NETGEAR is aware of a growing number of phone and online scams. To learn how to stay safe click here.
Forum Discussion
Solved
Better explanation of why MAC spoofing works when not able to access some websites?
I have seen several threads here that discuss being unable to access one or two websites. When connected directly to the modem, however, the OP can access those websites. I had the same problem. After trying several different approaches, the one that worked was MAC spoofing/cloning as described here.
The KB article says to use this when unable to connect at all on one or more devices. This was not my problem or the problem in any of the other threads.
There is another thread suggesting that the website itself might be blocking the router's public IP address, so changing the MAC would get around the block. Looks like just about any MAC would work.
And what about this thread that solved essentially the same problem by changing the MTU size?
So, what I want to know is: Why does changing the MAC address seem to work? Is the IP address blocking explanation correct? What about the MTU solution?
Thanks!
For reference: Another thread about the same problem that was solved by MAC spoofing.
MAC spoofing can be used to solve a couple of unrelated problems:
- The ISP has locked onto a specific MAC address and will only provide service to a device with that address. MAC spoofing fakes out the ISP into thinking the router is that permitted device. Note: In some cases, rebooting the modem can force the ISP to lock onto a new MAC address, avoiding the need for MAC spoofing.
- A website has blocked a specific IP address, probably due to abuse by the previous owner of the address. Many ISP's assign an IP address based on the MAC address of the device plugged into the modem. MAC spoofing changes the MAC address and will result in getting a new IP address which is likely not blocked.
Changing the MTU (Maximum Transmission Unit) solves a different problem. The MTU is the size of the largest packet permissible on a link. All devices connected to a link must be set to the same MTU. Otherwise, a device that sends a packet who size exceeds the MTU of another device may see the packet dropped. This could conceivably result in some websites being unreachable; traffic exchanged with those websites exceeds the MTU of the Internet link and are dropped.
1 Reply
MAC spoofing can be used to solve a couple of unrelated problems:
- The ISP has locked onto a specific MAC address and will only provide service to a device with that address. MAC spoofing fakes out the ISP into thinking the router is that permitted device. Note: In some cases, rebooting the modem can force the ISP to lock onto a new MAC address, avoiding the need for MAC spoofing.
- A website has blocked a specific IP address, probably due to abuse by the previous owner of the address. Many ISP's assign an IP address based on the MAC address of the device plugged into the modem. MAC spoofing changes the MAC address and will result in getting a new IP address which is likely not blocked.
Changing the MTU (Maximum Transmission Unit) solves a different problem. The MTU is the size of the largest packet permissible on a link. All devices connected to a link must be set to the same MTU. Otherwise, a device that sends a packet who size exceeds the MTU of another device may see the packet dropped. This could conceivably result in some websites being unreachable; traffic exchanged with those websites exceeds the MTU of the Internet link and are dropped.