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Can I saturate the physical lan? Should I avoid vlan

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Roveer

Occasional Visitor
I'm in the process of re-designing the network in our office. It's a somewhat unique setup in that is resides in a residence. We've had problems where I've been told "the network is acting up" Symptoms includes inability to stream music/video (tidal/napster/netflix), wifi stops working and number of other "it doesn't work" complaints.

The entire house 10k sq ft is cabled to a single location. I had put in a 24 port gig swtich (vlan capable) and a 24 port 100 mb switch that I had from another project. 10+ years ago there wasn't much going on, didn't even have wifi initially, no streaming just a handful of devices. I recently did an inventory and there are now over 40 devices, wired & wireless on the network doing all number of things. Several video streaming devices and lots of wifi devices, copiers, sonos, sensors etc.

Over the years my internet speed has gone up from 20/20 back then to FIOS gig now. I did find a major problem recently where one of my office file transfers was pegging the processor of my Checkpoint router/gateway/vpn appliance during a large file transfer across the device. I think this was probably the biggest issue I had, but I started looking a little deeper and realize now I have many more problems/inefficiencies.

My main network is 172.16.1.0 which feeds the entire network. I do have one vlan that serves a singular SSID on my WAP's for "guest mode".

Our office only has a couple of computers and a server, but I do large file transfers at night and move backups from the server to a workstation for DR purposes.

Initially I thought I should just vlan the "house" devices from the office devices to separate the traffic, but then I started to think what if I'm saturating the wire/switch/172 network with my large transfers, vlan would suffer just the same correct?

Just recently I've installed a pfsense router on an i7 computer with lots of Intel Ethernet ports so I started to think maybe I should separate house from office onto separate switches on their own networks and let the router route when I have to go between them. This would keep my large transfers on the office switch/network and keep the house devices (streamers, sonos, wifi, and other low use devices) on their own switch/network. This would give me physical network segmentation but the pfsense router will allow connectivity. That way when I'm hauling huge backups across my office network the traffic will stay on that switch/network and not even go up to the router and at the same time when the house wants to stream netflix and tidal hi definition music it's all separate. But if a laptop connected to wifi wants to get to the office server for email or files, the router can get them there. No need for vlans. One additional thing is I have a persistent ipsec vpn connecting my office network to my home across town. With the new pfSense router even when I hammer the vpn I only drive router cpu utilization to 14% so I'm not worried about effecting what would be the house network internet access (unless I saturate the FIOS connection).

I've never really considered that I might be saturating the physical network but I am measuring transfers between workstation and server at 900+ mb/s I guess that would only effect the specific switch ports (and devices on these ports) on my gig Ethernet switch, but is it possible to overwhelm the entire switch to the point where other ports would be effected? Layer 1/2? I have no way to see utilization on the switch itself. Presently this traffic doesn't even go to the router, but when i transfer across the VPN, it does impact the router, but only about 14% cpu utilization.

The days of plug it in, the light goes on and your good to go, are gone. These devices consume way too much bandwidth to just plunk down with all the other devices and not expect to see an impact. I used to think "but I do these transfers late at night/weekends, nobody will know" Our networks, even home networks, are 24/7/365. Having work and home on the same network actually makes things worse.

Does this make sense or should I be looking for a different solution?

Thanks for taking the time to read the entire saga, but I wanted to provide as much information as possible.

Roveer
 
no reasons to avoid vlans. VLANs dont put additional load unless your router has a 200Mhz MIPS 24kc CPU with 8MB of ram in today's internet speeds.

Saturating a physical network is very easy with ethernet. To overwhelm a switch it has to do with packet amounts, not bandwidth use.
 
Traffic on a switch is port to port. Today's gigabit switches handle wire-speed between all ports.

VLANs are handled in the switch and don't hit a router's processor. They are primarily useful to limit broadcast traffic (ARPs) and for security.

I would upgrade the 10/100 switch to gigabit and look at traffic between switches for bottlenecks. Also watch mix of 10/100 and gigabit devices on same switch to avoid flow control problems.
 
no reasons to avoid vlans. VLANs dont put additional load unless your router has a 200Mhz MIPS 24kc CPU with 8MB of ram in today's internet speeds.

Saturating a physical network is very easy with ethernet. To overwhelm a switch it has to do with packet amounts, not bandwidth use.

So I'm concerned about when I haul 200GB of data across the network at the same time there is a netflix stream going and some music being streamed. Of course I could just do some easy physical switch isolation and those different traffic's would never see each other, but do big transfers and streaming start to bulk up broadcast traffic (I'm not sure they do) and could cause problems that way?
 
So I'm concerned about when I haul 200GB of data across the network at the same time there is a netflix stream going and some music being streamed. Of course I could just do some easy physical switch isolation and those different traffic's would never see each other, but do big transfers and streaming start to bulk up broadcast traffic (I'm not sure they do) and could cause problems that way?
If you are streaming than no, you could just overwhelm the client's own physical connection. 4k netflix only requires 20Mb/s

The cheapest and best way is to use a managed switch and a multi port nic and do static bonding (not applicable to consumer windows OS)
 
Broadcast traffic is primarily driven by DHCP leases and renews and ARPs when a device connects to another for the first time. If your network is functioning normally, broadcast traffic should not take a large % of bandwidth.

Once the machines that need to communicate know each other's MAC address, they don't need to discover it again. Media streams and file transfers do not generate broadcast traffic.

If your high bandwidth connections are between different endpoints and are not crossing between switches, they should not affect each other.
 
Broadcast traffic is primarily driven by DHCP leases and renews and ARPs when a device connects to another for the first time. If your network is functioning normally, broadcast traffic should not take a large % of bandwidth.

Once the machines that need to communicate know each other's MAC address, they don't need to discover it again. Media streams and file transfers do not generate broadcast traffic.

If your high bandwidth connections are between different endpoints and are not crossing between switches, they should not affect each other.

That's what I was thinking. I'm overthinking this a bit and having found traffic that was maxing out my router's cpu was probably my biggest problem, which is now solved. I'm still on the fence as to whether or not to create separate networks for the office side and house side, probably not needed but still considering it.

It does give me some control in the firewall with the ability to set up rules to block/allow. More security. If I were to do same with vlan then configuration would be a bit more difficult for new devices and they would have to be vlan complatible. If I separate the networks then I don't have to worry (from a security standpoint) so much every time the house installs a new device (that I don't know about) which seems to be the norm. Will automatically be blocked from the work network unless they come to me and ask permission, then I can modify the rule.

Roveer
 
Traffic on a switch is port to port. Today's gigabit switches handle wire-speed between all ports.

Exactly - even commodity unmanaged customer switches are non-blocking...

VLAN's can help for breaking out broadcast domains, and have useful purposes for segmenting out subnets - most SOHO networks are fine on a flat topology.
 
If your high bandwidth connections are between different endpoints and are not crossing between switches, they should not affect each other.

This is the exact reason you want one large switch over multiple little switches.

Windows machines get pretty chatty talking to each other also besides DHCP. You can reduce the DHCP traffic by increasing the lease time to reduce the chattiness.
 

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