How to block port scans on Zyxel C1100z router? Every time I configure the IPv4 Firewall it reverts back to default settings.

Hello it depends on your router.
Read more here:

http://www.zyxel.com/support/knowledge_base/kb_detail_1850.shtml

http://www.default-password.info/zyxel/

Here is a video that shows how:

http://www.youtube.com/watch?v=19WI2dl-QU4

You might have to reset router to access the page.
Press the reset button at the back of your router for 30 sec.
and release.Wait for it to boot up again.
Now the router is set to factory settings.
Connect your lan cable to the router to one of the ports 1 to 4
and to your computer
To configure your router's wireless network open Internet Explorer and navigate to the router's configuration page by typing 192.168.1.1 into the address bar. When the page loads you will be prompted for your Router configuration password. By default this is 1234.
(You have to find the username and password first)

Try to download a manual for the router:

http://www.zyxel.com/support/download_library.shtml

Please select your model and number.

Do not use a easy password so others can use your internet connection.

Good luck

If you have servers on your LAN, configure an SUA server set to have them visible to the outside. From the NAT - Mode screen click Edit Details and fill in the fields as show
do this to setup a DMZ

Sometimes not just the dmz or port configurations cause your nat settings to be other than open, you may not have good internet connection, the better it is the more you will open. Most routers are open by default, and those others need to be forwarded(like you wrote) with the upnp open and specific ports for xbox/ps3 servers opened. You seem to know a little already, maybe time to get a new router?,I recently upgraded myself due to problems with configuration.

Hi there,

There was a small reset switch on your router, press the reset button for 5 second to reset the setting into default factory settings. Like in your case it is possible that the router need to reset for the first time.

Kindly let me know for further more assistance.

Thank you for using fixya.

micro-

you have to TURN ON both FIREWALL AND NAT, and then configure the nat forwarding + firewall rule and then it will work
it's a known bug @ zy boxes

The default address to get to the web interface is 192.168.1.1

The default password is 1234 (No username required)

If that doesn't work, you can restore it to the factory default by pressing the reset button on the back and holding it in for 10 seconds. Be aware that doing this will erase all existing configuration information.

Here's a link to the quick start guide:
ftp://ftp.zyxel.com/P-320W/quick_start_guide/P-320W_1.pdf

Here's a link to the Users Guide:
ftp://ftp.zyxel.com/P-320W/user_guide/P-320W_1.pdf

Hi Friend,
Before Connecting your internet we must check in ur system.

1.Go to Start---->Run------>type cmd----->in the black screen type ping 127.0.0.1
2.check wither its getting reply or request
3.If u are getting reply then ur system is perfect i.e., your NIC Card is installed properly.
4.check wither any proxy is enabled in the LAN settings.
go to browser--->tools---->internet options(Options)----->Connection--->Lan Setting--->there should noy be any tick mark in the boxes

Now we can check the connectivity,
1.Connect the PC from the Router Lan Port and the modem connectivity to the Wan Port of the Router.
2.Assign the Ip address as obtain ip address automatically

Right click networkplaces--->properties--->Lan Connection Properties---->double click the internet protocol(Tcp/IP).In the next box u must select the Obtain Ip address automatically

3.Now u switch on the modem after 30 sec switch on the Router.
4. Launch your web browser.
5 Type "192.168.1.1" as the URL.
6For administrator access enter the default admin password 1234 to configure the wizards
and the advanced features.
7 Click Login to proceed to a screen asking you to change your password or click Cancel
to revert to the default password.
8 If you entered the admin password, it is highly recommended you change the default
admin password! Enter a new password between 1 and 30 characters, retype it to
9.Then u can configure the ip address


Regards,
Ayyasam

ftp://ftp.zyxel.com/

this the web site download the user manual from this site what ur configuration go thought it i think you get it and maybe the problem in the pppoa line its working or not just check it

To log in to the router in order for you to do a port forwarding you can follow the steps from this link, but if the default username and password didn't work reset the router so it will be back to its default settings http://portforward.com/english/routers/port_forwarding/ZyXEL/P-660HW-T1v2/Age_of_Empires_III.htm

well to start, your connection would possibly be ADSL and your zyxel is set to provide DHCP address on your network, so its router capabilities could be turned on.

if this is true, you may need to rework the connection settings.

here's a recommendation:

1.set your modem to bridge mode (bridge only)
2.this will then be allowing your linksys to manage your DSL connection through PPPoE
3.after so, your linksys router should get a public IP address for an internet IP when you go to status tab (not an IP address starting with 192.168.1.xx)

after so, you may reconfigure your port-forwarding.

the reason why you will need to set your modem to "bridged" only is that if it is not, your zyxel's firewall is also turned on, provided that the linksys' firewall is always on. so even if you define which port will be opened on the router, it will still be blocked by the modem's firewall.