How data transfer is monitored?
 

Can anyone please explain me how bandwith or data transfer is monitored by ISP. Do they monitor some ports TCP IP port 21,80 etc or they use the MAC address of the ethernet card to monitor and calculate the data transfer.
Is UDP, TCP , ICMP used by the ISP to monitor the transfer.
For eg. I use cable internet. My ISP takes my MAC address then only I can do the browsing. So anytime I have to change the MAC address I have to inform the ISP to register it with his system.
But why I have to register the MAC address with ISP. Is my ISP using MAC address to monitor the transfer.
Thanks.

I would imagine that you need to register your MAC address with their DHCP server so that you get an IP address. They would then use this IP address if they wanted to monitor traffic.

HTH

Jamie..

It's not DHCP but static IP.

So you tell your system your IP address instead of always getting the same address from their DHCP server (hence its static but still uses DHCP)? That pretty unusual. If this is the case I'm not sure why they would need your MAC address, it wouldn't be useful for monitoring as its only seen on your segment of the network, as soon as it goes off your subnet (through a router) your MAC address is removed and the MAC of the router takes it place.

cheers

Jamie...