Local Management: Overview, Setup, and Navigation26Subnet Mask (Modifiable)This field contains the subnet mask for the selected module. A subnet mask“masks out” the network bits of the IP address by setting the bits in the mask to 1when the network treats the corresponding bits in the IP address as part of thenetwork or subnetwork address, or to 0 if the corresponding bit identifies thehost. The default subnet mask uses the first two portions of the IP address toidentify the network id, leaving the rest of the IP address to identify specificnodes. To enter a new subnet mask, highlight the field and enter a new valueusing dotted decimal notation (4 decimal values between 1 and 255 separated byperiods) as follows:255.255.255.255(The Subnet Mask field defaults to the natural mask value, based on the IPaddress that was entered for the device.)Default Gateway (Modifiable)This field contains the IP address of the device to which all packets addressed toan unknown network or host are sent. If a Default Gateway is not configured, anypackets that are addressed to an unknown network or host will be dropped. Thisfield is not defined until a user enters an appropriate value using dotted decimalnotation (4 decimal values between 1 and 255 separated by periods).Default Interface (Toggle)This field contains the number that represents the interface that is connected tothe module’s Default Gateway. In some instances, dissimilar modules havedifferent corresponding interface numbers. For example, if a user is assigning adefault interface to a 9T122-24 module and enters a 3, then the default interface isthe Flexible Network Bus. However, if a user is assigning a default interface to a9F310-02 module and enters a 3, then the default interface is the Internal NetworkBus. The default is NONE, meaning no default interface selected.Base MAC AddressThis field displays the MAC Address of the selected module. This is the MACAddress of the SMB-10 interface.TFTP Gateway IP (Modifiable)This field displays the IP address of the router that connects to or is closest to themodule. Configure this address when a user is performing TFTP downloads in arouted environment (if proxy ARP is disabled on the router).The Default Interface field becomes active after a user enters an IP address in theDefault Gateway field.NOTE
