Gamalsemlan, that device is an ADSL modem, router *and* firewall. It also has a switch.
Try open your web browser and set as the address:
http://192.168.1.1
That seems to be the address XAVi uses at least for its other routers. I am stull unable to find anything spesifically for your modem
If it all goes well, you should now be asked for login and password. The default XAVi login is
root, and the default password is also
root. However, if that does not work, try to login as
admin (password
admin).