µTasker Forum

µTasker Forum => µTasker general => Topic started by: svl on October 20, 2010, 12:38:08 PM

Title: Getting the MAC address from the connecting client to a TCP server
Post by: svl on October 20, 2010, 12:38:08 PM

Hi Mark

Is it possible to somehow get the MAC address of the client that are trying to connect to a TCP server I uTasker?
I can see that the white list supports IP addresses, but some of our customer want it to be the MAC address that are used as white list.
I was thinking of using the ARP table, but am unsure if the ARP table always has it in its table or it need to make a lookup.
If it need to make a lookup that I am afraid that the uTasker system will get lock in circles while the ARP service are fetching the MAC address…

Regards

Steen

Title: Re: Getting the MAC address from the connecting client to a TCP server
Post by: mark on October 20, 2010, 02:22:50 PM

Hi Steen

I think that you can use an ARP look-up to get the MAC address - I don't think that this will cause any problems. If a TCP frame has just been received its IP/MAC combination will certainly be in the cache.

However note that there are only different MAC addresses when the clients are on the local network. Any traffic arriving from an external connection will have the MAC address of the router.  Therefore I suppose that they want to define limited PCs on the local network to have access (?)

Regards

Mark

Title: Re: Getting the MAC address from the connecting client to a TCP server
Post by: svl on October 21, 2010, 06:41:48 AM

Hi Mark

Thanks for the reply.
You are completely right. Our systems will normally only be accessible to unit on the local net.
The idée of using the MAC address are that it is harder for a 3. person to duplicate this kind of communication.   
I will give it a try

Regards
 
Steen