[X4U] MAC address vs ? Ethernet Address ?

[Doug LaBore]

> Could you explain this a little more? I'm not that well versed in computer
> terminology. 
> 
> What's a contiguous layer 2 network?

Network computers have a standard way they all communicate over a Ethernet
network its called the "Open System Interconnection" or OSI model and it
consists of 7 layers each handling one aspect of the communications.

The 1st layer is the physical layer that's the actual cable & hardware used
to interconnect two computers or networks.

The 2nd layer is the "Data Link" layer. This is where each network device
watches all the bits on the wire and decides what to use and what to throw
away if that packet isn't for your computer. This is the layer that utilizes
the MAC address (media access control). All devices on your local LAN
network actually communicate at this layer and only need to move to layer 3
if they need to communicate with a device out on the internet or on another
subnet elsewhere on your LAN.

Layer 3 is called the "Network" layer and utilizes IP numbers to route
packets to the right computer or to a network that knows how to communicate
with your computer.

There are four more layers 4-Transport, 5-Session, 6-Presentation,
7-Application. That make higher level decisions as to what to do with each
packet that the lower layers pass through, but we can talk about those
another time.

Hope my humble description helps...

Doug LaBore