MAMEWorld Forums - The Loony Bin

> First, I don't know what DHCP is except it's needed for assigning IPs, but I don't
> know how, or why, or even if I need it.
>
> I've always noticed that everytime I reboot my router, my internal IP changes.
> Sometimes it's 192.168.1.128, sometimes 129 and sometimes 130. It changes apparently
> randomly between those values.
>
> On the other hand, my blu-ray player is also connected to the router, and as far as I
> know it always takes 131, although I rarely watch its config unless it stops working
> (but more often than not, it's an issue with Serviio).
>
> Today I had a problem connecting with some parts of the interwebs internets and after
> fixing it I was just lazily moving through the router configuration, and saw that I
> had DHCP enabled, and it was configured to assign IPs in the range of 128 to 160. It
> also says that the leased time is 72 hours, and hell if I really understand what that
> means other than EnableDelayedDHCPRefreshHappiness == linearalgebra(72).
>
> Is that somehow connected to my computer having a different IP each time the router
> reboots? Should I disable DHCP or leave it enabled? Is there a way to make my
> computer always get 192.168.1.128?
>
> Thanks in advance for any insight. Take a beer, help yourself some crackers. Use my
> wife.

DHCP stands for "Dynamic Host Configuration Protocol." This service just gives any device connected to your router its own IP address from an IP address range already set on the router. This address range is changeable if desired.

Lease Time is exactly what it sounds like.

Every 3 days, or 72 hours, your router gives your internet-connected devices a new IP from the IP range that was set, which in your case, was 192.168.1.128 - 192.168.1.160.

Before doing the steps below for giving yourself a static IP address, go to the Start Menu, type cmd in the search programs and menus field, and press enter.

Once the commandline appears, type ipconfig and write down the default gateway number that appears.

To give yourself a statically assigned IP address (in Windows 7), you must:

1) Go to Control Panel and select View Network Status and Tasks.

2) Once there, on the left hand side of the window, select Change Adapter Settings

3) Select "Local Area Connection," or, if using wireless, "Wireless Network Connection," and right-click on the icon.

4) In the drop-down menu that follows, select "Properties."

5) In the networking tab, select Internet Protocol v4 and press Properties.

6) Where it says, "Use the following IP address," select the button and type the following:

IP Address: 192.168.1.128
Subnet Mask: 255.255.255.0
Default Gateway: 192.168.1.1

However, because that .128 address is in your DHCP range, you run the risk of an IP address collision (meaning two devices on your network with the same IP address). As a result, it's recommended to give yourself an IP outside of that range. For example: 192.168.1.127

Also, instead of doing the above, you can also tell the router to automatically assign specific IP addresses to certain devices. This is known as a "DHCP Address Reservation." It's also a much better idea to do this than manually assign IPs to each and every device on your network.

Most home routers have a page that allows you to do DHCP Address Reservations. If you do that, your IP addresss will not change for the devices that you do this to.