Huawei EC325(BSNL,Reliance,TataIndicom) in Linux(Ubuntu)

First check whether the command sudo /etc/wvdial in terminal.
If it doesn't exist,download and install wvdial and its related ones.

Now we can configure wvdial. We’ll need to edit the wvdial.conf file. So do this:
$ sudo gedit /etc/wvdial.conf

it so that the [Dialer Defaults] section looks like this:

[Modem0]
Modem = /dev/ttyUSB0
Baud = 115200
SetVolume = 0
Dial Command = ATDT
init1 = ATZ
init2 = AT+CRM = 1
New PPPD = yes
FlowControl = Hardware(CRTSCTS)

[Dialer bsnl]
Username = XXXX
Password = xxxx
Phone = #777
Stupid Mode = 1
Inherits = Modem0
After saving the file run the command
sudo wvdial bsnl.

If u had any problem...pls put comments...
Cheers!