Our company is a small one and steadily growing towards mid size. We currently have about 200 or so users. Naturally we have run out of IP addresses and now we must redesign the entire IP schema. Initially our plan was to just implement a class B subnet for the whole network with certain ranges belonging to certain kinds of devices/machines/servers. Are there any cons to this? If so, could you link me to documentation that explains this? I read online about isolating broadcast domains, but that would require a huge cost for new routers and such. I feel that for our size it would not justify the cost of isolating broadcast domains right now. But if there are some huge cons to having the class b network now, then that would be helpful to know. Can someone offer some insight?

You are not going to see the "con" just by creating a class b network. What you will see is that the network will begin to "slow" down as you add more and more computers to the network. while you may already have a switched infrastructure, this ONE class B network is still going to be in the same broadcast domain. That means (as you may already know or have read) that broadcast packets will be delivered to all hosts in the subnet. So, If you grow to double the size, after a few years and compensate with GB switches, you may not notice that much of a difference. Just be aware that this is a con that you cannot work-around without creating VLANs.Visit: anITKB.com, an IT Knowledge Base.

You really need to segment your users by department or location before you get any larger. Throwing everyone into one giant VLAN is bad for performance, bad for security, and will end up costing you a lot more than a fancy multilayer switch (router) when you have to pay an outside consultant to come in and redesign everything.Matt W. CCNP, CCDA, CCNA-S, RHCT, MCSE, MCSA, MCP+I, A+

Hi, Thanks for posting here. Yes I agree , you should split you network to few IP segments ,whatever by using router , VLAN or event host with multi NICs, this will not only improve address space but also keep your network security. See the deployment scenario below: Small Office Network http://technet.microsoft.com/en-us/library/cc776089(WS.10).aspx Thanks. Tiger LiPlease remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.