[Android Central Question]

I keep getting told my ip on my phone should change all the time but it doesn't
Anyways if I get a brand new phone and put my old SIM in will I get a new ip. Is it from the phone or the sim you get your ip address.

Thanks

[SpookDroid]

Unless you have configured your network settings to have a static IP, yes, EVERY time you connect to a network you should be getting a new IP. The IP is assigned by the network to the phone's modem (be it mobile or Wi-Fi). Each device, however, comes with a unique identifier (IMEI) that mobile networks use to identify your specific phone and cannot be changed.

[ManiacJoe]

When you connect your device to a network -- cellular or public wifi -- your phone is assigned an IP address by the network, usually on a first-available sequence as the IP addresses get recycled as phones come and go on the network.

For home wifi systems, the process is similar. However, since your home wifi has very few devices attached to it, the system will often remember your device and give it the same IP address as it had before because there are not enough devices to cause a recycling of the IP addresses available (usually 255).

Many of the wifi routers will also let you turn off the auto assign feature where you can then explicitly assign IP addresses to each device.

One thing to note is that there are internal and external IP addresses. External IP addresses are associated with the router's connection to the internet. They are assigned by the ISP. Every device connected to that router gets the same external IP address. Internal IP addresses are local to the network, and usually start with a "10." or "192."

[Rukbat]

For home wifi systems, the process is similar. However, since your home wifi has very few devices attached to it, the system will often remember your device and give it the same IP address as it had before because there are not enough devices to cause a recycling of the IP addresses available (usually 255).

252 - 1 is normally the router, and 0 and 255 are reserved. 0 for the network address and 255 for broadcast.

Internal IP addresses are local to the network, and usually start with a "10." or "192."

10.0.0.1 to 10.255.255.254
172.16.0.1 to 172.31.255.254
192.168.0.1 to 192.168.255.254