To access the modem you have two IP addresses:
afterwords you type in username: Administrator and the password that you've setup when you've configured the modem.
Here is a quick guide on how to work with CLI on Thomson Speedtouch modems: http://www.sdharris.com/speedtouch510/
Here is how to enable configuration for FW Level:Standard with CLI:
{Administrator}=>:firewall level modify name=Standard index=2 readonly=disabled
Here you can read more about IDS and SIF on Thomson GW devices: ConfigGuide_SIF (.pdf) via http://forums.whirlpool.net.au/archive/1223082