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View Full Version : Do IP addresses map to MAC addresses?


RustMan
18-03-2006, 22:06
Is the IP address assigned by NTL's DCHP servers linked to the MAC address?

For years my addy has started 213.nnn but recently this shifted to 83.nnn, but when I switch the router for a laptop and re-provision I get back to 213.nnn. This was also faster (I was doing this to try and resolve a speed issue). Go back to the router and it renewed the lease onto 83. with pi**poor connection until I spoofed the MAC to that of the laptop, rebooted and, hey presto, locked onto 213. and a decent(ish) connection.

Spent days with tech support claiming there (1) my return power was poor, (2) nothing wrong with NTL's side of the link and (3) lots of reasons for poor connection, usually user side and 'you'd be surprised at what can slow it down, oh you're using a router these are notorious etc etc' . (They also offered me a free 1 month trial at 10 Mb .. do Samsung STB's support this?)

Any thoughts on the IP assignment would be appreciated.

Cheers,

Pete

Graham M
18-03-2006, 22:30
Yes, IP Addresses are assigned based on MAC Address.

TheBlueRaja
18-03-2006, 23:09
Yes, IP Addresses are assigned based on MAC Address.

Well, not quite, an IP address is assigned to you by a DHCP server which notes your MAC address and gives you the same address the next time you login.

So for the most part it is the same IP address you get every time.

However the DHCP server has a timeout - so that if for example you leave NTL etc all the IP addresses arent taken up.

So if you didnt use your PC for a while (and i dont know how long this is with NTL) you could log in and get a different IP address as the timeout would have expired.

Either way your IP address and MAC address is logged.

RustMan
19-03-2006, 00:33
In this case the I'd been connecting via the same MAC (spoofed to the router) for around 4 years through 2 STBs. NTL had assigned a completely different IP address on a different gateway in the past few weeks, but then revert to one on the original gateway when I connect a new MAC they'd not seen before.

Just happens to give a better performance.

ResponseTek's helpful response to the problems was:

Please accept my apologies for the problems you are experiencing with your broadband connection.

I have looked into your situation in more depth and I can see that there are some network issues in your area. These would cause the problems that you have been facing, (dropped connections, slow browsing and downloads). At the moment there is no work scheduled to resolve this issue.

ntl is committed to provide all it's customers with the highest quality service possible. I am sorry that I cannot provide you with more information on when any work to upgrade the network will be carried out.


At least its more honest than the call centre brush offs.

Pete

Chrysalis
19-03-2006, 10:38
Is the IP address assigned by NTL's DCHP servers linked to the MAC address?

For years my addy has started 213.nnn but recently this shifted to 83.nnn, but when I switch the router for a laptop and re-provision I get back to 213.nnn. This was also faster (I was doing this to try and resolve a speed issue). Go back to the router and it renewed the lease onto 83. with pi**poor connection until I spoofed the MAC to that of the laptop, rebooted and, hey presto, locked onto 213. and a decent(ish) connection.

Spent days with tech support claiming there (1) my return power was poor, (2) nothing wrong with NTL's side of the link and (3) lots of reasons for poor connection, usually user side and 'you'd be surprised at what can slow it down, oh you're using a router these are notorious etc etc' . (They also offered me a free 1 month trial at 10 Mb .. do Samsung STB's support this?)

Any thoughts on the IP assignment would be appreciated.

Cheers,

Pete

Now thats interesting, the only explanation I could give regarding the 213 ip speed increase is ntl's static routing providing better routes for that ip range.