Reference Manual for the Double 108 Mbps Wireless Firewall Router WGU624

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MTU Size:

The default MTU size is usually fine. The normal MTU (Maximum Transmit Unit)

value for most Ethernet networks is 1500 Bytes. For some ISPs, particularly some using PPPoE,

you may need to reduce the MTU. This should not be done unless you are sure it is necessary for

your ISP.

Any packets sent through the router that are larger than the configured MTU size will be

repackaged into smaller packets to meet the MTU requirement. To change the MTU size:

Under MTU Size, enter a new size between 64 and 1500. Then, click Apply to save the new

configuration.

Connect Automatically, as Required:

Normally, this option should be Enabled, so that an

Internet connection will be made automatically, whenever Internet-bound traffic is detected. In

locations where Internet access is billed by the minute, if this causes high connection costs, you

can disable this setting.

If disabled, you must connect manually, using the sub-screen accessed from the Router Status

menu, Connection Status screen.

Configuring LAN IP Setup Options

The LAN IP Setup feature is under the Advanced heading of the main menu. This feature allows

configuration of LAN IP services such as DHCP and RIP.

The router is shipped preconfigured to use private IP addresses on the LAN side, and to act as a

DHCP server. The router’s default LAN IP configuration is:

•

LAN IP addresses—192.168.1.1

•

Subnet mask—255.255.255.0

These addresses are part of the IETF-designated private address range for use in private networks,

and should be suitable in most applications. If your network has a requirement to use a different IP

addressing scheme, you can make those changes in this menu.

From the main menu of the browser interface, under Advanced, click LAN IP Setup to view the

menu shown below.

Reference Manual for the Double 108 Mbps Wireless Firewall Router WGU624

Advanced Configuration

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Figure 7-4:

LAN IP Setup Menu

The LAN IP parameters are:

IP Address:

This is the LAN IP address of the router.

IP Subnet Mask:

This is the LAN Subnet Mask of the router. Combined with the IP address, the

IP Subnet Mask allows a device to know which other addresses are local to it, and which must be

reached through a gateway or router.

RIP Direction:

RIP (Router Information Protocol) allows a router to exchange routing

information with other routers. The RIP Direction selection controls how the router sends and

receives RIP packets. Both is the default.

•

When set to Both or Out Only, the router will broadcast its routing table periodically.

•

When set to Both or In Only, it will incorporate the RIP information that it receives.

•

When set to None, it will not send any RIP packets and will ignore any RIP packets

received.

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RIP Version:

This controls the format and the broadcasting method of the RIP packets that the

router sends. (It recognizes both formats when receiving.) By default, this is set for RIP-1.

•

RIP-1 is universally supported. RIP-1 is probably adequate for most networks, unless you

have an unusual network setup.

•

RIP-2 carries more information. Both RIP-2B and RIP-2M send the routing data in RIP-2

format.

•

RIP-2B uses subnet broadcasting.

•

RIP-2M uses multicasting. Multicasting can reduce the load on non-router machines

because they do not listen to the RIP multicast address and will not receive the RIP

packets. However, if one router uses multicasting, then all routers on your network

must use multicasting.

Using the Router as a DHCP Server

By default, the router will function as a DHCP (Dynamic Host Configuration Protocol) server,

allowing it to assign IP, DNS server, and default gateway addresses to all computers connected to

the router's LAN. The assigned default gateway address is the LAN address of the router. IP

addresses will be assigned to the attached PCs from a pool of addresses specified in this menu.

Each pool address is tested before it is assigned to avoid duplicate addresses on the LAN.

For most applications, the default DHCP and TCP/IP settings of the router are satisfactory. See

“IP

Configuration by DHCP”

on

page B-10

for an explanation of DHCP and information about how to

assign IP addresses for your network.

If another device on your network is the DHCP server, or if you will manually configure the

network settings of all of your computers, clear the ‘Use router as DHCP server’ check box.

Otherwise, leave it selected.

Specify the pool of IP addresses to be assigned by setting the Starting IP Address and Ending IP

Address. These addresses should be part of the same IP address subnet as the router’s LAN IP

address. Using the default addressing scheme, you should define a range between 192.168.1.2 and

192.168.1.253, although you may wish to save part of the range for devices with fixed addresses.

Note:

If you change the LAN IP address of the router while connected through the

browser, you will be disconnected. You may need to restart your computer for the new

IP address setting to take effect.

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The router delivers the following parameters to any LAN device that requests DHCP:

•

An IP Address from the range you have defined

•

Subnet Mask

•

Gateway IP Address (the router’s LAN IP address)

•

Primary DNS Server (if you entered a Primary DNS address in the Basic Settings menu;

otherwise, the router’s LAN IP address)

•

Secondary DNS Server (if you entered a Secondary DNS address in the Basic Settings menu

Using Address Reservation

When you specify a reserved IP address for a PC on the LAN, that PC always receives the same IP

address each time it accesses the router’s DHCP server. Reserved IP addresses should be assigned

to servers that require permanent IP settings.

To reserve an IP address:

1.

Click the Add button.

2.

In the IP Address box, type the IP address to assign to the PC or server (choose an IP address

from the router’s LAN subnet, such as 192.168.1.X).

3.

Type the MAC Address of the PC or server.

Tip:

If the PC is already present on your network, you can copy its MAC address from the

Attached Devices menu and paste it here.

4.

Click Apply to enter the reserved address into the table.

Note:

The reserved address will not be assigned until the next time the PC contacts the router’s

DHCP server. Reboot the PC or access its IP configuration and force a DHCP release and renew.

To edit or delete a reserved address entry:

1.

Click the button next to the reserved address you want to edit or delete.

2.

Click Edit or Delete.

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Using a Dynamic DNS Service

If your network has a permanently assigned IP address, you can register a domain name and have

that name linked with your IP address by public Domain Name Servers (DNS). However, if your

Internet account uses a dynamically assigned IP address, you will not know in advance what your

IP address will be, and the address can change frequently. In this case, you can use a commercial

dynamic DNS service which will allow you to register your domain to their IP address, and will

forward traffic directed at your domain to whatever your current IP address happens to be.

The router contains a client that can connect to many popular dynamic DNS services. You can

select one of these services and obtain an account with them. Then, whenever your ISP-assigned

IP address changes, your router will automatically contact your dynamic DNS service provider,

log in to your account, and register your new IP address.

From the main menu of the browser interface, under Advanced, click Dynamic DNS.

Figure 7-5:

Dynamic DNS menu

Note:

If your ISP assigns a private WAN IP address (such as 192.168.x.x or 10.x.x.x),

the dynamic DNS service will not work because private addresses will not be routed on

the Internet.