can't connect my Android device to the router dwr 712 how can i make my Android IP address static so that I can enable my phone to connect to my router when I enable WI FI MAC address filter
If you're talking about your own WiFi network, a network address must be agreed upon by your router and your Android device. This is usually done via DHCP, with your router managing available IP addresses and assigning them to devices which connect to it.

Now, those addresses are usually assigned dynamically, and „time out“ when the „lease time“ configured in the router is running out and the device has not been connected within that time frame. That's done so the router doesn't run out of available IP addresses, which are (in a class C network, which is commonly used here) limited to 254.

So if you want your Android device always to use the same IP address, there are two approaches you can take – depending on what your router supports:


tell the router to „always assign the same IP to that device“
use an IP address outside the configured DHCP range and configure that as „fixed IP“ with your Android device.


The former is easier to achieve, and there's nothing you'd need to configure on the Android device for that.

For the second approach, you first need to check with your router about the DHCP range (wich might e.g. be 192.168.0.200 and higher), then pick an address outside that range but still in the same network and not already used by another device, e.g. 192.168.0.199 with the mentioned example (don't use .0 or .255, which are reserved for special use). Then configure that in your Android device, by editing the settings of your WiFi network:


Go to Settings › WiFi (where the networks are listed)
long tap the entry of your WiFi, and chose to „edit“ its settings
chose to show „advanced“ options
enter the IP address (from above calculation), gateway IP (your router's IP), name server (e.g. consult your router what it uses, or try with the router's IP again), and the network mask (with a class C network, that would be 255.255.255.0)
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