If you are using Linux based laptop at an office or a home, then you may need to configure your Linux system for different network environments.

In good old days, I had couple of shell scripts to change network settings. However, you may find small nifty utility called netenv very useful. When booting your laptop it provides you with a simple interface from which you can choose the current network environment.

You can select the network environment you want from list. netenv works on

1. Debian Linux
2. Red Hat Linux
3. Suse Linux

You can download netenv here or if you are using Debian Linux use apt-get command to install it:

# apt-get install netenv

To configure or to select new network interface just type command:

# netenv

On Debian systems, netenv can work with both PCMCIA and on-board network cards. You can also use netenv to configure your windowmanager or your printing environment.
Please note that if you are using Red Hat Enterprise Linux then you can configure network profile with inbuilt Red Hat network configuration tool:

# redhat-config-network

Above tool can be used to create multiple configuration sets for different networks. A configuration set can include logical devices as well as hosts and DNS settings. After configuring the profiles, you can use the Network Administration Tool to switch back and forth between them.