Overhead shmoverhead. Seriously, we're fighting over the non-issue. It's not the "wasted" 0.02% of bandwidth (@ 1Gbps) that's the issue. It's the utility of a "come as you are" "plug and play" network that "Ethernet" (which really loosely means all IEEE 802 protocols) provides, which the current carrier networks do not. If I read the thread correctly, what you really are asking for is the ability to plug your IEEE compliant gig/10gig switch into a carrier port and just have it ARP and respond for valid IP addresses on the segment, as opposed to all the back and forth provisioning, truck rolls, and interaction with bell-head union workers that the current system requires. Now, HOW to accomplish that is an interesting discussion, and the first valid result will probably be a great business. That doesn't require breaking Ethernet, using promiscuous mode, or much except the carriers stopping trying to throw their legacy circuit-switched requirements onto a packet switched network. There's plenty of fiber in the ground. Light dark stuff with the new network, plug it into IEEE 802* compliant layer 2, and IETF compliant layer 3 infrastructure; and leave the dying Bellcore/ITU network on the old copper and SONET.
-----Original Message----- From: sthaug@nethelp.no [mailto:sthaug@nethelp.no] Sent: Wednesday, July 08, 2009 11:34 PM To: tkapela@gmail.com Cc: nanog@nanog.org Subject: Re: Point to Point Ethernet
Best case, you blow 12 bytes on IFG in gig, 20 bytes on fast-e/slow-e.
As far as I know Gig and 10 Gig (with LAN PHY) are exactly the same as 10 and 100 Mbps in this respect, i.e. 8 bytes of preamble and 12 bytes of IFG. So you always have an overhead of 20 bytes, no matter what.
10 Gig with WAN PHY is a whole different ballgame, of course.
Steinar Haug, Nethelp consulting, sthaug@nethelp.no