Nowadays DSL connections have become very popular. But the user is usually not aware how the DSL connection is set up for Internet connectivity.

Hence here is a short introduction to a highly technical issue.

There are actually two ways to configure DSL broadband.

1. Using computer's PPPoE dialer: PPPoE stands for PPP over Ethernet. Here the modem is connected to the computer through Ethernet card or Network Interface Card(NIC). But the modem/router is put in bridge mode which is actually a default mode for most of the DSL modems/routers. The user configures a PPPoE dialer or xDSL dialer on the computer to connect to Internet. In this case the since the modem is in the bridge mode the the computer gets the wan IP or Internet IP address directly from the Internet Service Provider.

The advantage of this scheme is the programs which acts like server are directly accessible to other computers on the Internet and there is no need for port forwarding. The drawback of this scheme is that a hacker may get direct access to your computer through its IP address.

2. Using DSL Modem's/Router's PPPoE dialer: Here again the DSL modem/router is usually connected to the computer through computer's Ethernet card or NIC. But sometimes the DSL modem/router may may be connected to the computer through an USB Port.

In this connection what we have is a single computer LAN (Local Area Network).Here the use is made of modem's DHCP program. The modem's DHCP allocates a LAN IP address to computer which is typically 192.168.1.97 or 198.168.1.2.

The WAN IP address from the ISP is allotted to the DSL modem/router.

To use this method we need to change the default mode of DSL modem/router to PPPoE. This is usually done by opening the modem interface through a web browser like Internet explorer or Firefox, by typing a modem's/router's interface IP address which typically is 192.168.1.254 or 192.168.1.1, in the browser's address bar.

After opening the modem interface DSL modem/router may be put into PPPoE mode. You also need to enter your username and password given to you by your Internet Service Provider.

The advantage of this scheme is that the computer is behind the modem, hence it is quite difficult for a hacker to get access to the computer from Internet. But if you are using some programs which has server processes, you need to do port forwarding to allow computers on the Internet to connect to these servers.