Chapter 9: Technical Reference

Routing

You can configure the Megabit Modem 410F and 420F router to route Ethernet-encapsulated IP datagrams based on IP addresses. Use Routing Information Protocol (RIP) to automatically identify the route from the connection on the transmitting modem to the receiving modem. You can specify the direction and version of RIP that allows other routers to update their routing tables automatically (for example, information on how many hops between destinations) with the RIP Version and RIP Direction parameters (see page 50). The version of RIP you select for the connection must match the version on the receiving modem. Versions RIP 1 and

RIP 1 compatible use broadcast. Version RIP 2 uses multicast.

The router also learns addresses. In addition to the addresses it learns, you can add 32 static route entries using the Static Route Entry page (see page 51). Through the static IP routing feature, you can configure the modem as an IP router with statically programmed route entries. You can enable this function to provide broadcast filtering and to prevent eavesdropping by specifying multiple destination gateways. When static IP routing is enabled, you can access only specific remote IP subnets or hosts.

Since IP routers make forward or filter decisions based on the network-layer IP address instead of the MAC hardware address, MAC-level broadcast frames are prevented from reaching unwanted destinations in the network.

DHCP

The Megabit Modem 410F and 420F support Dynamic Host Configuration Protocol (DHCP). If you enable DHCP, the modem acts as a DHCP server and automatically assigns IP addresses to devices on the LAN. Ensure that the TCP/IP properties are set on the PC operating system (such as Microsoft Windows 95) to automatically obtain the IP address from the modem.

Megabit Modem 410F and 420F User Manual

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