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New Member

Looking at VLANS

We have 3 office branches.

The central office has about 200 nodes, and the 2 remote branches have about 20 each. The remotes are connected via Frame Relay, and we are currently bridging, but will be migrating to EIGRP routing.

I am unsure as to when a migration of our 200 node flat network in the central office to VLANS would be justifiable.

Any thoughts?


Re: Looking at VLANS

Depends on a number of factors:

- protocol used (IPX is more "chatty" and more broadcasts than IP)

- security concerns (place access-lists on vlans, or on private vlans)

- amount of traffic generated

- need for increased performance

- need for improved managability

I believe IPX networks shouldn't have more than 300 nodes in one subnet, while IP can have 500 nodes and I think Appletalk is 200 nodes. Again, this is a general rule and subject to your traffic pattern and amount of broadcasts.

But for your network size I don't think you need EIGRP, with or without vlans, static routing would work.

I would use vlans, based on department or user groups (acls if needed), and static routes.

Hope it helps.


New Member

Re: Looking at VLANS

We're running IP only.

We had a consultant in recently that said we were too small to use vlans, and I was curious as to whether he had a valid point or not.

The problem is that we do not have any real network monitoring hardware or software (sniffers, analyzers, etc), so I honestly don't know if we are actually experiencing broadcast storms, but I do know whe have a lot of netbios traffic.

Re: Looking at VLANS

You could argue either way, but I would do it for no other reason than dividing users based on depart/group and adding acls.

As for network monitoring, look into MRTG: . Free software you can install and configure in one hour that lets you know which ports are doing what. If the network device has a MIB, MRTG can grab it. Great software that should help, and it's free.

Hope it helps.