3Com 3CR856-95 manual Setting up NAT, Configuring a Pptp connection

Configuring a PPTP connection

If your ISP has allocated you a dynamic address using PPTP you will have selected PPTP (used by some European providers) as your IP Allocation Mode.

Figure 37 PPTP Setup Screen

To setup the Gateway for use with a PPTP connection the following fields will need to be completed.

■IP Address — The internet address allocated by your ISP for this connection is automatically configured and is not editable.

■PPTP Server Address - This is typically the address of your modem.

■PPTP User Name - The user name you use to access your ISP.

■PPTP Password - The password you use to access your ISP.

■Primary DNS Address - The address of your ISP’s Domain Name Service server is automatically configured and is not editable.

■Secondary DNS Address - The address of your ISP’s secondary Domain Name Service server. The second server is optionally provided by an ISP in case of failure of the primary server.

■Maximum Idle Time - The amount of time without activity before the Gateway terminates the Internet connection.

■Initial IP Address and Initial Subnet Mask - IP settings must be used when establishing a PPTP connection. Alternatively, if the PPTP server is located in your DSL modem, click Suggest to select an IP address on the same subnet as the PPTP server.

Setting up NAT

The Gateway is able to perform Network Address Translation (NAT) in one of two modes as shown in Figure 38:

■One-to-many NAT — The Gateway shows only one address to the Internet.

■One-to-one NAT — Every address on the Internet pool is linked to an address in the LAN pool. The Gateway will respond to all the addresses in the Internet pool.

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