Subnetting & More

[timbrigham]

Hello everyone.
I work for a small company with a rather? unsophisticated network topology.
The setup was like so:
Three 100 MB switches daisy chained together, which then are connected to a 1 GB switch.
This gigabit switch was then connected to another gigabit switch.
The second gigabit switch has all the servers and the firewall attached.

So far, I have rearranged the network to where the first gigabit switch has all of the 100 MB switches attached straight to it, star configuration.

I?m looking at doing the following:
Getting a layer 3 switch / router (probably a switch for the size of our network, not sure yet) and breaking the network into separate subnets, based on which switch a user is on. This would allow us to fairly easily separate processing, accounting, etc.
Should I also separate all the printers off into a single subnet? There are probably 24 printers in the building, and no matter what I do it seems there will be people in separate subnets trying to print to the same printer. Would a separate subnet be a good thing here, or should I leave them where they are?

Also, the physical configuration of the building dictates that the T1 line runs into the room which houses the 100MB switches and the first GB switch. At current the firewall is in the second room containing the firewall, servers, and the second GB switch. I would like to move the firewall back into the networking room, but this would mean that the servers would have an extra jump to the internet, where as the users would have one less. If/How would this impact the performance of the servers for web access (EG mail server?)

Thanks..
Tim

 

[lansalot]

They wouldn't notice it I'd doubt. Is a T1 > 100mbit?

 

[spidey07]

what is the total number of hosts? (printers, servers, pcs, etc)

If its under 200 you really don't need a layer3 switch.

 

[Loki726]

Originally posted by: lansalot
They wouldn't notice it I'd doubt. Is a T1 > 100mbit?

T1 = 1.5MBs up and down

 

[ronzilla]

If you're going to break the network into subnets, you're going to need either a Layer 3 switch or a Layer 2 switch with a router. You have to have something that works on Layer 3 (switch or router) to route between subnets. Personally, I'd go with a Layer 3 switch. With a router, you'd be limited to the number of VLANs you could use (depending on the number of ethernet interfaces in the router). In the switch, you wouldn't have that limitation.

I have a Cisco 3550 (layer 3 switch) and a 3508 (layer 2 fiber switch) together in a VTP domain for some things similar to what you've mentioned. You probably don't need the 3508 (I run fiber through a building and underground to a building next door) and could use GBICs in the 3550 to uplink to your gig switches. Then you'd have plenty of 10/100 ports to uplink to your 100mb switches (in the star configuration, like you mentioned).

I'd put the printers on the same VLAN as the print server. If you don't mind them being on the same subnet as your servers, that would work. If not, you could make them be a part of the same VLAN as some users. I can't think of an advantage of going either way, really.

The extra "jump" to the internet that you mentioned is not an issue. Switches don't count as a hop when it comes to routing (unless, of course, the switch is routing). You won't notice the difference in speed to the internet either way you go.

I'm doing some pretty cool stuff with 802.1q that gives me awesome flexibility with my VLANs. I can put any of my internal VLANs on any of my switches in any of our buildings. It really makes me look smart when somebody wants a weird configuration with ports in different VLANs. If your gig and 100mb switches support it, you should consider it. The 802.1q stuff was fun to learn and is really easy to admin.

 

[SaigonK]

Seems like a lot of overkill for such a small office, i doubt they are seeing any performance issues with your current config, why spend the $$ for something that really doesnt do anything better?