Again, you're mixing things here. A subnet is a way of organizing IP addresses, which has nothing todo with ethernet and MAC addresses except for the fact that you can do IP over Ethernet...much like you can do IP over carrier pigeons ;-)
Le 3 Janvier 2003 14:56, vous avez �crit : > His question seemed to be looking for an overview rather than meat and > potatoes. > > Others answered in a similar (though less long-winded way). My PC's Mac > doesn't matter except in my own subnet. Changing the MAC won't matter > unless it's a duplicate on your own subnet. > > Kev. > > > ----- Original Message ----- > From: "S�bastien Taylor" <[EMAIL PROTECTED]> > To: <[EMAIL PROTECTED]> > Sent: Friday, January 03, 2003 2:37 PM > Subject: Re: (clug-talk) MAC s > > > Actually no, that's not how it works. When sending ethernet data you use > MAC > to address devices, when sending TCP/IP data you use IP addresses. Since > on an ethernet network TCP/IP is sent over ethernet, TCP/IP packets are > encapsulated in ethernet frames. You can have different physical network > types on the same TCP/IP subnet which can talk to each other using IP > addresses...obviously the same cannot be said about MAC addresses, since > the next network might not be ethernet based. I would recommend reading up > on the ISO/OSI Network Model. > > Here's some hits... > > http://www.google.ca/search?hl=fr&ie=UTF-8&oe=UTF-8&q=OSI+Network+Model&met >a = > > Le 3 Janvier 2003 13:45, vous avez �crit : > > An IP address is used to uniquely locate a NIC on a different subnet. A > > MAC is used to uniquely locate a NIC on the same Subnet. > > > > So the IP address is used to hop across routers until it reaches the > > network the destination is a member of (192.168.0.0/24 for example). The > > router will then pass the packet to the MAC (NOT THE IP) address of the > > recipient. > > > > MACs are therefore necessary to allow communication on a network. I > > can't think of a disadvantage. Potentially it could have some privacy > > implications, because they obviously uniquely identify a PC, but this > > isn't > > > really much of a concern, MACs aren't passed across routers. Once a > > packet > > > leaves a given network, it uses an IP address until it reaches it's > > destination. > > > > Being able to change your MAC address is a mixed blessing. If you change > > your MAC to be the same as someone else's on your subnet, that can be > > really fun. Particularly if the troubleshooter isn't experienced. Old > > Card (Especially ARCnet (in my experience)) sometimes had duplicate MACs. > > Being able to change you MAC is part of the TCP/IP spec. > > > > Kev. > > > > > > > > > > ----- Original Message ----- > > From: "BentWig Nut" <[EMAIL PROTECTED]> > > To: <[EMAIL PROTECTED]> > > Sent: Wednesday, January 01, 2003 3:58 PM > > Subject: (clug-talk) MAC s > > > > > Hello all. > > > > > > Q1: What are the pros and cons of a M.A.C. address? > > > > > > Q2: What are the advantages and disadvantages of being able to > > > > > > change the MAC ? > > > > > > Waiting for the roof to fall in... > > > > > > > > > > > > > > > > > > _________________________________________________________________ > > > MSN 8: advanced junk mail protection and 2 months FREE*. > > > http://join.msn.com/?page=features/junkmail
