Network subnets in Lync Server 2010 are the glue that binds a client connection to a specific network site, and region. When a Lync client performs an action that requires network awareness, the client IP address is examined and then used to determine the appropriate action based on the associated policies with the endpoint subnet.
Use the following steps to create a new network site:
1. Open the Lync Server 2010 Control Panel.
2. Click Network Configuration.
3. Click Subnet.
4. Click the New button.
5. Enter a Subnet ID that is the actual network IP address.
6. Enter a Mask for the subnet. This value is the number of bits used for the subnet mask. For example, if the subnet uses a 255.255.255.0 mask, enter 24 for this value. ...