I recently took over managing my church's IT resources. Previously it was managed by nobody and so was subject to any random person or vendor's half-baked idea for building out the network. Right now we have a wired network and a wireless network on separate partitions; the wireless one is for public use and the wired is for our actual work network.
The biggest problem right now is that anybody with an ethernet cable can plug in to any port and get instant access to our internet connection and any unsecured resources on the network, including printers, non-password-protected shares, domain directory listings, etc. I've tried to look up some information on this but apparently I don't know the right terminology and so haven't found much of anything helpful.
What are my options for locking down our wired network so that users who don't log in to the domain can't access any of these things? (If it's of relevance, our server is running Windows Server 2k3 and does contain an Active Directory controller; our network hardware consists of a set of Cisco switches and a Cisco 881 router, which pumps both the wired and wireless network.)