broadcasting to the other VLANs?

vining

vegastech wrote:

if it is all on one PHYSICAL network, what is the purpose? Simply not broadcasting to the other VLANs?

Basically yeah, but if you think about it the world is just 1 physical network too, seperated by routers and switches that determine where things go and who can receive stuff but we're basically all connected by wires in one big network.

A VLAN is simply a virtual LAN and ports assigned to VLANs append a tag to the packet headers and the switch "manages" the distribution to the other appropriate VLAN ports. These managed switches can have much higher capacity than the typical 10/100 switch. Some have 16 gigs or more back bones w/ 1 gig+ trunking ports (switch to switch w/ VLAN support). So it can easily give you the functionallity of seperate network isolation w/o any adverse affects of a congested network. The world model seams to work fine. Plus w/ VLANs you can assign a different QOS setting to the different ports, you can create spanning trees for redundant network loops and all kinds of other crap.

Multiple networks can be more of a pain to manage or maintain and subnetting can really hurt your brain.

vegastech

Old thread, I know. I was wondering - with a home system where I want to keep the client's computer traffic away from the AV equipment, a VLAN would be good for this, yes? But what about when it comes to sync'ing the client's ipod with their PC, while the ipod is docked in the AV equipment's dock? Would a VLAN prevent this, or is there something in place to accomodate for this situation? Our purpose was to offer a better-designed QOS system for future integration of IP phones, etc.

jweather

Normal unicast (point-to-point) traffic is already isolated from the A/V system -- that's the purpose of using a switch rather than a hub. Broadcast traffic is the only thing you would eliminate by putting the A/V system on a separate VLAN. I usually hear about this solution when there is something like a Kaleidescape system on the network that makes heavy use of broadcast traffic. A typical PC does not produce significant amounts of broadcast traffic.

Jeff Lockyear

Pakedge is making an all-in-one solution to this stuff, which should solve a lot of the set up headaches (so I've heard). We have our first kit coming in soon. I'm happy with their stuff so far, and I don't expect this to be any different.

http://www.pakedge.com/products_routers.php