Restrict Access by IP Address, Subnet, or Domain

If you have a small number of clients who do not use newsgroups, you can create a group of restricted computers that cannot access the NNTP virtual server. Limiting access to server resources enhances security and can improve performance by reducing the load on the server. By default, all computers can access the NNTP virtual server until you identify a group of restricted IP addresses, subnets, or domains.

Warning   Identify a restricted computer by IP address only if you assign IP addresses statically. If a DHCP server assigns temporary IP addresses to computers, you cannot ensure that a computer will always have the same IP address.

To restrict access by IP address, subnet, or domain:

1. Start System Manager
   On the Start menu, point to Programs, point to Microsoft Exchange, and then click System Manager.
2. Navigate to NNTP.

   Servers

   1. Server
   2. Protocols
   3. NNTP
3. In the console tree, right-click a virtual server, and then click Properties.
4. On the Access tab, click Connection.
5. In the Connection window, select All except the list below if it is not already selected, and then click Add.
6. In the Computer window, select one of the following options:
   • IP address. Type the static address of a single computer; for example, 192.168.114.201.
   • 
     
     

     Tip  If you know only the name of the computer, click DNS Lookup. Type the name of the computer, and then click OK. If the IP address is resolved, it appears automatically in IP address.

   • Group of Computers. Type the subnet address and mask; for example, a subnet address of 172.17.131.0 and a subnet mask of 255.255.250.0.
   • Domain. Type the complete domain name; for example, nwtraders.microsoft.com.
7. To add the user, subnet, or domain to the list of restricted users, click OK.

Note  Restricting a computer's access to one virtual server does not necessarily restrict access to all NNTP virtual servers. You must restrict the computer's access to each virtual server if you do not want that computer to access any service. If you restrict a computer from accessing only one instance of an virtual server, depending on how you configure access to the other virtual servers, the computer may still have access to other NNTP virtual servers.