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I am in the Hostel and we are provided with Wi-Fi connectivity.The problem is that the IP address that is assigned to my machine works only for 5-6 hours. I want to refresh the IP address so that i can get access to net for 24 hours.
I have tried the commands like

ipconfig/release

and then

ipconfig/renew

but my IP address remains the same.
I even to switch the router on and off and even forget the network on my pc but nothing seems to change my IP address.
How can i force my IP address to refresh and renew??

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marked as duplicate by Ƭᴇcʜιᴇ007, Heptite, Kevin Panko, ϺОŞΣŞ, random Apr 11 at 19:33

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1 Answer 1

When you use ipconfig /renew, the OS requests an IP address using DHCP; it doesn't just pick a random address, but only the one that the DHCP server offers. In your case, the server is just configured to always offer the same IP address for the same computer – usually based on the computer's MAC address (sometimes the hostname or the DHCP client ID).

You could try changing the network card's MAC address, so that your computer will be recognized as a completely new device.

(Disabling DHCP and configuring the address and routes manually is unlikely to work – as the time restrictions themselves can possibly be MAC address-based – and it can certainly annoy network admins and/or whoever happens to legitimately get the address that you configured.)

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How can i change my network card's MAC address?? –  codefreak Apr 8 at 16:11
1  
@Moses: It is not very nice to post LMGTFY links on a website dedicated to answering questions. –  grawity Apr 8 at 16:55
    
You cannot change your mac adress, because a mac adress is a hardcoded adress for a network device. Some routers can be configured to enter a unique mac adress or copy from a host computer. Another way is simply use different hardware to make that connection. A 2nd wifi adapter in your laptop or simply a different device, such as smartphone would do the trick. –  LPChip Apr 8 at 17:28
    
@codefreak: For what kind of device? Ethernet? WiFi? –  grawity Apr 8 at 17:30
2  
@LPChip: You cannot change the on-chip one, but you can very easily generate packets with whatever address you want. Indeed, that's what pretty much every OS does (the Ethernet header is produced by the OS – sometimes you even have a choice of Ethernet II vs 802.2), and it's how Ethernet bridging works on PCs, for example. (Exceptions exist, such as Bluetooth, which actually relies on the MAC addresses for security purposes.) –  grawity Apr 8 at 17:32

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