N900 USB router

When the only internet link is the N900, how to connect a laptop to it and use it to connect to the net? This is the opposite use case of N900 USB networking.

On the N900

  1. Enable extras-devel
  2. Install iptables at a terminal with root access:
    apt-get install iptables
  3. Install kernel-power-settings (see the detailed installation instructions):
    apt-get install kernel-power-settings
  4. Setup iptables to allow forwarding:
    echo 1 > /proc/sys/net/ipv4/ip_forward
    iptables -t nat -A POSTROUTING -o wlan0 -j MASQUERADE
    iptables -t nat -A POSTROUTING -o gprs0 -j MASQUERADE
    
  5. Check the IP address for USB networking:
    cat /etc/network/interfaces
    iface usb0 inet static
    address 192.168.3.15
    netmask 255.255.255.0
    
  6. Bring the interface UP:
    ifup usb0
    
  7. Start dnsmasq on the usb0 interface to provide DHCP & DNS
    dnsmasq -I lo -z -a 192.168.3.15 -F 192.168.3.64,192.168.3.127
    

On the laptop

Use the IP address for USB networking from the N900 and configure the USB network device to use it as the default gateway:

sudo ifconfig usb1 192.168.3.14
sudo route add default gw 192.168.3.15

For Non-Power Users On Windows

The Nokia PC Suite also provides this functionality for Windows users. Once it is set up, click on the green globe icon to get started - or you can just run "OneTouchAccess" from the PC Suite program files directory (C:\Program Files\Nokia\Nokia PC Suite 7\ by default on Windows XP)