Linksys BEFSRU31, BEFSR41 Dynamic IP Addresses, DHCP Dynamic Host Configuration Protocol Servers

Instant Broadband™ Series

Dynamic IP Addresses

A dynamic IP address is automatically assigned to a device on the network, such as PCs and print servers. These IP addresses are called “dynamic” because they are only temporarily assigned to the PC or device. After a certain time period, they expire and may change.

If a PC logs on to the network (or the Internet) and its dynamic IP address has expired, the DHCP server will assign it a new dynamic IP address.

DHCP (Dynamic Host Configuration Protocol) Servers

PCs and other network devices using dynamic IP addressing are assigned a new IP address by a DHCP server. DHCP frees you from having to assign IP addresses manually every time a new user is added to your network.

DHCP servers can either be a designated PC on the network or another network device, such as the Cable/DSL Router.

By factory default, a DHCP server (LAN side) is enabled on your Router. If you already have a DHCP server running on your network, you must disable one of the two DHCP servers. If you run more than one DHCP server on your network, you will experience network errors, such as conflicting IP addresses. To disable DHCP on your Router, see the section on DHCP in The Cable/DSL Router’s Web-based Utility.

Even if you assign a static IP address to a PC, other PCs can still use DHCP’s dynamic IP addressing, as long as the stat- ic IP is not within DHCP range of the LAN IP Address.

If the dynamic IP addressing fails to provide a dynamic IP address for any reason, please refer to the Troubleshooting Section.

EtherFast® Cable/DSL Routers

Connecting Your Hardware Together and Booting Up

1.Before you begin, make sure that all of your hardware is powered off, including your Router, PCs, hubs, switches, and the cable or DSL modem.

2.A. If you have the 4-Port Cable/DSL Router, connect one end of a network cable to one of the LAN ports (labeled 1, 2, 3, or 4) on the back of the Router, and the other end into a standard port on a network device, e.g., a PC, print server, hub, or switch. See the Twisted-Pair Cabling section for details on network cabling.

A standard port is any port other than the WAN port

and the Uplink port. It’s a straight-through port.

Repeat the above step to connect more PCs or network devices to the Router.

2.B. If you are connecting the 1-Port Router to just one PC, plug one end of a network cable into the Router’s LAN port and the other end into the PC’s network adapter port. Set the Crossover Switch to straight-through mode ( ). If the straight-through mode does not light up a Link LED, see the chart in the Getting to Know the 1-Port EtherFast Cable/DSL Router section.

If you are connecting the 1-Port Router to a hub or switch, plug one end of a network cable into the Router’s LAN port, and the other end into to a standard port on your network’s hub or switch. Set the LAN port’s Crossover Switch to its straight-through ( ) mode. Please refer to the chart in the Getting to Know the 1-Port EtherFast Cable/DSL Router section.

If your hub or switch has no more standard ports available, connect the Router using its LAN port to the Uplink port on the hub or switch. Set the Crossover Switch to straight-through mode ( ) for this set-up.

2.C. If you have the 3-Port Cable/DSL Router, connect one end of a net- work cable from the one of the Router’s LAN ports (labeled 1, 2, or 3) to a port on a PC, hub, switch, or other network device.

The 3-Port Router features one USB plug-and-play port that connects instantly to any USB-ready PC or hub. This allows you to connect to and access your Router without even installing any network cards.

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