Your MAC address is only visible to the very first link in the chain -the one between your computer and the router- and it legitimately needs that, because that's how it tells data from your computer apart from data from other computers connected to it. This is where IP lives, and it doesn't use MAC addresses.* Data still has to be passed between machines that are directly connected to each other, but even if this is done using only protocols that use MAC addresses, it uses the MAC addresses of the two machines that are passing information between them at the moment, not the MAC address that started it all.
HOW TO GET INTERNET EXPLORER ON A MAC HOW TO
The network layer defines how to get a signal across two computers that are NOT directly connected, using computers that ARE directly connected in some way.
There are other link-layer protocols too, but I won't get into them here. PPP, which is often used by modems, is another example of a link-layer protocol, but it does not use MAC addresses. Ethernet is one example, and so is is the 802.11 family of wireless protocols I list these because they use MAC addresses. The link layer defines how to get a signal across two computers that are directly connected in some way. Depending on who you ask, these layers have different numbers, so I'm going to use the names instead. The exact definitions of each part of the stack differ somewhat from person to person, but the two we're concerned about here are fairly well-defined: the link layer and the network layer. The Internet is not just one protocol, but a series of protocols that stack up on top of each other.