From Slashdot: Comcast goes after NAT users-MAC Addr

[Jeremy Fowler]

> Jeremy,
> 
> Re, ". . . the MAC address IS the address of the originating device. . . .":
> 
> 1)  What does the acronym MAC stand for? (just curious, not important to me)

Medium Access Control
 
> 2) What is the originating device?  The Syslink 4 port router (firewall)
> that my 2 or 3 computers are tied into, which then goes out the DSL modem?

The device that originally sent the packet out onto the network. 
(One of your 2 or 3 computers)