Adding a Second Subnet to an Existing Network

I have a small network that is set up with an IP scheme of 10.0.0.x

This network serves an office area of about 100 PCs. Additionally, it will see another 40 to 50 wireless devices connected (phones, tablets, etc.) on any given day.  The 254 addresses are more than sufficient for my current needs.

What I am wanting/needing to do is create a second subnet for IP-enabled equipment and PCs on a manufacturing floor.  There will be probably 120 to 130 devices in this environment.

I need these two segments to be able to talk when needed.

Please offer me suggestions on how to best segment my network.

What equipment do you suggest?
Is my logic of subnetting reasonable?
What pitfalls may I encounter.

Additional info:

I am not a networking guru so a straight-forward solution is preferred.
Right now, my Windows Server (DC) hands out the IP addresses for my network.

If I've left out anything important, you'll just have to excuse my ignorance and follow up with a question of your own to ferret out my "real" needs.
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

You need a device that can do IP routing, also called layer 3 (L3) switching these days.

Since you have 100 or so devices you must have some type switches in your network. What type do you have (brand and model)?
DesideriusErasmusAuthor Commented:
We're using Dell PowerConnect 2848 switches.  

I'm still learning how this network is set up...I was thrust into managing the network since a downsizing.  My technical background is in applications development, but I left that behind nearly seven years ago when I finished an accounting degree.

I was thinking that I'd need a router or it's possible that I don't need additional hardware then?
Fred MarshallPrincipalCommented:
This diagram may give you some ideas.  It was developed with the idea of isolating the subnets.  In order to allow communication between the subnets all you need are some added routes.

For example, in the "parallel routers" type of configuration, on the second page, you would add one route each to the parallel routers:

On Router 2: to where xxx is the WAN IP address of Router1

On Router 1: TO 192.168.1.yyy where yyy is the WAN IP address of Router 2

These can be rather simple commodity routers.  They don't have to do much.

It may be possible to add these routes to what is shown as the Modem/Router (which can just be your internet gateway router and not necessarily a modem at all).  That would add 1 hop but by itself isn't a big deal.  The real issue is what your boxes there will support.  Most likely almost any router will do.

Similar comments apply if you do this according to the first page with the routers cascaded.  You could cascade down to the manufacturing subnet at the bottom of the page.
Generally the lower subnet devices can reach the upper subnet devices without added routes.  But to get the upper subnet devices to reach the lower subnet, you will normally need a route added at the modem/router device.  For this, Router 2 isn't needed at all.  Just add Router 1.
Powerful Yet Easy-to-Use Network Monitoring

Identify excessive bandwidth utilization or unexpected application traffic with SolarWinds Bandwidth Analyzer Pack.

James HIT DirectorCommented:
Since this a a managed switch, why not just create a VLAN for that  floor.
This way there is no need for a router and adding too much complexity to the environment.

Each VLAN you create can be set with its own subnet.

EX. VLAN 101 - Subnet:

VLAN 201 - Subnet:


Just tag thoss ports or the the switches those devices are connecting to and they will report on that subnet and give you the flexibility without the need for additional equipment (as long as all switches in your network are managed).

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
DesideriusErasmusAuthor Commented:
That sounds pretty good.  I've never done anything with VLANs.  Will it be pretty easy to set up?
Fred MarshallPrincipalCommented:
So far everything I've read suggests that you need a router to interconnect the VLANs.  But, maybe this function is built into that switch.  If so, I wasn't able to quickly find it in the manual.
The switch does support VLAN, so you can create a new VLAN and give it its own IP subnet.  However the switch does not support L3 routing.  

So if you need to have hosts that are in separate VLAN/IP Subnets then you need to get router.
DesideriusErasmusAuthor Commented:
Can someone recommend a router that is fairly straight forward to configure?

Do I need one or two routers?
Fred MarshallPrincipalCommented:
Well, I've used the Cisco Small Business RV042 in a number of roles and that seems to meet a reasonable set of needs.  They aren't expensive at all.  They are easy to configure with a graphical interface.

You could set one up in "Router" mode to avoid any NAT and could interface between the two VLAN subnets.  

One is enough unless there are other considerations.  That is, I don't understand how you have the internet access set up with the two VLANs.......
DesideriusErasmusAuthor Commented:
Thanks for all the input.  I'm going to set up VLANs and try to insert the RV042 router into my network.
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Windows Networking

From novice to tech pro — start learning today.