On Mar 8, 2011, at 8:32 59AM, Valdis.Kletnieks@vt.edu wrote:
On Tue, 08 Mar 2011 07:37:27 EST, Steven Bellovin said:
No. It was rejected because routers tended to melt down into quivering puddles of silicon from seeing many packets with IP options set -- a fast trip to the slow path. It also requires just as many changes to applications and DNS content, and about as large an addressing plan change as v6. There were more reasons, but they escape me at the moment.
Steve, you of all people should remember the other big reason why:
pathalias tended to do Very Bad Things like violating the Principle of Least Surprise if there were two distinct nodes both called 'turtlevax' or whatever. That, and if you think BGP convergence sucks, imagine trying to run pathalias for a net the size of the current Internet. :)
It wouldn't -- couldn't -- work that way. Leaving out longer paths (for many, many reasons) and sticking to 64-bit addresses, every host would have a 64-bit address: a gateway and a local address. For multihoming, there might be two or more such pairs. (Note that this isn't true loc/id split, since the low-order 32 bits aren't unique.) There's no pathalias problem at all, since we don't try to have a unique turtlevax section. --Steve Bellovin, http://www.cs.columbia.edu/~smb